Despite centuries of taboo and titillation, masturbation in primates appears to serve an evolutionary purpose. A study published June 6 in the journal Proceedings of The Royal Society B, found that self-stimulating increases reproductive success and helps primates avoid sexually transmitted infections (STI), at least in males. 

[Related from PopSci+: These sex toys are designed to heal, one orgasm at a time.]

Self-pleasure is common across the animal kingdom, but is particularly frequent in primates including humans. The behavior was considered by some scientists to be either pathological or simply a by-product of sexual arousal. Recorded observations were also too fragmented to fully understand masturbation’s distribution, evolutionary history, or adaptive significance. 

In this new study, a team of researchers built a dataset on primate masturbation from close to 400 sources, including 246 published academic papers, and 150 questionnaires and personal communications from zookeepers and primatologists. To understand why and when the practice evolved in both females and males, the authors tracked the distribution of autosexual behavior across primates.

They found that masturbation has a long evolutionary history amongst primates, and was likely present in the common ancestry of all monkeys and apes, humans included. What was less clear is whether the common ancestor of other primates—lemurs, lorises and tarsiers—masturbated, largely because there was less data on these groups.

The team tested multiple hypotheses to better understand why this seemingly non-functional trait would evolve. According to the postcopulatory selection hypothesis, masturbation aids successful fertilization that can be achieved in various ways. 

Masturbation without ejaculation can increase arousal before sexual intercourse, which may be a useful tactic for low-ranking primate males that are likely to be interrupted during sex. 

Masturbation with ejaculation allows males to shed their more inferior semen, which leaves the fresh, high-quality semen available for mating. This super semen may be more likely to outcompete the semen of other males, which is necessary in primate communities with steep competition for mates. The study found support for this second hypothesis, namely that male masturbation co-evolved within multi-male mating systems where competition between males is high.

[Related: Scientists think they found a 2,000-year-old dildo in ancient Roman ruins.]

According to the pathogen avoidance hypothesis, male masturbation reduces the chance of contracting an STI by cleansing the urethra with ejaculate. The team also found evidence to support this hypothesis, with the data revealing that masturbation in males co-evolved with high STI load across the primate tree of life.

The significance of female masturbation remains less clear. While it is frequent, fewer studies and reports describe female self-pleasure.The team argues that more data on female sexual behavior is needed before understanding masturbation’s evolutionary role in females. 

“Our findings help shed light on a very common, but little understood, sexual behavior and represent a significant advance in our understanding of the functions of masturbation,” study co-author and University College London anthropologist Matilda Brindle said in a statement. “The fact that autosexual behavior may serve an adaptive function, is ubiquitous throughout the primate order, and is practiced by captive and wild-living members of both sexes, demonstrates that masturbation is part of a repertoire of healthy sexual behaviors.”

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The International Space Station received roughly 7,000 pounds of supplies and scientific experiment materials early Tuesday morning following the successful autonomous docking of a SpaceX Dragon cargo spacecraft. According to NASA, the Dragon will remain attached to the ISS for about three weeks before returning back to Earth with research and cargo. In addition to a pair of International Space Station Roll Out Solar Arrays (IROSAs) designed to expand the microgravity complex’s energy-production ability, ISS crew members are receiving materials for a host of new and ongoing experiments.

[Related: Microgravity tomatoes, yogurt bacteria, and plastic eating microbes are headed to the ISS.]

THOR, an aptly named investigation courtesy of the European Space Agency, will observe Earth’s thunderstorms from above the atmosphere to examine and document electrical activity. Researchers plan to specifically analyze the “inception, frequency, and altitude of recently discovered blue discharges,” i.e. lightning occurring within the upper atmosphere. Scientists still know very little about such phenomena’s effects on the planet’s climate and weather, but the upcoming observations could potentially shed more light on the processes.

Meanwhile, researchers are hoping to stretch out telomeres in microgravity via Genes in Space-10, part of an ongoing national contest for students in grades 7 through 12 to develop their own biotech experiments. These genetic structures protect humans’ chromosomes, but generally shorten over time as they age. Observing telomere lengthening in ISS microgravity will give scientists a chance to determine if their size change relates to stem cell proliferation. Results could help NASA and other researchers better understand effects on astronauts’ health during long-term missions, a particularly topical subject given their hopes for upcoming excursions to the moon and Mars.

ISS will also deploy the Educational Space Science and Engineering CubeSat Experiment (ESSENCE), a tiny satellite housing a wide-angle camera capable of monitoring ice and permafrost thawing within the Canadian Arctic. This satellite comes alongside another student collaboration project called Iris, which is meant to observe geological samples’ weathering upon exposure to direct solar and background cosmic radiation.

[Related: The ISS’s latest arrivals: a 3D printer, seeds, and ovarian cow cells.]

Finally, a set of plants that germinated from seeds first produced in space and subsequently traveled to Earth are returning to the ISS as part of Plant Habitat-03. According to NASA, plantlife often adapts to the environmental stresses imposed on them via spaceflight, but it’s still unclear if these changes are genetically passed on to future generations. PH-03 will hopefully help scientists better understand these issues, which could prove critical to food generation during future space missions and exploration efforts.

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Earth is facing a biodiversity crisis, with species extinction accelerating at a startling pace. Policy action is finally catching up with the dilemma, as the United Nations reached a historic deal to protect 30 percent of the Earth’s wilderness by 2030 in December 2022. Addressing this crisis will face an uphill battle– including the infrastructure needed to quantify these losses.

[Related: Why you can’t put a price on biodiversity.]

This crucial data may now come from a surprising source: air quality monitoring stations. In a study published June 5 in the journal Current Biology finds that for decades, thousands of these ambient air quality monitoring stations all over the world have inadvertently been collecting environmental DNA (eDNA) in their filters.

“One of the biggest challenges in biodiversity is monitoring at landscape scales—and our data suggest this could be addressed using the already existing networks of air quality monitoring stations, which are regulated by many public and private operators,” study co-author and York University ecologist Elizabeth Clare said in a statement. “These networks have existed for decades, but we have not really considered the ecological value of the samples they collect.”

Air quality monitoring stations have been around for decades, but methods of capturing and analyzing eDNA are relatively new. Data from previous studies offered proof-of-concept evidence that it was possible to identify the species in a zoo by sampling the air.

In this new study, a team of researchers tested whether airborne eDNA that holds information on local plant, insect, and other animal life is captured on these filters as a by-product of the normal operations of air quality monitoring networks. These networks  typically monitor for heavy metals and other pollutants. 

They extracted and amplified DNA from the filters at two locations in the United Kingdom and recovered eDNA from over 180 different fungi, plants, insects, mammals, birds, amphibians, and other animal groups. The species list included many charismatic species, including badgers, dormice, little owls, and smooth newts. Additionally, they were able to pick up DNA from species of special conservation interest such as hedgehogs and songbirds. Trees and plants included ash, linden, pine, willow, oak, yarrows, mallows, daisy, nettles, and grasses. DNA from arable crops such as wheat, soybean, and cabbage was also identified, according to the study.

Additionally, the filters contained DNA from 34 species of birds. Data showed that longer sampling times captured a larger number of vertebrate species, possibly as more birds and mammals visited the area over time. 

[Related: We don’t have a full picture of the planet’s shrinking biodiversity. Here’s why.]

According to the team, air quality monitoring networks have been gathering local biodiversity data in a very standardized way, but the ecological significance has long gone unnoticed. Samples are kept for decades in some places, which suggests that existing samples that capture ecological data over time may already exist. With only some minor changes, these samples could be used for detailed monitoring of land-based biodiversity using a network already in full operation.

“The most important finding, to my mind, is the demonstration that aerosol samplers typically used in national networks for ambient air quality monitoring can also collect eDNA,” James Allerton, a co-author and an air quality specialist from the UK’s National Physical Laboratory. said in a statement. “One can infer that such networks—for all their years of operation and in other countries around the world—must have been inadvertently picking up eDNA from the very air we breathe.”

The team is currently working to preserve as many of these samples as they can with eDNA in mind. The team says it will take a global effort to reach all of their trove of biodiversity data. 

“The potential of this cannot be overstated,” study co-author and Queen Mary University of London biologist Joanne Littlefair said in a statement. “It could be an absolute game changer for tracking and monitoring biodiversity. Almost every country has some kind of air pollution monitoring system or network, either government owned or private, and in many cases both. This could solve a global problem of how to measure biodiversity at a massive scale.”

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This article is republished from The Conversation.

Brazil’s coastal waters teem with a rich array of species that paint a living tapestry beneath the waves. This underwater world is particularly special because many of its species are endemic – they are found nowhere else on Earth. The southwestern Atlantic is home to 111 endemic reef fish species, each of which plays a crucial role in the intricate web of marine life.

An uninvited guest has arrived in these tropical waters: the Pacific red lionfish (Pterois volitans). Renowned for its stunning appearance and voracious appetite, the lionfish was first detected off of Florida in 1985 and has spread throughout the Caribbean, killing reef fish in large numbers.

Now it has breached a formidable obstacle: the Amazon-Orinoco river plume, which flows into the Atlantic from northeastern Brazil. This massive discharge of fresh water has long functioned as a barrier separating Caribbean fish species from those farther south along Brazil’s coastline.

Scientists and environmental managers widely agree that the lionfish invasion in Brazil is a potential ecological disaster. As a marine ecologist, I believe mitigating the damage will require a comprehensive approach that addresses the ecological, social and economic harms wrought by this predatory fish.

Tracing the lionfish’s spread

It’s easy to see why lionfish appeal to aquarium enthusiasts. Native to the warm waters of the Indo-Pacific ocean, they are 12 to 15 inches long, with red and white stripes and long, showy fins. They protect themselves with dorsal spines that deliver painful venomous stings.

Lionfish were first detected in the Atlantic Ocean in 1985 off Dania Beach, Florida, probably discarded by a tropical fish collector. Since then they have spread throughout the Caribbean Sea, the Gulf of Mexico and northward as far as Bermuda and North Carolina – one of the most successful marine invasions on record. A close relative, the common lionfish or devil firefish (Pterois miles), has invaded the Mediterranean Sea and is spreading rapidly there.

Lionfish can be eaten safely if they are properly prepared to remove their venomous spines. In Florida and the Caribbean, lionfish hunting tournaments have become popular as a control method. However, lionfish move to deeper waters as they grow, so hunting alone can’t prevent them from spreading.

Marine scientists have anticipated for years that lionfish would someday arrive along the eastern coast of South America. A single sighting in 2014, far removed from the Amazon-Orinoco plume, was likely a result of an aquarium release rather than a natural migration.

Then in December 2020, local fishermen caught a pair of lionfish on coral reefs in the mesophotic, or “twilight,” zone several hundred feet below the mighty Amazon River plume. A scuba diver also encountered a lionfish in the oceanic archipelago of Fernando de Noronha, 220 miles (350 kilometers) off Brazil’s tropical coast.

New invasion fronts have quickly opened along Brazil’s north and northeast coasts, covering eight states and diverse marine habitats. More than 350 lionfish have been tallied along a 1,720-mile (2,765-kilometer) swath of coastline.

Aggressive predators without natural enemies

Like many introduced species, lionfish in the Atlantic don’t face natural population control mechanisms such as predation, disease and parasitism that limit their numbers in the Indo-Pacific. A 2011 study found that lionfish on reefs in the Bahamas were larger and more abundant than their Pacific counterparts.

Lionfish thrive in many marine habitats, from mangroves and seagrass beds to deepwater reefs and shipwrecks. They are aggressive, persistent hunters that feed on smaller fish, including species that keep coral reefs clean and others that are food for important commercial species like snappers and groupers. In a 2008 study, when lionfish appeared on reefs in the Bahamas, populations of small juvenile reef fish declined by 80% within five weeks.

Brazil’s northeast coast, with its rich artisanal fishing activity, stands on the front line of this invasive threat. Lionfish are present in coastal mangrove forests and estuaries – brackish water bodies where rivers meet the sea. These areas serve as nurseries for important commercial fish species. Losing them would increase the risk of hunger in a region that is already grappling with substantial social inequality.

Fishers also face the threat of lionfish stings, which are not lethal to humans but can cause painful wounds that may require medical treatment.

Facing the invasion: Brazil’s challenges

Biological invasions are easiest to control in early stages, when the invader population is still growing slowly. However, Brazil has been slow to react to the lionfish incursion.

The equatorial southwestern Atlantic, where the invasion is taking place, has been less thoroughly surveyed than the Caribbean. There has been little high-resolution seabed mapping, which would help scientists identifying potential lionfish habitats and anticipate where lionfish might spread next or concentrate their populations. Understanding of the scale of the invasion is largely based on estimates, which likely underrepresent its true extent.

Moreover, turbid waters along much of Brazil’s coast make it hard for scientists to monitor and document the invasion. Despite their distinctive appearance, lionfish are difficult to spot and record in murky water, which makes it challenging for scientists, divers and fishers to keep an accurate record of their spread.

Still another factor is that from 2018 through 2022, under former President Jair Bolsonaro, Brazil’s government sharply cut the national science budget, reducing funding for field surveys. The COVID-19 pandemic further reduced field research because of lockdowns and social distancing measures.

Making up for lost time

Brazil has a history of inadequately monitoring for early detection of marine invasions. The lionfish is no exception. Actions thus far have been reactive and often initiated too late to be fully effective.

As one of many Brazilian scientists who warned repeatedly about a potential lionfish invasion over the past decade, I’m disheartened that my country missed the window to take early action. Now, however, marine researchers and local communities are stepping up.

Given the length of Brazil’s coast, traditional monitoring methods are often insufficient. So we’ve turned to citizen science and information technology to fill the gaps in our knowledge.

In April 2022, a group of academic researchers spearheaded the launch of an online dashboard, which is updated continuously with data from scientific surveys and local community self-reports. This interactive platform is maintained by a research group led by marine scientists Marcelo Soares and Tommaso Giarrizzo from the Federal University of Ceará.

The dashboard allows anyone, from fishers to recreational divers and tourists, to upload data on lionfish observations. This information supports rapid response efforts, strategic planning for preventive measures in areas still free from lionfish, and the development of localized lionfish removal programs.

I believe lionfish are here to stay and will integrate over time into Brazil’s marine ecosystems, much as they have in the Caribbean. Given this reality, our most pragmatic and effective strategy is to reduce lionfish populations below levels that cause unacceptable ecological harm.

Regions along the coast that are still lionfish-free might benefit from early and preventive actions. Comprehensive surveillance plans should include environmental education programs about exotic species; early detection approaches, using techniques such as analyzing environmental DNA; citizen science initiatives to monitor and report lionfish sightings, participate in organized culls and help collect research data; and genetic surveys to identify patterns of connectivity among lionfish populations along Brazil’s coast and between Brazilian and Caribbean populations.

Brazil missed its initial opportunity to prevent the lionfish invasion, but I believe that with strategic, swift action and international collaboration, it can mitigate the impacts of this invasive species and safeguard its marine ecosystems.

This article has been updated to reflect that the correct number of endemic reef fish species in the southwestern Atlantic is 111.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Bees are not just the only precious pollinators in need of strong conservation and protection efforts. A study published June 5 in the journal Ecology Letters found that not only do night-time pollinators such as moths likely visit just as many plants as bees, but they may be less resilient than bees due to their more complex life cycle and more specific plant requirements.

[Related: Move over, bees: The lowly weevil is a power pollinator.]

The study also found that despite these threats and pressures, moths play a critical role in supporting plant communities in urban settings, accounting for roughly a third of all pollination in trees, crops, and flowering plants. In more urbanized areas, the diversity of pollen that is carried by bees and moths decreases, and the urban pollinators have fewer flower resources available.  

The team behind the study suggests that supporting the introduction of plant species that are beneficial to moths and bees will only be more important to the health of urban ecosystems. 

“As moths and bees both rely on plants for survival, plant populations also rely on insects for pollination,” study co-author and pollinator ecologist at the University of Sheffield Emilie Ellis said in a statement. “Protecting urban green spaces and ensuring they are developed in such a way that moves beyond bee-only conservation but also supports a diverse array of wildlife, will ensure both bee and moth populations remain resilient and our towns and cities remain healthier, greener places.”

According to the study, bees and moths also visit very different plant communities. Moths were found to be carrying more pollen than previously believed, and tend to visit more types of trees and fruit crops, along with their usual pale fragrant flower species. Urbanized areas can sometimes have less diversity in plant species and an overabundance of non-native plant species. These can both lead to lower insect interactions for less attractive plant species, which harms both insect and plant populations. 

The team used DNA sequencing to identify the pollen that sticks to night-flying moths as they visit flowers. This analysis revealed the wide range of plant species that are not likely pollinated by bees.

[Related: The alluring tail of the Luna moth is surprisingly useless for finding a mate.]

“It’s clear from this study that pollination is achieved by complex networks of insects and plants, and these networks may be delicate, and sensitive to urbanization,” co-author and University of Sheffield evolutionary and chemical ecologist Stuart Campbell said in a statement. “We can also learn which plant species might be the best sources of food for different insects, including nocturnal ones like adult moths, and use that information to better provide for all our pollinators”.

Better understanding how crucial moths are to pollinating plants has implications for urban planning, policy, and wildlife-friendly garden initiatives, especially since populations have dropped by about 33 percent in the United Kingdom over the past half century alone.

“When planning green spaces, consideration needs to be given to ensure planting is diverse and moth-friendly as well as bee-friendly, to ensure both our plants and insects remain resilient in the face of the climate crisis and further losses,” said Ellis.

Some advice for making your own garden more pollinator friendly include using plants that attract both specialist pollinators and generalist pollinators, planting a wide variety of plant species, and keeping those weeds growing.

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This article was originally published on Undark.

It could have been a scene from Jurassic Park: ten golden lumps of hardened resin, each encasing insects. But these weren’t from the age of the dinosaurs; these younger resins were formed in eastern Africa within the last few hundreds or thousands of years. Still, they offered a glimpse into a lost past: the dry evergreen forests of coastal Tanzania.

An international team of scientists recently took a close look at the lumps, which had been first collected more than a century ago by resin traders and then housed at the Senckenberg Research Institute and Natural History Museum in Frankfurt, Germany. Many of the insects encased within them were stingless bees, tropical pollinators that can get stuck in the sticky substance while gathering it to construct nests. Three of the species still live in Africa, but two had such a unique combination of features that last year, the scientists reported them to be new to science: Axestotrigona kitingae and Hypotrigona kleineri.

Species discoveries can be joyous occasions, but not in this case. Eastern African forests have nearly disappeared in the past century, and neither bee species has been spotted in surveys conducted in the area since the 1990s, noted coauthor and entomologist Michael Engel, who recently moved from a position at the University of Kansas to the American Museum of Natural History. Given that these social bees are usually abundant, it’s unlikely that the people looking for insects had simply missed them. Sometime in the last 50 to 60 years, Engel suspects, the bees vanished along with their habitat.

“It seems trivial on a planet with millions of species to sit back and go, ‘Okay, well, you documented two stingless bees that were lost,’” Engel said. “But it’s really far more troubling than that,” he added, because scientists increasingly recognize that extinction is “a very common phenomenon.”

The stingless bees are part of an overlooked but growing trend of species that are already deemed extinct by the time they’re discovered. Scientists have identified new species of bats, birds, beetles, fish, frogs, snails, orchids, lichen, marsh plants, and wildflowers by studying old museum specimens, only to find that they are at risk of vanishing or may not exist in the wild anymore. Such discoveries illustrate how little is still known about Earth’s biodiversity and the mounting scale of extinctions. They also hint at the silent extinctions among species that haven’t yet been described — what scientists call dark extinctions.

It’s critical to identify undescribed species and the threats they face, said Martin Cheek, a botanist at the Royal Botanic Gardens, Kew, in the United Kingdom, because if experts and policymakers don’t know an endangered species exists, they can’t take action to preserve it. With no way to count how many undescribed species are going extinct, researchers also risk underestimating the scale of human-caused extinctions — including the loss of ecologically vital species like pollinators. And if species go extinct unnoticed, scientists also miss the chance to capture the complete richness of life on Earth for future generations. “I think we want to have a full assessment of humans’ impact on nature,” said theoretical ecologist Ryan Chisholm of the National University of Singapore. “And to do that, we need to take account of these dark extinctions as well as the extinctions that we know about.”

Many scientists agree that humans have pushed extinctions higher than the natural rate of species turnover, but nobody knows the actual toll. In the tens of millions of years before humans came along, scientists estimate that for every 10,000 species, between 0.1 and 2 went extinct each century. (Even these rates are uncertain because many species didn’t leave behind fossils.) Some studies suggest that extinction rates picked up at least in the past 10,000 years as humans expanded across the globe, hunting large mammals along the way.

Islands were particularly hard hit, for instance in the Pacific, where Polynesian settlers introduced pigs and rats that wiped out native species. Then, starting in the 16th century, contact with European explorers caused additional extinctions in many places by intensifying habitat loss and the introduction of invasive species — issues that often continued in places that became colonies. But again, scientists have a poor record of biodiversity during this time; some species’ extinctions were only recognized much later, most famously the dodo, which had disappeared by 1700 after 200 years of Europeans hunting and then settling on the island in the Indian Ocean island it inhabited.

Key drivers of extinction, such as industrialization, have ramped up ever since. For the past century, some scientists have estimated an average of 200 extinctions per 10,000 species— levels so high that they believe they portend a mass extinction, a term reserved for geological events of the scale of the ordeal that annihalated the dinosaurs 66 million years ago. Yet some scientists, including the authors of those estimates, caution that even these numbers are conservative. The figures are based on the Red List compiled by the International Union for Conservation of Nature, or IUCN, a bookkeeper of species and their conservation statuses. As several experts have noted, the organization is slow to declare species extinct, wary that if the classification is wrong, they may cause threatened species to lose protections.

The Red List doesn’t include undescribed species, which some estimate could account for roughly 86 percent of the possibly 8.7 million species on Earth. That’s partly due to the sheer numbers of the largest species groups like invertebrates, plants, and fungi, especially in the little-explored regions around the tropics. It’s also because there are increasingly fewer experts to describe them due to a widespread lack of funding and training, noted conservation ecologist Natalia Ocampo-Peñuela of the University of California, Santa Cruz. Ocampo-Peñuela told Undark that she has no doubt that many species are going extinct without anyone noticing. “I think it is a phenomenon that will continue to happen and that it maybe has happened a lot more than we realize,” she said.

Studies of animal and plant specimens in museum and herbaria collections can uncover some of these dark extinctions. This can happen when scientists take a closer look at or conduct DNA analysis on specimens believed to represent known species and realize that these have actually been mislabeled, and instead represent new species that haven’t been seen in the wild in decades. Such a case unfolded recently for the ichthyologist Wilson Costa of the Federal University of Rio de Janeiro, who has long studied the diversity of killifish inhabiting southeastern Brazil’s Atlantic Forest. These fish live in shady, tea-colored acidic pools that form during the rainy season and lay eggs that survive through the dry period. These fragile conditions make these species extremely vulnerable to changes in water supply or deforestation, Costa wrote to Undark via email.

In 2019, Costa discovered that certain fish specimens collected in the 1980s weren’t members of Leptopanchax splendens, as previously believed, but actually represented a new species, which he called Leptopanchax sanguineus. With a few differences, both fish sport alternating red and metallic blue stripes on their flanks. While Leptopanchax splendens is critically endangered, Leptopanchax sanguineus hasn’t been spotted at all since its last collection in 1987. Pools no longer form where it was first found, probably because a nearby breeding facility for ornamental fish has diverted the water supply, said Costa, who has already witnessed the extinctions of several killifish species. “In the case discussed here, it was particularly sad because it is a species with unique characteristics and unusual beauty,” he added, “the product of millions of years of evolution stupidly interrupted.”

Similar discoveries have come from undescribed specimens, which exist in troves for diverse and poorly-studied groups of species, such as the land snails that have evolved across Pacific Islands. The mollusk specialist Alan Solem estimated in 1990 that, of roughly 200 Hawaiian species of one snail family, the Endodontidae, in Honolulu’s Bishop Museum, fewer than 40 had been described. All but a few are now likely extinct, said University of Hawaii biologist Robert Cowie, perhaps because invasive ants feasted off the snails’ eggs, which this snail family carries in a cavity underneath their shells. Meanwhile, Cheek said he’s publishing more and more new plant species from undescribed herbaria specimens that are likely already extinct in the wild.

Sometimes, though, it’s hard to identify species based on individual specimens, noted botanist Naomi Fraga, who directs conservation programs at the California Botanic Garden. And describing new species is not often a research priority. Studies that report new species aren’t often cited by other scientists, and they typically also don’t help towards pulling in new funding, both of which are key to academic success, Cheek said. One 2012 study concluded it takes an average of 21 years for a collected species to be formally described in the scientific literature. The authors added that if these difficulties — and the general dearth of taxonomists — persist, experts will continue to find extinct species in museum collections, “just as astronomers observe stars that vanished thousands of years ago.”

Museum records may only represent a fraction of undescribed species, causing some scientists to worry that many species could disappear unnoticed. For some groups, like snails, this is less likely, as extinct species may leave behind a shell that serves as a record of their existence even if collectors weren’t around to collect live specimens, noted Cowie. For instance, this allowed scientists to identify nine new and already-extinct species of helicinid land snails by combing the Gambier Islands in the Pacific for empty shells and combining these with specimens that already existed in museums. However, Cowie worries about the many invertebrates such as insects and spiders that won’t leave behind long-lasting physical remains. “What I worry about is that all this squishy biodiversity will just vanish without leaving a trace, and we’ll never know existed,” Cowie said.

Even some species that are found while they are still alive are already on the brink. In fact, research suggests that it’s precisely the newly described species that tend to have the highest risk of going extinct. Many new species are only now being discovered because they’re rare, isolated, or both — factors that also make them easier to wipe out, said Fraga. In 2018 in Guinea, for instance, botanist Denise Molmou of the National Herbarium of Guinea in Conakry discovered a new plant species which, like many of its relatives, appeared to inhabit a single waterfall, enveloping rocks amid the bubbly, air-rich water. Molmou was the last known person to see it alive.

Just before her team published their findings in the Kew Bulletin last year, Cheek looked at the waterfall’s location on Google Earth. A reservoir, created by a hydroelectric dam downriver, had flooded the waterfall, surely drowning any plants there, Cheek said. “Had we not got in there, and Denise had not gotten that specimen, we would not know that that species existed,” he added. “I felt sick, I felt, you know, it’s hopeless, like what’s the point?” Even if the team had known at the point of discovery that the dam was going to wipe it out, Cheek said, “it’d be quite difficult to do anything about it.”

While extinction is likely for many of these cases, it’s often hard to prove. The IUCN requires targeted searches to declare an extinction — something that Costa is still planning on doing for the killifish, four years after its discovery. But these surveys cost money, and aren’t always possible.

Meanwhile, some scientists have turned to computational techniques to estimate the scale of dark extinction, by extrapolating rates of species discovery and extinctions among known species. When Chisholm’s group applied this method to the estimated 195 species of birds in Singapore, they estimated that 9.6 undescribed species have vanished from the area in the past 200 years, in addition to the disappearance of 58 known species. For butterflies in Singapore, accounting for dark extinction roughly doubled the extinction toll of 132 known species.

Using similar approaches, a different research team estimated that the proportion of dark extinctions could account for up to just over a half of all extinctions, depending on the region and species group. Of course, “the main challenge in estimating dark extinction is that it is exactly that: an estimate. We can never be sure,” noted Quentin Cronk, a botanist of the University of British Columbia who has produced similar estimates.

Considering the current trends, some scientists doubt whether it’s even possible to name all species before they go extinct. To Cowie, who expressed little optimism extinctions will abate, the priority should be collecting species, especially invertebrates, from the wild so there will at least be museum specimens to mark their existence. “It’s sort of doing a disservice to our descendants if we let everything just vanish such that 200 years from now, nobody would know the biodiversity — the true biodiversity — that had evolved in the Amazon, for instance,” he said. “I want to know what lives and lived on this Earth,” he continued. “And it’s not just dinosaurs and mammoths and what have you; it’s all these little things that make the world go round.”

Other scientists, like Fraga, find hope in the fact that the presumption of extinction is just that — a presumption. As long as there’s still habitat, there’s a slim chance that species deemed extinct can be rediscovered and returned to healthy populations. In 2021, Japanese scientists stumbled across the fairy lantern Thismia kobensis, a fleshy orange flower only known from a single specimen collected in 1992. Now efforts are underway to protect its location and cultivate specimens for conservation.

Fraga is tracking down reported sightings of a monkeyflower species she identified in herbaria specimens: Erythranthe marmorata, which has bright yellow petals with red spots. Ultimately, she said, species are not just names. They are participants of ecological networks, upon which many other species, including humans, depend.

“We don’t want museum specimens,” she said. “We want to have thriving ecosystems and habitats. And in order to do that, we need to make sure that these species are thriving in, you know, populations in their ecological context, not just living in a museum.”

Katarina Zimmer is a science journalist. Her work has been published in The Scientist, National Geographic, Grist, Outside Magazine, and more.

This article was originally published on Undark. Read the original article.

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Today, elephants roam the savannas of Africa and rainforests in Asia, but elephant ancestors once lived in Europe and North America before going extinct like the region’s other ancient megafauna. Scientists and a team of volunteers recently uncovered a prehistoric elephant graveyard in northern Florida near Gainesville. 

[Related: Elephants and humans share surprising similarities. A new docuseries dives deep into that relationship.]

Roughly five and a half million years ago, several extinct relatives of elephants called gomphotheres died in or near a now dried up river. Today,  their fossils are giving scientists a unique view into prehistoric Florida.  

“This is a once-in-a-lifetime find,” curator of vertebrate paleontology at the Florida Museum of Natural History Jonathan Bloch said in a statement. “It’s the most complete gomphothere skeleton from this time period in Florida and among the best in North America.”

Collectively, proboscideans include modern elephants and their extinct relatives. They were found on every continent before humans even arrived, and the gomphotheres like the ones found in Florida were among the most diverse. 

Gomphotheres first evolved about 23 million years ago in the early Miocene period and dispersed into Asia and Europe. They likely crossed the Bering land bridge into North America 16 million years ago, and then crossed into South America via the newly risen Isthmus of Panama around 13 million years later. Rapid climate change and overhunting from humans led to the gomphotheres’ extinction around the end of the last ice age. 

Teams of paleontologists and volunteers began digging at the Montbrook Fossil Dig in 2022. Portions of a gomphothere skeleton were uncovered early in the spring of 2022, and while isolated bones have been found at this site, paleontologists didn’t suspect any out of the ordinary finds until a volunteer found the fossilized foot of something very large.

“I started coming upon one after another of toe and ankle bones,” said retired chemistry teacher and volunteer fossil-hunter Dean Warner. “As I continued to dig, what turned out to be the ulna and radius started to be uncovered. We all knew that something special had been found.”

The team found several complete skeletons, including one adult and at least seven juveniles, within the next few days. The skeletons will need to be fully excavated before their size can be accurately determined, but Bloch estimates that the adult animal was about eight feet tall at its shoulders.  The skull measures over nine feet long with tusks included. 

The elephants were likely deposited or transported to the area over time. “Modern elephants travel in herds and can be very protective of their young, but I don’t think this was a situation in which they all died at once,” said Rachel Narducci, the collection manager of vertebrate paleontology at the Florida Museum. “It seems like members of one or multiple herds got stuck in this one spot at different times.”

[Related: Extinct ‘thunder beasts’ went from mini to massive in the blink of an evolutionary eye.]

These fossil beds are about 30 miles inland from the Gulf of Mexico, but this area was closer to the sea when these bones were deposited during the late Miocene. This period of Earth’s history was marked by higher temperatures and sea levels. Remnants of ancient land-dwelling camels, rhinoceroses, and llamas are encased next to fresh and saltwater fish, turtles, alligators, and burrowing shrimp. This long-gone Florida river cut through limestone, and fossils of older marine species like sharks are occasionally found in the ancient remnants of its bed.  

The Montbrook gomphothere represents a new opportunity for scientists to learn about the long lost fauna of North America.

“The best part has been to share this process of discovery with so many volunteers from all over the state of Florida,” Bloch said. “Our goal is to assemble this gigantic skeleton and put it on display, taking its place alongside the iconic mammoth and mastodon already at the Florida Museum of Natural History.”

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Cold weather is prime time for humans to stay inside and snuggle up with loved ones. For our primate cousins, cuddling may even keep them healthy, as frosty temps and social bonds seem to go together like hot chocolate and marshmallows. Chilly temperature behavior, as it turns out, may also alter the course of evolution.

A study published June 1 in the journal Science found that a species’ long-term adaptation to life in extremely cold climates led to the evolution of successful social behaviors. Asian colobines living in colder regions saw genetic changes and adaptations to their social behaviors including extended care by mothers, which increased infant survival and the primates’ ability to live in the large complex multilevel societies we see today.

[Related: These primate ancestors were totally chill with a colder climate.]

An international team of researchers from the United States, China, the United Kingdom, and Australia studied how langurs and odd-nosed monkeys adapted over time. These members of the colobine family are leaf-eating monkeys that have been on Earth for about 10 million years. Their ancient ancestors dispersed across the planet’s continents and learned to live in tropical, temperate, and colder climates. 

“Virtually all primates are social and live in social groups,” study co-author and  University of Illinois Urbana-Champaign anthropologist Paul A. Garber said in a statement. “But the groups differ in size and cohesiveness. There are those that live in units of two or three individuals and others living in communities of up to 1,000 individuals.”

According to Garber, genomic studies suggest that the harem unit of organization—one male with two or more females and their offspring—was the ancestral norm for Asian colobines. Males are intolerant of other rival males and will fight to protect their turf. In some species, the females will stay with their natal group, while in others, both sexes leave to join or form new harems.

More complex societies formed over time. Some odd-nosed monkeys still form harems, but aren’t territorial. “This means their group territories can overlap and there are times they may come together to forage, rest and travel,” said Garber. 

Snub-nosed monkeys form a multilevel or modular society where multiple harems remain together throughout the year and create a large, cohesive breeding band. The team on this study recorded a society of about 400 individuals and breeding between individuals from different harems was common in golden snub-nosed monkeys. This inter-harem breeding happened roughly 50 percent of the time.

The study used ecological, geological, fossil, behavioral, and genomic analyses, and found that the colobine primates that lived in colder places tended to live in larger and more complex social groups. The glacial periods over the past six million years likely promoted the selection of genes that are involved in cold-related energy metabolism and hormonal regulation in the nervous system.

[Related: Baboons can recover from childhood trauma with a little help from their friends.]

Black-and-white snub-nosed monkeys in some parts of China live in low-oxygen elevations up to about 13,500 feet where night time temperatures can drop below zero on the coldest evenings. The Odd-nosed monkeys living in extremely cold locations developed more efficient pathways for dopamine and oxytocin. Oxytocin particularly is an important neurohormone for social bonding and this hormonal efficiency may lengthen the time a mother monkey takes care of her baby. This led to longer periods of breast-feeding and increase in infant survival.  

These adaptive changes appear to have further strengthened the relationships between individual monkeys, increased tolerance between males, and encouraged the evolution of more complex and larger multi level societies that go a long way. Strong social bonds can even help gut bacteria health in some monkeys.

In future studies, the team is interested in studying how changes in mating and social behavior may be the result of genetic changes from past environments and other social factors from the past. 

“With climate change becoming an hugely important environmental pressure on animals, it is hoped that this study will raise awareness for the need to investigate what course social evolution will take as the prevailing climate changes,” study co-author and University fo Western Australia biological anthropologist Cyril Grueter said in a statement. “Our finding that complex multilevel societies have roots stretching back to climatic events in the distant evolutionary past also has implications for a reconstruction of the human social system which is decidedly multilevel.”

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The fictional and deadly Jurassic Park has nothing on the real-life Dinosaur Cove on the southern tip of Victoria, Australia. Using bones from the fossil-filled hotspot, a team of paleontologists have confirmed that pterosaurs—more commonly known as pterodactyls—flew over Australian skies as far back as 107 million years ago. Their findings are detailed in a study published May 31 in the journal History Biology.

[Related: This pterosaur ancestor was a tiny, flightless dog-like dinosaur.]

The team examined two pieces of prehistoric bone that were extracted from Dinosaur Cove over 30 years ago. The bones belonged to two different pterosaurs, and were examined by experts from Curtin University in Perth and Melbourne’s Museums Victoria. A partial pelvis bone belonged to a pterosaur with a wingspan over 6.5 feet, and the smaller wing bone belonged to a juvenile pterosaur. These bones turned out to be the oldest remains of the giant winged reptiles ever recovered in Australia, which is better known for its larger sauropod fossils. 

Closely related to dinosaurs, pterosaurs soared through the skies during the Mesozoic Era, about 252 million years ago.

“During the Cretaceous Period (145–66 million years ago), Australia was further south than it is today, and the state of Victoria was within the polar circle—covered in darkness for weeks on end during the winter. Despite these seasonally harsh conditions, it is clear that pterosaurs found a way to survive and thrive,” study co-author and Curtin University PhD student Adele Pentland said in a statement. 

According to Pentland, remains of pterosaurs are a rare find worldwide. Even fewer remains have been discovered at regions that were once high paleolatitude locations, including Victoria. She told CNN that less than 25 sets of pterosaur remains from four species have been found in Australia since the 1980s, compared to more than 100 sets in countries like Argentina and Brazil.  

“So these bones give us a better idea as to where pterosaurs lived and how big they were. By analyzing these bones, we have also been able to confirm the existence of the first ever Australian juvenile pterosaur, which resided in the Victorian forests around 107 million years ago,” said Pentland.

[Related: The biggest animal ever to fly was a reptile with a giraffe-like neck.]

The specimens were found in the 1980s in a Dinosaur Cove expedition led by paleontologists Tom Rich and Pat Vickers-Rich. Their discovery of big-eyed dinosaurs along this area of coastline helped spark a major shift in how dinosaurs were more generally perceived. These “dinosaurs of darkness” gave paleontologists a glimpse of survival without sunlight and reframed questions about whether dinosaurs were warm-blooded creatures. 

“These two fossils were the outcome of a labor-intensive effort by more than 100 volunteers over a decade,” Tom Rich said in a statement. “That effort involved excavating more than 60 meters [196 feet] of tunnel where the two fossils were found in a seaside cliff at Dinosaur Cove.”

The biggest pterosaur scientists know of so far is Quetzalcoatlus northropi, which was found in Texas. Since everything is bigger in Texas, this pterosaur had a wingspan of about 32 to 36 feet. Australia’s largest pterosaur is the Thapunngaka shawi. It was discovered in 2021 by a team from the University of Queensland and boasts a wingspan of roughly 22 feet. 

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Over three million years ago, a 500-plus pound marsupial roamed Australia, winning the prize of the continent’s first long-distance walking champion. In a study published May 31 in the Journal of Royal Society Open Science, a team of scientists described the discovery of this new genus using advanced 3D scans and the partial remains of a 3.5 million year old specimen. 

Most earlier studies on this group have focused on its skull since other skeletal remains are rare in Australia’s fossil record. The skeleton described in this new study, found at Kalamurina Station in southern Australia in 2017, is special since it is the first that was found with associated soft tissue structures. The authors used 3D-scanning to compare the partial skeleton with other diprotodontid material housed in collections all over the world. A hard concretion that formed shortly after the animal died encased its foot, and CT scans revealed the soft tissue impressions on the outline of its footpad.

[Related: Giant wombats the size of small cars once roamed Australia.]

The new genus Ambulator, meaning “walker” or “wanderer,” had four giant legs which would have helped it roam long distances in search of food and water compared to its earlier relatives. It belongs to the Diprotodontidae family, an extinct family of big, four-legged, herbivorous marsupials that lived in New Guinea and Australia. The largest species was Diprotodon optatum, which was about the size of a car and weighed almost 6,000 pounds. Diprotodontids were an integral part of the region’s ecosystem before going extinct about 40,000 years ago. 

“Diprotodontids are distantly related to wombats – the same distance as kangaroos are to possums – so unfortunately there is nothing quite like them today. As a result, paleontologists have had a hard time reconstructing their biology,” study author and Flinders University PhD student Jacob van Zoelen said in a statement. 

Ambulator keanei lived during the Pliocene era when Australia saw an increase in grasslands and open habitats become more dry. To have enough to eat and drink, diprotodontids likely had to travel great distances. 

“We don’t often think of walking as a special skill but when you’re big any movement can be energetically costly so efficiency is key,” said van Zoelen. “Most large herbivores today such as elephants and rhinoceroses are digitigrade, meaning they walk on the tips of their toes with their heel not touching the ground.  “

Diprotodontids are plantigrade animals, which means that their heel-bone makes contact with the ground as they walk. This is similar to the way humans walk and helps distribute the weight while walking, but does use more energy when running. According to van Zoelen, diprotodontids also have extreme plantigrady in their hands. The bone of the wrist is modified into a secondary heel and this “heeled hand” may have made early reconstructions of the animal look a little bit bizarre.

“Development of the wrist and ankle for weight-bearing meant that the digits became essentially functionless and likely did not make contact with the ground while walking.” said van Zoelen. “This may be why no finger or toe impressions are observed in the trackways of diprotodontids.”

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Over the first two years of the COVID-19 pandemic, the coronavirus directly or indirectly killed about 15 million people worldwide, according to estimates from the World Health Organization. In the United States, more people died in 2020 and 2021 than during the 1918 influenza pandemic, which was widely called the most deadly in recorded history. 

The word “deadly” certainly applies to the virus that causes COVID-19. And yet, epidemiologists hesitate to give SARS-CoV-2 the superlative of deadliest virus in human history. To them, the raw number of mortalities caused by a given virus doesn’t always paint the full picture of a pathogen’s danger—especially when comparing viral outbreaks across time.

Raw mortality numbers have to be taken in the context of the world’s total population, says Jennifer Nuzzo, professor of epidemiology and director of the Pandemic Center at Brown University School of Public Health. “A lot of people talk about how COVID deaths eclipsed what we saw in 1918,” she says. “It’s really important to remember that the population of 1918 was a fraction of what it is today.” In that context, the flu of 1918 rises back up in the ranks in terms of deadliness.

Using the “case fatality rate” metric to determine what virus is the deadliest, rabies would likely come out on top. That’s because, if an infection becomes symptomatic, rabies is fatal to humans in more than 99 percent of cases. Globally, approximately 59,000 people die from rabies every year. Very few of those deaths—an average of two in the US—occur in the developed world because of rabies vaccines for household pets and swift medical interventions after bites.

But “a virus doesn’t have to have a very high case fatality ratio to cause a tremendous amount of death and disruption,” Nuzzo says. “It’s more about looking at the environments in which the viruses are spreading, and our social and human vulnerabilities to it.” 

A virus with a lower case fatality rate can kill more people if it’s highly transmissible, with a long period of time before severe or obvious symptoms set in. This allows an infected person to expose many others. That’s why SARS-CoV-2 caused such a rapid and devastating outbreak around the globe. It’s easily transmitted via airborne droplets, and doesn’t always or immediately cause severe illness. 

[Related: Can viruses be good for us?]

Globalization sped it along, too. “When a virus spreads at the pace of a human being walking, that’s very different than when you can hop on an airplane and be anywhere in the world in 36 hours,” Nuzzo says. 

During large outbreaks such as epidemics or pandemics, epidemiologists look at another metric, called excess deaths: how many more people died during a period of time than typically do over that same window. Excess deaths can account for other indirect ways that a virus causes death, Nuzzo says, such as patients who need critical care but can’t get it in overburdened hospitals.

Here’s how some of the most devastating viruses in human history tell different stories of how high a death toll can rise:

Influenza

The 1918 influenza pandemic still far and away ranks as the deadliest global outbreak of the 20th century. Thought to be caused by an H1N1 virus, it spread globally in 1918 and 1919. An estimated 500 million people were infected (approximately a third of the global population) and 50 million people died worldwide, about 675,000 of whom were in the United States, according to the Centers for Disease Control and Prevention. 

Without sophisticated testing and tracking, death toll estimates rely heavily on excess death calculations. Some suggest the true toll was closer to 17 million, while others set it much higher at 100 million. William Schaffner, professor of preventive medicine and professor of medicine in the division of infectious diseases at the Vanderbilt University School of Medicine, cautions against over-interpreting comparisons between the historic flu data and modern viral outbreaks.

[Related: Can you get diseases from bad bathroom smells?]

 “We are determining cases and even counting deaths with much more precision now than we did then,” he says. At the time, there were also no flu vaccines and no antibiotics to treat secondary bacterial infections, which likely drove the excess death toll higher.

Today, the youngest and oldest people are most likely to die from influenza. But during the pandemic over 100 years ago, Schaffner says, deaths bore a different signature: mortality peaked among young and middle-aged adults, too. Why that happened is still unclear, he says, but it contributed to the historic toll of that pandemic.

Influenza continues to hold its place as one of the deadliest viruses, despite the availability of vaccines. Variants of the influenza virus have led to other pandemic-level events, such as the 2009 outbreak colloquially called the swine flu pandemic. But the virus is also endemic in our society, and infects an estimated 1 billion people globally every year, according to the World Health Organization. Of those cases, the WHO reported in 2019, somewhere between 290,000 to 650,000 result directly or indirectly in deaths. 

An estimated 40.1 million people have died from AIDS-related illnesses since the start of the epidemic, according to the Joint United Nations Program on HIV and AIDS. That is nearly half of the number of people estimated to have become infected with HIV since the start of the epidemic, at an estimated 84.2 million. 

The case fatality rate of HIV/AIDS was historically quite high. Some estimates put it around 80 percent without treatment. But much has changed since the 1980s. Today, there are ways to manage HIV and mitigate the immunodeficiencies associated with an infection, and most patients are diagnosed sooner after an infection. In the United States, the rate of HIV-related deaths fell by nearly half from 2010 to 2017, according to the CDC. 

That excess deaths metric likely reached a much higher number by the time officials declared the public health emergency over in early May. The Omicron wave that swept around the globe in late 2021 and early 2022 saw one of the largest surges in cases of COVID-19 and, although the variant didn’t seem to be more deadly than previous variants, with millions of people infected, a high death toll in the hundreds of thousands was inevitable. 

Early in the pandemic, the case fatality rates calculated for SARS-Cov-2 varied considerably. Many estimates were likely higher than the true number, as researchers scrambled to devise tests for the virus and milder cases slipped through the cracks. In early 2020, estimates of the case fatality rate by country ranged as high as 25 percent or more. Since then, case fatality rates have dropped, and now, according to Johns Hopkins University, they are as high as 4.9 percent. In the US, the case fatality rate is 1.1 percent. 

Mortalities continued to stack up into the 20th century, with an average of three out of every 10 people infected dying. The disease, which is caused by variola virus, is estimated to have killed more than 300 million people from 1900, until a global vaccination campaign halted its path of devastation in 1977. It was the first disease ever to be eradicated. 

[Related: The first honeybee vaccine could protect the entire hive, starting with the queen]

But it was the very thing that made it particularly fearsome that was its downfall, Schaffner says. “It created such a distinctive rash that people could identify it and fear it. And that was one of its Achilles heels,” he says. Because it was so easily identifiable, and spread so slowly, vaccinating the local population near an outbreak swiftly curtailed transmission. Such an approach, he says, was part of the vaccination strategy that eradicated the great pestilence. 

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The persistent pathogen known as the plague was circulating around Europe and Asia centuries before it wiped out about 25 million people. A team of scientists have just recently found 4,000 year-old DNA belonging to Yersinia pestis, or the bacteria that causes the plague. That’s about 3,000 years before the plague before the Black Death began. The findings were detailed in a study published May 30 in the journal Nature Communications and represent the oldest evidence of the plague in Britain found to date. 

[Related: Scientists tracked the plague’s journey through Denmark using really old teeth.]

The team identified two cases of Yersinia pestis (Y. pestis) from human remains found uncovered in a mass burial site in southwest England near Somerset and another in a ring cairn monument in Cumbria in northwest England. After taking small skeletal samples from 34 individuals at both sites, they screened for plague bacteria in the teeth. Dental pulp can trap the DNA remnants of infectious diseases and has helped scientists find evidence of the plague before. 

After extracting dental pulp, they analyzed the DNA inside and identified three cases of Y. pestis in two children that are estimated to be about 10 to 12 years-old when they died, as well as one case in a woman who was between 35 and 45 years-old. It is likely that these people lived at roughly the same time, according to radiocarbon dating.  

“The ability to detect ancient pathogens from degraded samples, from thousands of years ago, is incredible. These genomes can inform us of the spread and evolutionary changes of pathogens in the past, and hopefully help us understand which genes may be important in the spread of infectious diseases,” study co-author and PhD student from the Francis Crick Institute Pooja Swali said in a statement. “We see that this Yersinia pestis lineage, including genomes from this study, loses genes over time, a pattern that has emerged with later epidemics caused by the same pathogen.”

Plague has been identified in multiple individuals who lived in Eurasia between 5,000 and 2,500 years ago during the Late Neolithic and Bronze Age (LNBA). Evidence of the plague, however, hadn’t been seen in Britain at this point in time. This LNBA strain was likely brought into Central and Western Europe about 4,800 years ago as humans expanded into Eurasia, and this study suggests it extended even further west into Britain. The LNBA strain’s wide geographic range suggests that it could have been easily transmitted.

Genome sequencing found that the strain of Y. pestis found in these sites looks very similar to the strain identified further east into Eurasia at the same time and not later strains of the disease. It lacked the yapC and ymt genes, which are both seen in later strains of plague. The ymt gene is also known to play an important role in plague transmission via fleas. It is likely that the LNBA strain was not transmitted on fleas, unlike later strains of the plague, such as the one that caused the Black Death in the Fourteenth Century. 

[Related: You could get the plague (but probably won’t).]

The team is not fully certain that the individuals at these old burial sites were infected with the exact same strain of plague, since pathogenic DNA that causes disease degrades very quickly in samples that could be incomplete or eroded. 

The Somerset site is also rare since it doesn’t match other funeral sites dating back to this time period. The individuals buried there appear to have died from trauma. The team believes that the mass burial here was not due to an outbreak of plague, but the individuals studied may have been infected when they died.  

“We understand the huge impact of many historical plague outbreaks, such as the Black Death, on human societies and health, but ancient DNA can document infectious disease much further into the past,” co-author and geneticist at the Francis Crick Institute Pontus Skoglund said in a statement. “Future research will do more to understand how our genomes responded to such diseases in the past, and the evolutionary arms race with the pathogens themselves, which can help us to understand the impact of diseases in the present or in the future.”

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Efficiently standing up and walking and running on two feet  stands out among the traits that separates Homo sapiens from great apes—and we can owe a lot of that to a raised medial arch. While crucial, the mechanics behind bipedal walking are still a bit of an evolutionary mystery.  A study published May 30 in the journal Frontiers in Bioengineering and Biotechnology found that helpful and spring-like arches may have evolved for the purpose of helping us walk on two feet.

[Related: Foraging in trees might have pushed human ancestors to walk on two feet.]

The team found that the recoil of a flexible arch repositions in the ankle upright for more efficient walking and is particularly effective for running. 

“We thought originally that the spring-like arch helped to lift the body into the next step,” study co-author and University of Wisconsin-Madison biomechanical engineer Lauren Welte said in a statement. “It turns out that instead, the spring-like arch recoils to help the ankle lift the body.”

The raised arch in the center of the human foot is believed to give hominins more leverage while walking upright. When arch motion is restricted, like it could be in those with more flat feet, running demands more energy from the body. Arch recoil could potentially make our species more efficient by propelling the body’s center of mass forward, essentially making up for the mechanical work that the muscles would have to do otherwise.

In this new study, the team selected seven participants with varying arch mobility and filmed their walking and running patterns with high-speed x-ray motion capture cameras. The team measured the height of each participant’s arch and took CT scans of their right feet. They also created rigid models that were compared to the measured motion of the bones in the foot. Scientists then measured which joints added the most to arch recoil and the contribution of arch recoil to center of mass and ankle propulsion.

Surprisingly, they found that a rigid arch without recoil caused the foot to prematurely leave the ground, likely decreasing the efficiency of the calf muscle. A rigid arch also leaned the ankle bones too far forward. A forward lean looks more like the posture of walking chimpanzees instead of the straight upright stance of a human gait.

A flexible arch helped reposition the ankle upright, allowing the leg to push off the ground more effectively. This effect is greater while running, suggesting that a flexible arch for more efficient running may have been a desired evolutionary trait.

The team also found that a joint between two bones in the medial arch–the navicular and the medial cuneiform–is crucial to flexibility. Investigating the changes in this joint over time could help scientists track the development of bipedalism in our own fossil record. 

[Related: The Monty Python ‘silly walk’ could replace your gym workout.]

“The mobility of our feet seems to allow us to walk and run upright instead of either crouching forward or pushing off into the next step too soon,” study co-author and Queen’s University mechanical and materials engineer Michael Rainbow said in a statement.

These findings and understanding more about arch flexibility could help people who have rigid arches due to illness or injury. Their hypothesis still needs more testing, but could help solve a plethora of modern-day foot dilemmas. 

“Our work suggests that allowing the arch to move during propulsion makes movement more efficient,” said Welte. “If we restrict arch motion, it’s likely that there are corresponding changes in how the other joints function.”

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As they creep through tropical environments appearing not to have a care in the world, sloths give off some of the chillest vibes in the animal kingdom. This relaxed and elusive nature does make studying sloths a bit difficult, but a study published May 29 in the journal PeerJ Life & Environment is shedding some new light on activity patterns and behaviors adaptations of two sloth species.

[Related: Sloths aren’t the picky eaters we thought they were.]

The team looked at Bradypus variegatus and Choloepus hoffmanni, two sloth species that live in the lowland rainforests of Costa Rica’s Caribbean coast. Costa Rica is home to six species of sloths, who have the slowest digestive system of any animal on Earth. It can take the mammals two weeks to digest an entire meal, and they sleep about 20 hours a day to conserve energy. 

Using micro data loggers, the team continuously monitored the behavior of both three-toed sloths (Bradypus) and two-toed sloths (Choloepus) for periods ranging from days to weeks. These recordings enabled the team to explore how fluctuating environmental influences sloth activity and how that correlates with their uniquely chill and low-energy lifestyle. 

Choloepus sloths are cathemeral, meaning that they have irregular variable periods of activity throughout a 24-hour cycle. Cathemeral behavior allows them to take advantage of better environmental conditions while minimizing the risk of predation. 

The study also observed a large amount of variability in activity levels between the animals and also within individual sloths. This flexibility suggests that the animals have developed diverse strategies to adapt to their surroundings, which enhances their chances of survival when the environment fluctuates. 

The team initially expected that daily temperatures, which can hit the mid-90s, would influence sloth activity, but their observations did not support that initial hypothesis. However, Bradypus sloths did increase their night time activity on colder nights and the nights that followed colder days. The authors believe that this indicates a potential correlation between sloth behavior and temperature variations.

[Related: Our bravest ancestors may have hunted giant sloths.]

While this study adds more understanding to sloth ecology, it also highlights the importance of preserving and protecting tropical rainforests and their unique inhabitants. According to Global Forest Watch, Costa Rica lost about 2.4 percent of its forest cover between 2000 and 2020, but the country has gained international recognition for its efforts to mitigate climate change and promote animal welfare.

“Understanding the drivers of sloth activity and their ability to withstand environmental fluctuations is of growing importance for the development of effective conservation measures, particularly when we consider the vulnerability of tropical ecosystems to climate change and the escalating impacts of anthropogenic activities in South and Central America,” the team wrote in the paper.

As these tropical ecosystems become more vulnerable due to human-made climate change, understanding wildlife patterns are crucial for conservation methods. While long-term observational research is a challenge, this study could pave the way for more studies on this cryptic and elusive species. 

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When it comes to the critical process of pollination, butterflies and especially bees are typically the most lauded participants. These pollinators fly from flower to flower to feed and fertilize plants by spreading pollen around. But, these fluttery creatures are far from the only species that help flowers reproduce and bloom. It turns out that some of nature’s most unsung and diverse pollinators are a type of long-snouted beetles called weevils.

[Related: Build a garden that’ll have pollinators buzzin’.]

A study published May 25 in the journal Peer Community in Ecology wiggles into the world of weevils, including some who spend their entire lifecycle in tandem with a specific plant they help pollinate. 

“Even people who work on pollination don’t usually consider weevils as one of the main pollinators, and people who work on weevils don’t usually consider pollination as something relevant to the group,” study co-author and assistant curator of insects at the Field Museum in Chicago said in a statement. “There are lots of important things that people are missing because of preconceptions.”

The quarter-of-an-inch long  weevils can be considered pests, especially when found munching on pasta and flour in pantries. Weevils used to find their way into the biscuits on Nineteenth Century ships that even highly ranked officers ate, as depicted in the 2003 seafaring film Master and Commander: The Far Side of the World. They can be so destructive that from 1829 to 1920, boll weevils completely disrupted the cotton economy in the South as they fed on cotton buds. 

Despite this less than stellar reputation, the insects are still beneficial to many of the world’s plant species. 

Scientists have identified roughly 400,000 species of beetles, making them one of the largest groups of animals in the world. Among this already big bunch of bugs, weevils are the largest group. “There are 60,000 species of weevils that we know about, which is about the same as the number of all vertebrate animals put together,” said de Medeiros.

The authors looked at 600 species of weevil, reviewing hundreds of previously published data on how weevils and plants interact to get a better sense of their role as prime pollinators. It focused on brood-site pollinators—insects that use the same plants that they pollinate as the breeding sites for their larvae. It is similar to the relationship between Monarch butterflies and milkweed, which is the only plant that Monarch caterpillars can eat. 

“It is a special kind of pollination interaction because it is usually associated with high specialization: because the insects spend their whole life cycle in the plant, they often only pollinate that plant,” said de Medeiros.  And because the plants have very reliable pollinators, they mostly use those pollinators.” 

[Related: This lawn-mowing robot can save part of your yard for pollinators.]

Unlike Monarchs, brood-site pollinators take the relationship with the plant a step further. They rely on only one plant partner as a source for both food and egg laying, unlike adult Monarchs who will eat the nectar of many different types of flowers. 

“This kind of pollination interaction is generally thought to be rare or unusual,” said de Medeiros. “In this study, we show that there are hundreds of weevil species and plants for which this has been documented already, and many, many more yet to be discovered.”

The relationship like the one between weevils and their plants means that they both need each other to flourish. Some industries, like palm oil,  have already hurt forests, therefore disturbing the animal species that rely on them. 

“Oil palm, which is used to make peanut butter and Nutella, was not a viable industry until someone figured out that the weevils found with them were their pollinators. And because people had an incorrect preconception that weevils were not pollinators, it took much, much longer than it could have taken,” said de Medeiros.

Misconceptions about weevils were one of this team’s motivations for the study. The team hopes that by summarizing what is known about the pollinators, more scientists and the general public appreciate the role of weevils as pollinators, particularly in the tropics. 

The post Move over, bees: The lowly weevil is a power pollinator appeared first on Popular Science.

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What is life? It’s a fuzzy concept without a single answer. If you asked a philosopher, they might quote Plato and tell you it’s the ability to support yourself and reproduce, though that would make sterile donkeys non-living objects. Ask a biologist and they’ll likely hit you with a textbook definition of life as organized matter with genes—as diverse as a paramecium and an elephant.  

Oliver Trapp, a professor of chemistry at the Ludwig Maximilian University of Munich in Germany, offers a different description. He says life is a “self-sustainable reaction network,” in which organisms have the processes necessary to survive and adapt. This is in line with the definition NASA uses when looking for extraterrestrial life. Having a clear idea of what makes up life, and the conditions needed to sustain it, helps astronomers get a better picture of what to look for when searching for life on other planets. 

Specifically, they could look for the environments that have collected the essential ingredients. Prerequisites to making life, based on what happened during early Earth, are materials for organic chemical reactions. In a new study published today in Scientific Reports, Trapp and his colleagues simulated how our planet received the supplies for life-producing chemical reactions 4.4 billion years ago. They suggest that no special or lucky conditions were necessary. Instead, life on Earth was created from volcanic particles and iron-rich meteorites. These carried the building blocks essential to living things: amino acids, lipids, nucleosides, and sugars.

[Related: Here’s how life on Earth might have formed out of thin air and water]

“Understanding the origins of biology is one of the greatest unsolved scientific questions. It has important implications for understanding how common life may be beyond Earth and for understanding humanity’s place in the universe,” says Henderson (Jim) Cleaves, a chemistry professor at Tokyo Institute of Technology and president of the International Society for the Study of the Origins of Life, who was not involved in the study.

Previous theories suggested that Earth’s volcanoes were the starting points. Lava shaped the continents, and volcanic gases helped create oceans and atmosphere. Early Earth may have had another important boost, too, in the form of chemical-rich meteors falling from the sky. 

Trapp’s new study suggests it was the iron from fallen asteroids that helped convert atmospheric carbon dioxide into organic molecules such as hydrocarbons, aldehydes, and alcohol. “The meteorites entered the dense atmosphere, heated up and then you have this ablation of nanoparticles,” he explains. The natural minerals found on volcanoes would have helped support these chemical reactions.

To determine the interplay of space rocks and Earthly eruptions, the authors simulated the conditions of our young planet in the lab. They purchased chunks of two iron and stony meteorites and dissolved them in acid to create a solution, and soaked in crushed samples of volcanic ash and minerals assumed to have been present billions of years ago. The result was a model of meteorites crash landing on volcanic islands. The team also simulated atmospheric conditions on early Earth by combining carbon dioxide gas with hydrogen gas or water under a high-pressure and high-heat system. 

[Related: A new finding raises an old question: Where and when did life begin?]

Observing the reactions in this pressurized model, the team noticed an increase in the production of aldehydes, formaldehydes, alcohol, hydrocarbons, and acetaldehyde. These organic compounds would then be used in further chemical reactions to make amino acids, lipids, DNA, and RNA molecules. “Even at lower temperatures, the particles were highly reactive and quite robust,” Trapp says. The authors suggest that as Earth’s atmosphere cooled down and became more reactive, it was probably easier for iron to speed along the conversion of carbon dioxide into oxygen-containing organic compounds. 

“It is very interesting to see a demonstration of how micrometeorites could have contributed to prebiotic organic synthesis during their infall,” notes Cleaves. While he says the work provides ample evidence for this theory of how life first emerged, he warns this simulation is dependent on the composition of the early atmosphere. It’s unclear if those conditions existed exactly how the lab simulated them, he says.

Trapp says the findings are a start to uncover what makes up life. As long as the right materials are present, the conditions to sustain living things may not be unique to Earth. This could help space explorers decide if a planet is worth exploring. For example, inactive volcanoes have already been spotted in other places like Jupiter’s moon Io and Europa—a strong contender for extraterrestrial life since it holds a liquid water ocean underneath its icy surface.  

Alternatively, these simulations could rule out otherwise promising worlds. “If a planet is cooling down too quickly and no longer able to convert carbon dioxide into organic compounds, this process would completely stop and essentially cause life to die.” Even if we do stumble on a planet with the optimal environment for life, whether we actually find aliens is another matter entirely.

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Behind a beautiful oil-on-canvas painting is, well, its canvas. To most art museum visitors, that fabric might be no more than an afterthought. But the canvas and its chemical composition are tremendously important to scientists and conservators who devote their lives to studying and caring for works of art.

When they examine a canvas, sometimes those art specialists are surprised by what they find. For instance, few conservators expected a 200-year-old canvas to contain proteins from yeast and fermented grains: the fingerprints of beer-brewing.

But those very proteins sit in the canvases of paintings from early 19th century Denmark. In a paper published on Wednesday in the journal Science Advances, researchers from across Europe say that Danes may have applied brewing byproducts as a base layer to a canvas before painters had their way with it.

“To find these yeast products—it’s not something that I have come across before,” says Cecil Krarup Andersen, an art conservator at the Royal Danish Academy, and one of the authors. “For us also, as conservators, it was a big surprise.”

The authors did not set out in search of brewing proteins. Instead, they sought traces of animal-based glue, which they knew was used to prepare canvases. Conservators care about animal glue since it reacts poorly with humid air, potentially cracking and deforming paintings over the decades.

[Related: 5 essential apps for brewing your own beer]

The authors chose 10 paintings created between 1828 and 1837 by two Danes: Christoffer Wilhelm Eckersberg, the so-called “Father of Danish Painting,” fond of painting ships and sea life; and Christen Schiellerup Købke, one of Eckersberg’s students at the Royal Danish Academy of Fine Arts, who went on to become a distinguished artist in his own right.

The authors tested the paintings with protein mass spectrometry: a technique that allows scientists to break a sample down into the proteins within. The technique isn’t selective, meaning that the experimenters could find substances they weren’t seeking.

Mass spectrometry destroys its sample. Fortunately, conservators in the 1960s had trimmed the paintings’ edges during a preservation treatment. The National Gallery of Denmark—the country’s largest art museum—had preserved the scraps, allowing the authors to test them without actually touching the original paintings.

Scraps from eight of the 10 paintings contained structural proteins from cows, sheep, or goats, whose body parts might have been reduced into animal glue. But seven paintings also contained something else: proteins from baker’s yeast and from fermented grains—wheat, barley, buckwheat, rye.

[Related: Classic Mexican art stood the test of time with the help of this secret ingredient]

That yeast and those grains feature in the process of brewing beer. While beer does occasionally turn up in recipes for 19th century house-paint, it’s alien to works of fine art.

“We weren’t even sure what they meant,” says study author Fabiana Di Gianvincenzo, a biochemist at the University of Copenhagen in Denmark and the University of Ljubljana in Slovenia.

The authors considered the possibility that stray proteins might have contaminated the canvas from the air. But three of the paintings contained virtually no brewer’s proteins at all, while the other seven contained too much protein for contamination to reasonably explain.

“It was not something random,” says Enrico Cappellini, a biochemist at the University of Copenhagen in Denmark, and another of the authors.

To learn more, the authors whipped up some mock substances containing those ingredients: recipes that 19th-century Danes could have created. The yeast proved an excellent emulsifier, creating a smooth, glue-like paste. If applied to a canvas, the paste would create a smooth base layer that painters could beautify with oil colors.

Eckersberg, Købke, and their fellow painters likely didn’t interact with the beer. The Royal Danish Academy of Fine Arts provided its professors and students with pre-prepared art materials. Curiously, the paintings that contained grain proteins all came from earlier in the time period, between 1827 and 1833. Købke then left the Academy and produced the three paintings that didn’t contain grain proteins, suggesting that his new source of canvases didn’t use the same preparation method.

The authors aren’t certain how widespread the brewer’s method might have been. If the technique was localized to early 19th century Denmark or even to the Academy, art historians today could use the knowledge to authenticate a painting from that era, which historians sometimes call the Danish Golden Age. 

This was a time of blossoming in literature, in architecture, in sculpture, and, indeed, in painting. In art historians’ reckoning, it was when Denmark developed its own unique painting tradition, which vividly depicted Norse mythology and the Danish countryside. The authors’ work lets them glimpse lost details of the society under that Golden Age. “Beer is so important in Danish culture,” says Cappellini. “Finding it literally at the base of the artwork that defined the origin of modern painting in Denmark…is very meaningful.” 

[Related: The world’s art is under attack—by microbes]

The work also demonstrates how craftspeople repurposed the materials they had. “Denmark was a very poor country at the time, so everything was reused,” says Andersen. “When you have scraps of something, you could boil it to glue, or you could use it in the grounds, or use it for canvas, to paint on.”

The authors are far from done. For one, they want to study their mock substances as they age. Combing through the historical record—artists’ diaries, letters, books, and other period documents—might also reveal tantalizing details of who used the yeast and how. Their work, then, makes for a rather colorful crossover of science with art conservation. “That has been the beauty of this study,” says Andersen. “We needed each other to get to this result.”

This story has been updated to clarify the source of canvases for Købke’s later works.

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Joel Cramer was at the pool with his kids when another dad, competing in a big splash contest, got up onto the diving board. He bounced up once, and when he landed on the board for the second time, his quadriceps muscle tore. “It rolled up his leg and balled up near the top of his thigh,” says Cramer, a professor of exercise physiology at the University of Nebraska. “[It was] like rolling up a window shade.”

That’s an extreme (and extremely rare) example of a muscle strain, a common injury that happens to high school soccer stars, recreational runners, and middle-aged racquetball players alike. “Strain” is the medical term for the condition, though it’s colloquially known as a pulled muscle. The term is a catch-all that covers everything from a small twinge to a full-on rupture.

What we call a “tear” and what we coin a “pull or strain” all boil down to the same type of injury: A rip to some part of the muscle. But some are worse than others. A mild or “grade one” strain—what many people call a “pulled muscle”—happens when you tear about 5 percent of the fibers in a particular muscle. This typically feels like an uncomfortable twinge that may force you off the court for a few weeks. A moderate sprain involves a higher percentage of fibers, and might sideline you for a month or more. A full rupture severs the muscle entirely, and usually requires surgery to repair.

[Related: Why do my muscles ache the day after a big workout?]

Okay, but how exactly do these tears occur? And why do some instances result in more muscle fiber damage than others? Cramer says three major factors contribute to this muscle busting. Muscles that cover two joints, like the hamstring which extends across the hip and knee joints, are at the highest risk. That’s because having both joints moving and stretching the muscle simultaneously adds tension, which can lead to strains.

Muscles are also more likely to strain while they are contracting. At this point, muscles are shortening and lengthening at the same time. During a dumbbell curl, for example, raising the weight up towards the shoulder compresses the bicep, and lowering it back down stretches it back out again. The muscle can create and sustain much more force during the lengthening portion of the activity, says Cramer, which makes it easier for it to strain.

Finally, muscles that have a higher proportion of fast-twitch to slow-twitch fibers strain more readily. Fast-twitch fibers contract quickly and generate more power, says Cramer. For that reason, they are the ones recruited for explosive tasks like sprinting. “It’s relatively uncommon for slow twitch [muscles] to strain,” he says. “They’re used to being active all the time.”

Technically, Cramer says, it’s possible to strain any of the skeletal muscles in your body. “For some, it’s not physiologically impossible, just very highly unlikely,” he says. “You’re probably not going to strain deep muscles with very specific functions.” The muscles in the finger, for example, are probably not going to cause much trouble, since they only have one task and don’t do much heavy lifting.

[Related: How to get muscle gains: A beginner’s guide to becoming buff]

Low flexibility and range of motion are major factors at risk for muscle strain, says Cramer. Despite the popular belief that larger muscles are tighter, Cramer says greater muscle mass is actually associated with greater give. “There’s evidence to suggest that weight training done with a good range of motion increases flexibility,” he says. And even though it may not seem like it when you’re struggling to touch your toes, Cramer says most people can teach their body to be springy enough to do the splits. So, to help keep your muscle fibers intact—pick up the weights and don’t skip your stretching routine, no matter how tedious it is.

How does a pulled muscle heal?

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The armadillo is beloved for its ability to scrunch itself up in a ball with their protective flexible shells. They’ve long been considered the only living mammals with these reptilian and fish-like suits of bony or scaly armor instead of hairy mammalian skin. However, a study published May 24 in the journal iScience, shows that African spiny mice actually produce the same spiny structures beneath the skin of their tails, which has gone largely undetected by scientists.

[Related: How science came to rely on the humble lab rat.]

African spiny mice are small to medium sized rodents with spiny hairs on their upper body, large eyes and ears, and scaly tails. Some species are found in Egypt, other parts of eastern Africa, Saudi Arabia, and Pakistan and while others are native to South Africa.  

A team of scientists made this spiny discovery while conducting routine CT scanning of museum specimens for the openVertebrate program. 

“I was scanning a mouse specimen from the Yale Peabody Museum, and the tails looked abnormally dark,” co-author and director of Florida Museum of Natural History’s digital imaging laboratory Edward Stanley said in a statement. 

Stanley initially assumed the discoloration was caused by an imperfection that was introduced when the specimen was preserved, but analysis of the X-Rays revealed an unmistakable feature that he was intimately familiar with.

“My entire PhD was focused on osteoderm development in lizards,” he said. “Once the specimen scans had been processed, the tail was very clearly covered in osteoderms.”

Osteoderms are the bony deposits that form scales or plates on the skin. They are also distinct from the scales of pangolins or the quills of hedgehogs and porcupines. These parts are composed of keratin, the same tissue that makes up hair, skin, and nails.

Osteoderms on spiny mice have been observed since the mid-1970s. A 2012 study demonstrated spiny mice can regenerate injured tissue without scarring. This ability is very common among reptiles and invertebrates, but was previously unknown in mammals. While mammalian skin is particularly fragile, spiny mice can heal twice as fast as their rodent relatives.

Spiny mice belong to four genera in the subfamily Deomyinae, but other than similarities in their DNA and possibly the shape of their teeth, scientists have been unable to find a single shared feature among the species of this group that distinguishes them from other rodents.

[Related: This newly discovered gecko can literally squirm right out of its skin.]

The team scanned additional museum specimens from all four genera and found that the spiny mice tails were covered in the same sheather of bone. Gerbils are the closest relatives of Deomyinae and they do not have osteoderms, which means that this trait likely evolved only once in the ancestor of spiny mice. 

“Spiny mice can regenerate skin, muscle, nerves, spinal cord and perhaps even cardiac tissue, so we maintain a colony of these rare creatures for research,” co-author and University of Florida biologist Malcolm Maden said in a statement. 

Maden and his team are mapping the genetic pathways that give spiny mice these healing powers to hopefully find a model for human tissue regeneration. The team further analyzed the development of spiny mice osteoderms and confirmed that they were similar to those of armadillos, but likely evolved independently. 

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One large part of managing egg-laying hens is a process called sexing, or determining the sex of a baby chick after it hatches. A study published May 22 in the journal PLOS ONE finds that fertilized chicken eggs can be sexed by “sniffing” the volatile chemicals that are emitted through the chicken’s shell.

About a day after hatching, chicks are sorted by sex. Male chicks are killed almost  immediately, a process that kills an estimated 6.5 billion male chicks per year. Sexing is largely used due to both economics and biology—male chickens are of little use to the egg and meat industry since they do not lay eggs and do not fatten up quickly enough to be sold as meat. The practice costs egg producers about $500 million annually, but some European countries including Germany and France have already banned culling of male chicks or plan to phase it out. 

[Release: 6 things to know before deciding to raise backyard chickens.]

If hatcheries could identify the sex of an egg earlier in incubation, billions of male eggs could be humanely killed before the chick can feel pain, as well as reducing waste and environmental impact. The technology that is already on the market for this process called in-ovo sexing depends on either imaging through the shell or sampling the shell through a tiny hole. 

In this new study from researchers at the University of California, Davis and a startup company at the university called Sensit Ventures Inc., it is possible to sniff out the egg’s volatile organic chemicals and determine the egg’s sex. 

The team first had to find out if the chemicals released by male and female embryos give off reliably detectable differences. At study co-author Cristina Davis’s lab at the UC Davis Department of Mechanical and Aerospace Engineering, the team developed sensing chip technology that can collect and analyze organic chemicals in the air.  

They adapted suction cups that are already used for industrial handling of eggs to “sniff” air from the eggs without actually opening them up. Gas chromatography and mass spectrometry analyzed the air samples and the sex of the eggs was confirmed by DNA analysis at the UC Davis Department of Animal Science. 

[Related: Which Came First, The Chicken Or The Egg?]

“We found that there are volatile chemicals from the egg, a scent that you can capture and sort statistically,” study co-author and CEO of Sensit Ventures Tom Turpen said in a statement. 

According to the study, this air-sniffing technique was able to identify male and female embryos at eight days of incubation with 80 percent accuracy, based on two minutes of air sampling. Using this rapid suction-cup sampling method could also be carried out in rows that test multiple eggs at the same time 

“We think that the hardware platform invented at UC Davis could be integrated into hatcheries,” Turpen said.

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About 250 million years ago, massive volcanic eruptions triggered catastrophic climate changes that killed 80 to 90 percent of species on Earth. The Permian-Triassic mass extinction, or the “Great Dying,” paved the way for dinosaurs to dominate Earth, but was even worse than the Cretaceous–Paleogene extinction that wiped out the dinosaurs 65 million years ago. Now, with a new fossil discovery described May 22 in the journal Current Biology, scientists believe that a tiger-sized, saber-toothed creature called Inostrancevia migrated 7,000 miles across Pangea. When it arrived in the southern part of Pangea, Inostrancevia filled a gap in an ecosystem that was devoid of top predators before Inostrancevia too went extinct, as Earth’s species fought to gain a foothold on a changing planet. 

[Related: UV radiation might be behind the planet’s biggest mass extinction.]

Inostrancevia was a gorgonopsian and a saber-toothed predator. It was about the size of a tiger and likely had tough skin similar to a rhinoceros or elephant and looked more like a reptile than most mammals alive today.

“It is equally closely related to all living mammals. Inostrancevia and other gorgonopsians have no direct living descendants. The group went completely extinct in the Permian-Triassic extinction, but distant proto-mammal relatives of gorgonopsians called cynodonts survived the extinction and evolved into mammals in the Triassic Period,” study co-author Christian Kammerer told PopSci. Kammerer is the research curator in Paleontology at the North Carolina Museum of Natural Sciences and research associate at the Field Museum in Chicago.

Previously, scientists had only found Inostrancevia fossils in Russia, but the fossils in this study were found almost 7,000 miles away. A team of researchers led by co-author Jennifer Botha of the GENUS Centre of Excellence in Palaeosciences and the University of the Witwatersrand were digging in South Africa’s fossil-rich Karoo Basin when they unearthed two giant nine to 13-foot-long saber-toothed predators in rocks that date back between 252 and 255 million years.

After reviewing the geographic ranges and ages of the other top predators called the rubidgeine gorgonopsians that were normally found in the area, the team found that these local carnivores went extinct early in the Great Dying. By the time other animals began to go extinct, these apex predators were already gone.

“We did not have a good understanding of when these large predators appeared and went extinct in the African record,” study co-author and Field Museum research scientist Pia Viglietti told PopSci. “This was an important piece in the puzzle to answer because large-bodied predators tend to be at high levels of extinction risk. So, knowing when they went extinct is important for understanding the Great Dying.”

[Related: With bulging eyes and a killer smile, this sabertooth was an absolute nightmare.]

According to the team, these findings demonstrate that fossil-rich locations in South Africa are crucial to better understanding the most catastrophic event in Earth’s history. The team plans to look for more gorgonopsians from more northern parts of Africa and in Europe and to search for earlier records of Northern Hemisphere gorgonopsians moving into the southern part of Pangea.

This peek into the past also bears a warning for our future, since the team says The Great Dying is the historical event that most closely parallels Earth’s current environmental crisis.

“Both involve global warming related to the release of greenhouse gasses, driven by volcanoes in the Permian and human actions currently,” said Kammerer. “[They] represent a very rare case of rapid shifts between icehouse and hothouse Earth. So, the turmoil we observe in late Permian ecosystems, with whole sections of the food web being lost, represents a preview for our world if we don’t change things fast.”

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On May 9, a baby California condor hatched at Liberty Wildlife, a wildlife rehabilitation, education, and conservation organization in Phoenix, Arizona. The hatching is a ray of hope and welcome good news for the struggling species that was only recently brought back from the brink of extinction. 

Only 22 condors were believed to be alive during the 1980s after a maelstrom of habitat loss, poaching, lead poisoning accidents with power lines, and the insecticide DDT. Currently, about 275 wild birds are cruising the skies about California, Utah, Arizona, and Baja California, Mexico, more than 160 are in captivity, and more than 400 live worldwide. 

[Related: Inside the Yurok Tribe’s mission to make critically endangered condors thrive.]

The largest bird species in North America and a crucial part of the ecosystem, California condors are considered sacred to many indigenous peoples. The Yurok Tribe of the Pacific Northwest call California condors “prey-go-neesh,” and say the birds have been tied to the Yurok Hlkelonah, or the cultural and ecological landscape, since the beginning of time. The tribe has officially been a driving force on condor reintroduction since 2008. 

Now, these sacred and important birds face a grave threat in the form of a tiny pathogen. Highly pathogenic avian influenza (H5N1), also called bird flu, is threatening condors at an alarming rate. It was first detected in the California condor in late March, and more than 20 are known to have died since. 

“It is scary particularly for endangered species like the California condors. It has the ability to wipe out an entire species,” Liberty Wildlife’s Animal Care Coordinator Jan Miller tells PopSci. 

One of the birds that succumbed to the disease was the new hatchling’s mother, part of a breeding pair of wild California condors. The mother was found acting suspicious in a cave near the Grand Canyon and was brought to Liberty Wildlife due to suspected bird flu. She died eight days later.  

“Using telemetry, it was assumed that she had laid an egg, probably between March 13 and March 17, and it was predicted to hatch between May 9 and May 17,” Liberty Wildlife’s Executive Director Megan Mosby tells PopSci. “The limited movement of the male led to the assumption that he was trying to incubate an egg.  The biologists at the Arizona Vermilion Cliff site decided that it wasn’t safe for the male, a known breeder, to attempt to raise a chick solo and feed himself, especially in a dank, cool cave … a perfect place for flu contamination.”

[Related: Spy tech and rigged eggs help scientists study the secret lives of animals.]

Biologists brought the egg back to Liberty Wildlife, where it was monitored in a structure called a brooder.  When the egg began to “pip,” the Los Angeles Zoo’s propagation team advised Liberty Wildlife on best practices for monitoring the hatchling’s progress. The team noticed that the chick was in the wrong position in the egg due to where it had pipped, or poked through its membrane, and that it would need assistance in order for the hatch to be successful. 

“Veterinarian Dr. Stephanie Lamb assisted in the freeing of the baby from the egg and the operation was successful.  After a health check, a swab to test for Avian Flu was obtained, and the chick was placed in an incubator with a surrogate (stuffed animal) ‘mother’ condor,” Miller says. 

The hatchling was negative for bird flu and continued to eat solid food and bond with her surrogate plush parent. According to Mosby, the team was excited to find out she was female because 11 of the 21 condors that have died due to bird flu were breeding age females.

On May 17, she was flown to The Peregrine Fund in Boise, Idaho. There she will be raised by foster parents so that she can one day be released back into Arizona’s skies.  

“At this age it is very easy for the chick to imprint on humans so getting her with her own species is critical to her releasability,” says Miller. “The Peregrine Fund has a very advanced propagation department with proven foster parents to help raise chicks for release into the wild. It is a very large operation with proven results.”

According to the team, vultures like the California condor are not only intelligent, but are incredibly necessary to help clean up the environment since they handle dead and decaying animals that can spread disease. 

“Vultures are part of the natural cleanup crew in nature. They deserve every fair chance they can get to continue to survive and be a part of this world,” says Miller. 

In addition to this welcome hatchling’s continued success this week, the United States Department of Agriculture’s Animal and Plant Health Inspection Service approved the emergency use of bird flu vaccine on May 16. The Yurok Tribe called this move, “a huge step in the effort to combat this virulent threat, but still a long road ahead.”

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Humans are born with instincts for crying and smiling, but not for kissing. Sometime in the past, our ancestors had the idea to smack their mouths together and call it romantic. And though we may not know who gave the first smooch, ancient records of these steamy sessions are helping us piece together when people started locking lips. 

The generally accepted earliest evidence we have of making out is religious text written in India in 1500 BCE. And while there was no official word for kissing back then, sentences like “young lord of the house repeatedly licks the young woman” and lovers “setting mouth to mouth” implied more than platonic relationships. But whether this was when kissing all began is still up for debate. In fact, an overlooked collection of written texts from ancient Mesopotamia (modern-day Iraq and Syria) suggests people were kissing further in the past. 

Citing those texts, authors of a new perspective article published today in the journal Science argue romantic kissing occurred 1,000 years earlier than historians first predicted. And as kissing became more of the norm, old medical records reveal the widespread transmission of viruses that spread through lip-to-lip contact.

“Given what we know about the history of kissing in humans and the myriad of similar kissing-like behaviors observed around the animal kingdom, I’m not surprised by these findings,” says Sheril Kirshenbaum, the author of The Science of Kissing, who was not involved in the study. “Whether romantic or not, kissing influences our bodies and brains in so many meaningful ways by guiding our emotions and decisions.”

[Related: Scientists think they found a 2,000-year-old dildo in ancient Roman ruins]

Clay tablets left behind by ancient Mesopotamians in 2500 BCE describe two types of kissing. The first was the friendly-parental kiss. People kissed the feet of their elders or the ground as a sign of respect or submission. 

The second was the lip kiss with a more erotic and intimate overtone. However, there were a few cultural expectations when it came to this type of kissing. Romantic kissing was an action reserved for married couples, as people frowned upon any PDA in Mesopotamia. Kissing among unmarried folks was taboo, considered to be giving in to sexual temptation. People not meant to be sexually active, such as priestesses, were thought to lose their ability to speak if they kissed someone. “The need for such norms indicates that romantic kissing must have been practiced in society at large,” explains lead author Troels Pank Arbøll, an assyriologist (a person studying the language and civilization of ancient Mesopotamia) at the University of Copenhagen.

As more people adopted the practice of kissing on the lips, ancient medical texts described illnesses whose symptoms resemble viral infections spread through mouth-to-mouth contact. The authors note this aligns with DNA analysis from ancient human remains detecting viruses such as herpes simplex virus 1, Epstein-Barr virus, and human parvovirus. All three viruses transmit through saliva.

One example is a disease that the ancient Mesopotamians labeled bu’šānu. The infection involved boils in or around the mouth area. Its name also implies that the infected person might have stunk. While Arbøll says bu’šānu shares several symptoms with herpes, he warns people not to make any assumptions. “As with all ancient disease concepts, they do not match any modern diseases 1:1, and one should be very careful when applying these modern identifications. A disease concept like bu’šānu likely incorporated several modern diseases.”

Mesopotamians likely did not think infectious diseases were spread through kissing, since it is not listed anywhere in the medical texts. However, they had some religiously influenced ideas of contamination, which spurred some measures to avoid spreading the disease. For example, a letter from around 1775 BCE describes a woman in a palace harem with lesions all over her body. Assuming it was contagious, people avoided drinking from any cups she drank, sleeping in her bed, or sitting on her chair.

[Related: When you give octopus MDMA they hug it out]

The findings show that this form of kissing did not originate in a single place. Mesopotamia, India, and other societies separately learned to associate pecks on the lips as romantic. Arbøll says it’s possible other areas also learned about kissing but didn’t have the writing tools to record this behavior. This opens the question of how widely sexual kissing was practiced in the ancient world. 

Some experts are less convinced that kissing was a universal behavior. William Jankowiak, a professor of anthropology at the University of Nevada, Las Vegas, who was not involved in the study, points out that written records of kissing often occurred in complex societies and less so in people living in smaller foraging groups. It’s also difficult to know if romantic kissing was practiced in more than one class or reserved for elite groups in ancient civilizations. Additionally, other factors, such as living in tropical versus colder regions, could influence whether people wanted to lock lips. 

There’s still a long way to go in understanding the ancient history of kissing. But the study does clear up one thing—all the smooching our ancestors did is probably why oral herpes and other kiss-transmitted diseases are a global problem today.

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If Spiderman and Antman took their DNA and mixed it together in a petri dish, the result might be something like the spider species Siler collingwoodi (S. collingwoodi). This tiny, colorful, jumping spider found in China and Japan uses a combination of camouflage and some award-worthy mimicry to deter some hungry predators. In a stressful scenario, these spiders will imitate the way an ant walks to avoid being eaten.

[Related: Black widows battle their even deadlier cousins in a brutal spider war.]

A study published May 17 in the journal iScience found that the combo of camouflage and ant mimicry works to evade spiders that eat other spiders, but not hungry praying mantises. It’s advantageous to mimic an ant because they are typically not very tasty, and can have spiny defenses, chemical repellents, or venom. Not to mention, species of “exploding” ants like Colobopsis saundersi that are not afraid to fight and bite back. While scientists already knew that S. collingwoodi walked like an ant, the team on this study were curious how accurate the mimicry is, whether it imitates multiple species of ants, and how effective it is at discouraging predators. 

“Unlike typical ant-mimicking spiders that mimic the brown or black body color of ants, S. collingwoodi has brilliant body coloration,” co-author and Peking University in China ecologist Hua Zeng said in a statement. “From a human’s perspective, it seems to blend well with plants in its environment, but we wanted to test whether their body coloration served as camouflage to protect against predators.”

To better understand how these ant-inspired theatrics help the spiders avoid becoming dinner, the team collected wild ant-mimicking spiders from four spots in southern Hainan, China, and brought them back to the lab. They also collected another type of jumping spider that does not mimic ants as a comparison and five co-occurring ant species as potential models.  

The team then compared and characterized how the insects and arachnids moved in terms of how they used their individual limbs, their speed, acceleration, and whether they followed a straight path or took a more roundabout way. 

Inside of jumping like most jumping spiders, S. collingwoodi scuttle around like ants. They raise their front legs to mimic an ant’s antennae, bob their abdomens, and lift their legs to walk more ant-like. Out of the five ant species studied, the spider’s style of walking more closely resembled three of the smaller ant species that are closer in size.

“S. collingwoodi is not necessarily a perfect mimic, because its gait and trajectory showed high similarity with multiple ant species,” said Zeng. “Being a general mimic rather than perfectly mimicking one ant species could benefit the spiders by allowing them to expand their range if the ant models occupy different habitats.”

Then it was time to test these defenses against two likely predators. Portia labiata and the praying mantis. Portia labiata is a similarly sized jumping spider with color vision who specializes in preying upon other spiders. The praying mantis is a more generalist predator that has a monochromatic visual system–meaning it has trouble telling multiple colors apart. 

[Related: Jumping spiders might be able to sleep—perchance to dream.]

To see how the color camouflaging was working, they modeled how the two predators would perceive S. collingwoodi relative to the other prey species. They used a background of two plants that the spiders live on—the red-flowering West Indian jasmine and the Fukien tea tree The ant-mimicking spiders were better camouflaged from both predators on the jasmine plant than on the tea tree plant.

The predators were more likely to attack the non-mimicking spider than the ones that imitate ants. Out of 17 trials, the spider launched five attacks—all of them were launched towards a non-mimicking spider. However, praying mantises attacked both prey species with equal readiness.

“We initially thought that both predators would behave similarly in the anti predation experiments, but in fact the simulated ant locomotion of Siler collingwoodi only worked for the jumping spider predator, while the praying mantis showed indiscriminate attacks on both ants and mimics,” co-author and Peking University evolutionary ecologist Wei Zhang said in a statement. 

It is possible that this difference might be driven by each predator’s likelihood of being injured if they eat an ant. The praying mantises are much larger than their prey, and they have a better chance of eating spiny ants without risking catastrophic injury. Predatory spiders do not have this margin for error. 

“For the spider predator, a random attack on an ant could result in injury,” says Zhang, “so they are very careful predators and will only attack if they can distinguish S. collingwoodi from ants with a high degree of certainty.”

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Up until 100 million years ago, butterflies were night creatures. Only nocturnal moths were living on Earth until some rogue moths began to fly during the day. These enterprising members of the order Lepidoptera took advantage of the nectar-rich flowers that had co-evolved with bees by flying during the day. From there, close to 19,000 butterfly species were born.

[Related: Save caterpillars by turning off your outdoor lights.]

In 2019, a large-scale analysis of DNA helped solve the question of when they evolved. Now,  the mystery of where in the world colorful winged insects evolved plagues lepidopterists and museum curators. A study published May 15 in the journal Nature Ecology and Evolution found that butterflies likely evolved in North and Central America, and they forged strong botanical bonds with host plants as they settled around the world.

Getting to this conclusion took a four-dimensional puzzle that makes 3D chess look like a game of Candyland. Scientists from multiple countries had to assemble a massive “butterfly tree of life” using 100 million years of natural history on their distribution and favorite plants, as well as the DNA of more than 2,000 species representing 90 percent of butterfly genera and all butterfly families. 

Within the data were 11 rare butterfly fossils that proved to be crucial pieces to the story.  Butterflies are not common in the fossil record due to their thin wings and very threadlike hair. The 11 in this study were used as calibration and comparison points on the genetic trees, so the team could record timing of key evolutionary events.

They found that butterflies first appeared somewhere in central and western North America. 100 million years ago, North America was bisected by an expansive seaway called the Western Interior Seaway. Present day Mexico was joined in an arc with the United States, Canada, and Russia. North and South America were also separated by a strait of water that butterflies had little difficulty crossing.

The study believes that butterflies took a long way around to Africa, first moving into Asia along the Bering Land Bridge. They then radiated into Southeast Asia, the Middle East, and eventually the Horn of Africa. They were even able to reach India, which was an isolated island separated by miles of open sea at this time. 

[Related: The monarch butterfly is scientifically endangered. So why isn’t it legally protected yet?]

Australia was still connected to Antarctica, one of the last remnants of the supercontinent Pangaea. Butterflies possibly lived in Antarctica when global temperatures were warmer, and made their way north towards Australia before the landmasses broke up. 

Butterflies likely lingered along the western edge of Asia for up to 45 million years before making the journey into Europe. The effects of this pause are still apparent today, according to the authors. 

“Europe doesn’t have many butterfly species compared to other parts of the world, and the ones it does have can often be found elsewhere. Many butterflies in Europe are also found in Siberia and Asia, for example,” study co-author and curator of lepidoptera at the Florida Museum of Natural History Akito Kawahara said in a statement. 

Once butterflies were established all over the world, they rapidly diversified alongside their plant hosts. Nearly all modern butterfly families were on Earth by the time dinosaurs went extinct 66 million years ago. Each butterfly family appears to have had a special affinity for a specific group of plants.

“We looked at this association over an evolutionary timescale, and in pretty much every family of butterflies, bean plants came out to be the ancestral hosts,” Kawahara said. “This was true in the ancestor of all butterflies as well.”

Over time, bean plants have increased their roster of pollinators to include multiple types of bees, flies, hummingbirds, and mammals, while butterflies have similarly expanded their palate. These botanical partnerships helped make butterflies blossom from a minor offshoot of moths to one of the world’s largest groups of insects, according to the study.

“The evolution of butterflies and flowering plants has been inexorably intertwined since the origin of the former, and the close relationship between them has resulted in remarkable diversification events in both lineages,” study co-author and Florida Museum curator Pamela Soltis said in a statement. 

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After an asteroid that wiped out the dinosaurs struck the Earth, the prehistoric giants lost their dominion over the planet. The mammals that rose up about 66 million years ago during the Eocene Epoch had some big shoes to fill—and they certainly grew into the challenge over time.

[Related: We’re one step closer to identifying the first-ever mammals.]

In a study published May 11 in the journal Science, found that a family of extinct rhinoceros-like herbivores called brontotheres began their time on Earth about the size of a dog, but evolved to reach elephant size over a relatively short amount of time. Brontotheres also may have not reached its full size potential before it went extinct roughly 34 million years ago due to changes in their environment.

With the dinosaurs gone at the end of the Cretaceous period (145 million to 66 million years ago), the mammals of the world had significantly less competition for resources, and scientists believe this led to their success as a family. Brontotheres was one of the biggest winners among mammals, and grew from about coyote-sized, 40 pound creatures into 2,000 pound goliaths. According to the study, they did this over a period of only 16 million years, which is very quick in evolutionary terms.

Brontothere means “thunder beasts,” and their powerful name was inspired by Lakota oral histories of violent thunderstorms accompanied by giants, according to the National Park Service.The animals lived in Asia, Europe, and North America. Most species weighed over a ton, but the biggest roamed what is now the South Dakota Badlands. These giants clocked in at about 8 feet tall and 16 feet long. They are the relatives of modern tapirs, horses, and rhinos, and were equipped with Y-shaped horns on their noses. 

The team of researchers on this brontothere size evolution study peered back at the evidence from the family’s fossil record and a family tree of 276 known brontothere individuals. They were fortunate that the fossil record shows most of their evolutionary record, and the team generated computer models to track how the genetic traits of different brontothere species changed. 

They also conducted phylogenetic analysis, or an evaluation of the evolutionary avenues that causes a new species to take shape. This helped them determine how such evolutionary changes may be linked or connected to their increase in body size. 

The data showed that body size actually evolved in both directions across brontothere species. Some would evolve bigger, while other times a species would evolve smaller. They found that the smaller species were more prone to extinction compared to their bigger cousins, and a trend of bulkier brontotheres persisted longer than the smaller species emerged.  

[Related from PopSci+: An ancient era of global warming could hint at our scorching future.]

Towards the end of the Eocene, the remaining brontotheres were true thunder beasts. Their status as megaherbivores likely benefited the beasts, with the smaller animals being more vulnerable to become a carnivore’s dinner. Competition from other big and small herbivores could hardly stand up to the beasts, according to the study.

Unfortunately, at this same time, the climate drastically changed from a more humid herbivore’s paradise to something much more dry. The brontotheres thus lost their evolutionary advantages when the previously lush and green ecosystem dried up. They eventually went extinct about 34 million years ago.

Further research into this family could model the ecological factors like ancient climate shifts that affected how much edible vegetation covered the planet and how it led to the demise of these megaherbivores.

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It’s been just about 20 years since Finding Nemo was released in theaters and the lost “little clownfish from the reef” swam his way into our hearts. However, there is way more to coral reef fish than their beautiful scales and fictional tales. 

[Related: This rainbow reef fish is just as magical as it looks.]

A study published May 11 in the open access journal PLOS Biology found that some of the fish that live in anemones and reefs go through intense physiological changes when they switch from speedy swimming in the open ocean as larvae to settling down to life on the reef.  

Nemo and his young sea turtle pal named Squirt may have had a bit more in common than their age. Like sea turtles, many coral reef fish spawn away from where the animals will eventually settle and live. Adult coral reef fish spawn their larvae in the open ocean and the larvae swim against strong currents to get back to the reef where they will live as adults. Other bottom dwelling marine organisms like sea stars, corals, and urchins also follow this pattern. 

“These first weeks of life can be the most vulnerable for coral reef fishes, and if they don’t make it, that means they cannot grow up to be healthy adults and contribute to coral reef ecosystems,” co-author and James Cook University marine biologist Jodie L. Rummer told PopSci.

All of this swimming demands a lot of energy from the tiny fish, but then once they are settled on the reef floor, they must drastically switch gears and survive in a low-oxygen, or hypoxic, environment at night. 

To learn more about how this adjustment  works, the team collected daily measurements of the cinnamon anemonefish (Amphiprion melanopus) larvae’s swimming speed, oxygen update, and hypoxia tolerance. They observed them in a laboratory setting from the time that they hatched until when they settled down, usually around day nine of life.

“Coral reef fishes, including anemonefishes, as larvae are swimming among the fastest relative to their body size,” study co-author Adam Downie told PopSci. Downie is currently an animal physiologist at the University of Queensland in Australia and conducted the research as part of his PhD at James Cook University. “In our study, maximum speeds were over 12 centimeters [4.7 inches] per second, but for a fish that is the size of your pinky finger nail, that is 10-12 body lengths per second. Comparatively, relative to their size, larval coral reef fishes, including clownfish, outcompete most other marine life in a swimming test and all humans!”

Additionally, they saw that their hypoxia tolerance in the fish increased around day five while their oxygen intake decreased. To investigate how their bodies cope with these lack of oxygen, they sequenced mRNA from larvae of different ages to look for changes in gene activity that occurs during development. These physiological changes were correlated to areas of the gene where hemoglobin are produced and the activity of 2,470 genes changed during development.

[Related: Invasive rats are making some reef fish more peaceful, and that’s bad, actually.]

“These baby fish can change the expression patterns of certain genes that code for oxygen transporting and storage proteins just in time to cope with such low oxygen conditions on the reef,” said Rummer. “These proteins, like hemoglobin and myoglobin, are found in our bodies too and are important in getting oxygen from the environment and delivering it to the muscles, heart, and other organs. Indeed, timing is everything!”

The study found that relative to their body size, cinnamon anemonefish (also called cinnamon clownfish) larvae have the highest oxygen uptake rate of any bony fish currently measured. The genetic changes they can make to take in more oxygen underpin how reef fish can swim at speeds that would make even the most decorated Olympians envious. According to Downie, some studies have clocked clownfish at up to 50 body lengths per second, compared with Michael Phelps’ just under two body lengths per second. 

Since the effects of climate change threatens all marine life, the team believes that warmer ocean temperatures could impair clownfish swimming since the energy demands are so high. The warming waters put reef ecosystems at even more risk, in addition to coral bleaching, ocean acidification, disease, and more. 

“Next steps would be to see how different climate change stressors, such as temperature and pollutants may impact swimming performance of larval clownfishes and their ability to successfully transition from the open ocean to coral reefs,” said Downie. 

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Sadly, vitamins and supplements will not really keep the mosquitoes from biting you this summer, but scientists are still trying to figure out why the insects seem to love sucking some blood more than others.

[Related: How can we control mosquitos? Deactivate their sperm.]

In a small study published May 10 in the journal iScience, a team of researchers looked at the possible effects that soap has on mosquitoes. While some soaps did appear to repel the bugs and others attracted them, the effects varied greatly based on how the soap interacts with an individual’s unique odor profile.

“It’s remarkable that the same individual that is extremely attractive to mosquitoes when they are unwashed can be turned even more attractive to mosquitoes with one soap, and then become repellent or repulsive to mosquitoes with another soap,” co-author and Virginia Tech neuroethologist Clément Vinauger said in a statement.

Soaps and other stink-reducing products have been used for millennia, and while we know that they change our perception of another person’s natural body odor, it is less clear if soap also acts this way for mosquitoes. Since mosquitoes mainly feed on plant nectar and not animal blood alone, using plant-mimicking or plant-derived scents may confuse their decision making on what to feast on next.  

In the study, the team began by characterizing the chemical odors emitted by four human volunteers when unwashed and then after they had washed with four common brands of soap (Dial, Dove, Native, and Simple Truth). The odor profiles of the soaps themselves were also characterized. 

They found that each of the volunteers emitted their own unique odor profile and some of those odor profiles were more attractive to mosquitoes than others. The soap significantly changed the odor profiles, not just by adding some floral fragrances. 

“Everybody smells different, even after the application of soap; your physiological status, the way you live, what you eat, and the places you go all affect the way you smell,” co author and Virginia Tech biologist Chloé Lahondère said in a statement. “And soaps drastically change the way we smell, not only by adding chemicals, but also by causing variations in the emission of compounds that we are already naturally producing.”

The researchers then compared the relative attractiveness of each human volunteer–unwashed and an hour after using the four soaps–to Aedes aegypti mosquitoes. These mosquitoes are known to spread yellow fever, malaria, and Zika among other diseases. After mating, male mosquitoes feed mostly on nectar and females feed exclusively on blood, so the team exclusively tested the attractiveness using adult female mosquitoes who had recently mated. They also took out the effects of exhaled carbon dioxide by using fabrics that had absorbed the human’s odors instead of on the breathing humans themselves.   

[Related from PopSci+: Can a bold new plan to stop mosquitoes catch on?]

They found that soap-washing did impact the mosquitoes’ preferences, but the size and direction of this impact varied between the types of soap and humans. Washing with Dove and Simple Truth increased the attractiveness of some, but not all of the volunteers, and washing with Native soap tended to repel mosquitoes.

“What really matters to the mosquito is not the most abundant chemical, but rather the specific associations and combinations of chemicals, not only from the soap, but also from our personal body odors,” said Vinauger. “All of the soaps contained a chemical called limonene which is a known mosquito repellent, but in spite of that being the main chemical in all four soaps, three out of the four soaps we tested increased mosquitoes’ attraction.”

To look closer at the specific soap ingredients that could be attracting or repelling the insects, they analyzed the chemical compositions of the soaps. They identified four chemicals associated with mosquito attraction and three chemicals associated with repulsion. Two of the mosquito-repellers are a coconut-scented chemical that is a key component in American Bourbon and a floral compound that is used to treat scabies and lice. They combined these chemicals to test attractive and repellent odor blends and this concoction had strong impacts on mosquito preference.

“With these mixtures, we eliminated all the noise in the signal by only including those chemicals that the statistics were telling us are important for attraction or repulsion,” said Vinauger. “I would choose a coconut-scented soap if I wanted to reduce mosquito attraction.”

The team hopes to test these results using more varieties of soap and more people and explore how soap impacts mosquito preference over a longer period of time. 

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When the Human Genome Project launched in 1990, it was hailed as one of the greatest scientific endeavors of all time. The 13-year project identified about 20,000 genes and gave researchers a genetic blueprint to transform modern medicine. Doctors can now use genetic information to better diagnose diseases and debilitating conditions, such as linking a rare case of leg pain to a single mutation. The research also ushered in hope for an age of precision medicine, where every treatment would be tailored to the individual. There was only one problem—the work wasn’t really finished.

That’s because humans are 99.9 percent identical. But the 0.1 percent in genetic differences explains our uniqueness, and can also account for why some people are more susceptible to disease. Having one map of a single genome, which the 90s-era project produced, does not adequately represent the breadth of the human population.

An international study published today in Nature is filling in these gaps by analyzing a much more diverse set of genetic sequences. “We’re retooling the foundation of genomics to create a diverse and inclusive representation of human variation as the fundamental reference structure,” says senior study author Benedict Paten, an associate director at the University of California, Santa Cruz Genomics Institute. 

[Related: The benchmark for human diversity is based on one man’s genome. A new tool could change that.]

By eliminating bias and analyzing more inclusive genomic data, geneticists will have a better understanding of how mutations affect a person’s genes and move us closer to a future with equitable healthcare. 

What is a pangenome?

The research focused on creating a pangenome—a collection of DNA sequences within a single species. Past work focused on a reference genome, built from a few individuals, that was supposed to represent a broader set of genes. A pangenome, on the other hand, is created from multiple people worldwide to more accurately reflect our genetic diversity. 

It’s not as though past geneticists did not want to sequence more genetic variations—they just couldn’t. Erich Jarvis, a genetic professor at Rockefeller University Howard Hughes Medical Institute and a co-author of the study, says technology in the 90s and early 2000s did not allow researchers to see large variations between haplotypes—groups of genes inherited together from a single parent—within and across individuals. 

The focus of a pangenome is to study the genetic differences among individuals from across the world. Jarvis says knowing about genomic variations is important, because some mutations are associated with different traits and diseases. For example, the lipoprotein (a) gene has a complex structure that has not been sequenced in humans. But variations in the gene are known to be associated with an increased risk of heart disease among Black people. By sequencing the entire gene and understanding its variations, doctors may be able to revisit and treat previously unexplained cases of coronary heart disease.

“This paper helps us to understand that DNA [is] more than a sequence of letters; DNA is structurally organized, and human variation that structure is important for genomic function and trait diversity,” says Sarah Fong, a postdoctoral scholar studying human population variation at the University of California, San Francisco who was not involved in the study.

What does the first draft reveal?

The authors collected data on 47 genetically diverse individuals. About half came from Africa, with the others representing four other continents (excluding Australia and Antarctica). The genomic information added information on 119 million base pairs and 1,115 duplications—mutations where a portion of DNA on a gene is repeated. As expected, more than 99 percent of the genetic sequences were similar across individuals. But by including the less than one percent of variations in this new pangenome draft, the authors found that structural changes to genes explained 90 million of the identified base pairs. 

[Related: What we might learn about embryos and evolution from the most complete human genome map yet]

“By moving beyond a single, arbitrary, and linear representation of the genome, the work by the Pangenome Reference Consortium more accurately describes the diversity that exists in our species,” says Rajiv McCoy, an assistant professor of biology at Johns Hopkins University who was not involved in the current study but was recently involved in the first complete sequencing of the human genome.

With the latest pangenome model, it may become easier for geneticists to detect and characterize hard-to-find genetic mutations. When the authors analyzed a separate set of genetic information using the pangenome draft as a reference, they detected 104 percent more structural variants. They also improved the accuracy of the comparison sequence, reducing the  variant error rate by 34 percent.

Still a work in progress

Creating the first draft of the pangenome is only phase one of this two-part project. The second phase will take a couple of years, as the authors build collaborations among other international researchers and perform community outreach in areas where there is less genomic data, such as including members of indigenous cultures.

It might take decades before we see the drafts finalized into a complete picture of the human genome. There are several challenges to address, Fong says, such as the development of an efficient strategy to compare multiple human genomes and a concrete plan for testing for genetic variations in the medical field.

Still, Fong says the benefits will be worth the effort. Having complete, diverse human genomes will advance the way genetics is studied, and create a future where people’s genes are more fully considered when treating diseases.

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Behold the microscopic power of cheese. The dairy product has been a dietary staple for generations, but it is also helping microbiologists better understand nature’s microbiomes. In a study published May 10 in the journal mBio, a team of researchers used cheese rinds to demonstrate how fungal antibiotics can influence how microbiomes develop. 

[Related: Beehives are the honeypot for a city’s microbial secrets.]

Metabolites produced by fungi can improve human health. Some secrete penicillin, which is then purified and used as an antibiotic. For this study, scientists set out to better understand how fungi interact with the microbes living alongside them in microbial communities, with a particular focus on how fungi and bacteria’s relationship.

“My lab is interested in how fungi shape the diversity of microbial communities where they live. Fungi are widespread in many microbial ecosystems, from soils to our own bodies, but we know much less about their diversity and roles in microbiomes compared to more widely studied bacteria,” co-author and Tufts University microbiologist Benjamin Wolfe said in a statement. “To study the ecology of fungi and their interactions with bacteria, we use cheese rinds as a model microbial ecosystem to understand these basic biology questions.

Cheese rinds themselves are microbial communities that form on the surfaces of naturally aged cheeses like brie, taleggio, and some types of cheddar. As the cheeses age, fuzzy and sometimes sticky layers of microbes form on the surfaces of the cheese. The microbes slowly decompose as the cheeses curd and they grow on the surface to create the aromas and colors that give the cheese in the fancy part of the grocery store their more unique properties. 

Wolfe and his team began by investigating a cheesemaker’s problem with mold spreading on the surface of the cheeses and disrupting the normal development of the rind. This causes the cheese to look like the rinds were disappearing as the mold invaded their cheese cave. They collaborated with microbiologist Nancy Keller’s lab at the University of Wisconsin to find out what this mold was doing to the rind microbes and what chemicals the mold may be producing that disrupted the rind. 

They researchers first deleted a gene (laeA) in the Penicillium mold that can control the expression of chemicals that fungi can secrete into their environment. These compounds are called specialized or secondary metabolites. 

“We know that many fungi can produce metabolites that are antibiotics because we have used these as drugs for humans, but we know surprisingly little about how fungal antibiotics work in nature,” said Wolfe. “Do fungi actually use these compounds to kill other microbes? How do these antibiotics produced by fungi affect the development of bacterial communities? We added our normal and our laeA-deleted Penicillium to a community of cheese rind bacteria to see whether deleting laeA caused changes in how the community of bacteria developed.” 

[Related: You might be overusing hand sanitizer.]

When laeA was deleted, most of the antibacterial activity of the Penicillium mold was lost. This discovery helped the team narrow down specific regions of the fungal genome that could produce antibacterial compounds. They narrowed it down to one class of compounds called pseurotins. The metabolites are produced by multiple types of fungi and that can modulate the immune system, kill insects, and inhibit bacteria. 

The study showed that pseurotins can also control how bacterial communities living with that fungi grow and develop. The pseurotins are strongly antibacterial, which means they inhibit some of the bacteria found in artisanal cheeses including Staphylococcus, Brevibacterium, Brachybacterium, and Psychrobacter. This process caused a shift in the cheese rind microbiome’s composition.

It also shows that the antibiotics secreted by fungi can control how microbiomes develop, since the metabolites are in other ecosystems, including the human human microbiome and soil ecosystems. The team expects that these mechanisms of fungal-bacterial interactions are likely very widespread. 

“Our results suggest that some pesky mold species in artisan cheeses may disrupt normal cheese development by deploying antibiotics,” said Wolfe. “These findings allow us to work with cheesemakers to identify which molds are the bad ones and how to manage them in their cheese caves. It also helps us appreciate that every time we eat artisan cheese, we are consuming the metabolites that microbes use to compete and cooperate in communities.”

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The piercing and malevolent gaze of Sauron, the powerful villain The Lord of the Rings, is being honored in a way that may even make Gandalf’s heroic eagles envious. A new genus of butterflies has been named Saurona in honor of one of fiction’s greatest villains.

[Related: Scientists Calculate Calories Needed To Walk To Mordor.]

With their fiery orange hindwings and piercingly dark eyespots, Saurona triangula and Saurona aurigera are the first two species described in this new genus, described in a study published April 10 in the journal Systematic Entomology. Scientists believe that there are more species within this genus waiting to be described.  

“Giving these butterflies an unusual name helps to draw attention to this underappreciated group,” study co-author and Senior Curator of Butterflies at London’s Natural History Museum Blanca Huertas said in a statement. “It shows that, even among a group of very similar-looking species, you can find beauty among the dullness. Naming a genus is not something that happens very often, and it’s even more rare to be able to name two at once. It was a great privilege to do so, and now means that we can start describing new species that we have uncovered as a result of this research.”

Saurona triangula and Saurona aurigera are the first butterflies to be named after the epic villain, but they are not the only animals named after Sauron and other characters from JRR Tolkien’s epic trilogy. A dinosaur (Sauroniops pachytholus) and an insect (Macropsis sauroni), and has also been named after the antagonist and his eye that constantly surveys the lands of Middle Earth. Sauron’s foil and heroic wizard Gandalf also has some animals named for him, including a species of crab, moth, and beetle and a group of fossil mammals. The tragic and troubled creature Gollum has fish, wasps, and fish named after him. 

Naming animals after fictional characters can help draw attention to them in the real world. A recent example comes from the devastating 2019-202 wildfires that struck Australia. The fires burned over 42 million acres and harmed 3 billion animals. Three Australian beetles that were devastated by the fires were named after Pokémon in an effort to attract conservation funding.

The Saurona butterflies are found in the southwestern Amazon rainforest and belong to a butterfly group Euptychiina. This group is difficult to tell apart by their physical characteristics alone, and the scientists on this study used genetic sequencing to help differentiate the new species.

“These butterflies are widely distributed in the tropical lowlands of the Americas, but despite their abundance they weren’t well-studied,” Blanca said. “Historically, the Euptychiina have been overlooked because they tend to be small, brown, and share a similar appearance. This has made them one of the most complex groups of butterflies in the tropics of the Americas.”

[Related: How are dinosaurs named?]

Even with major advances in DNA sequencing like target enrichment and Sanger sequencing that can produce vast amounts of DNA from samples, it took the team over 10 years to assess more than 400 different butterfly species. 

They deciphered the relations between groups and described nine new genera including one called Argenteria. In English, Argenteria translates to “silver mine,” and was named by Blanca and her team due to the silver scales on their wings. Argenteria currently has six species within the genus, but there are likely more out there waiting to be discovered.

The researchers on this study estimate they uncovered up to 20 percent more uncovered species than there were before the project began, and they hope to describe even more. More description will help scientists to better understand the relationships between the different species and the issues they face. 

“It’s important to study groups like the Euptychiina because it reveals that there are many species we didn’t know about, including rare and endemic ones,” said Blanca. “Some of these species are threatened with extinction, and so there’s a lot to do now we can put a name to them. There are also many other butterfly and insect groups that need attention so that they can be better understood and protected.”

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The humble sea star is an ancient marine creature that possibly goes back about 480 million years. They are beloved in touch tanks in aquariums for their celestial shape, spongy skin, and arm suckers. These beautiful five-limbed echinoderms are also helping scientists figure out a crucial life process called tubulogenesis. 

[Related: What’s killing sea stars?]

A study published May 9 in the journal Nature Communications, examined this process of hollow tube formation in sea stars that provides a blueprint for how the organs of other creatures develop.

Tubulogenesis is the formation of various kinds of hollow, tube-like structures. in the body. These tubes eventually form blood vessels, digestive tracts, and even complex organs like the heart, kidneys and mammary glands. It is a basic and crucial process that occurs in the embryo stage, and abnormalities during these processes can cause dysfunctional, displaced, or non-symmetrical organs and even regeneration defects in structures like blood vessel. 

Little is known about the general mechanisms of the hollow tube formation during embryogenesis since animals all use very different strategies to form these tubular structures.

That’s where the sea star comes in. Their process of tubulogenesis is relatively easy to observe since their embryos are very transparent and can be observed without disturbing them. Not to mention, they breed in large numbers year round. This new study reveals the initiation and early stages of tube formation in the sea star Patiria miniata or bat star.

“Most of our organs are tubular, because they need to transport fluids or gasses or food or blood. And more complex organs like the heart start as a tube and then develop different structures. So, tubulogenesis is a very basic step to form all our organs,” study co-author and cell biologist Margherita Perillo of the University of Chicago-affiliated Marine Biological Laboratory said in a statement. 

Not only is the sea star an ideal because of its translucence, the researchers needed an animal that was along the base of the tree of life and evolved before the phylum Chordata– vertebrates including fish, amphibians, reptiles, birds, and mammals, Perillo adds.

Perillo and her colleagues used CRISPR gene editing and other techniques to analyze the gene functions in the sea stars and long time-lapse videos of developing larvae. The team worked out how the sea star generates the tubes that branch out from its gut. From these observations, they could define the basic tools needed for more advanced chordate tubular organs that may have developed. Now, they are getting closer to answering how organisms developed up from one cell into the more complex 3D tubular structures that make up various organisms. 

According to Perillo, in some organisms such as flies, “there is a big round of cell proliferation before all the cells start to make very complex migration patterns to elongate, change their shapes, and become a tube.”

[Related: These urchin-eating sea stars might be helping us reduce carbon levels.]

In other animals, including mammals, cell proliferation and migration occur together. The team found that in sea stars, cells can also proliferate and migrate at the same time in order for the tubes to form the way they do in vertebrate formation. The mechanism behind making organs must have already been established at the base or root of chordate evolution, according to the team. 

Beyond providing evolutionary insights into organ formation, sea stars can also aid in biomedical research. Perillo found that a gene called Six1/2 is a key regulator of the branching process in tube formation. If Six1/2 is taken out of mice, their kidneys form abnormally, but the mice that lack the gene also resist tumor formation, even if they are injected with tumor cells. Understanding this gene, that is overexpressed in cancer cells, may lead to new ways to study disease progression.  

“I can now use this gene to understand not only how our organs develop, but what happens to organs when we have a disease, especially cancer,” said Perillo. “My hope is that, in five to 10 years maximum, we will be able to use this gene to test how organs develop cancer and how cancer becomes metastatic.”

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Before being outbred by Homo sapiens, Neanderthals could have been many things: including the world’s first weavers, artists, and even crab chefs. Their contributions may even go deeper—even to modern day faces. Genetic material from this now extinct crew  influences the shape of human noses today, according to new research. 

In a study published May 8 in the journal Communications Biology, an international team of researchers found a particular gene that leads to a taller nose (top to bottom) might be the product of natural selection when sentient humans adapted to colder climates after leaving the African continent.

[Related: Humans and Neanderthals could have lived together even earlier than we thought.]

“In the last 15 years, since the Neanderthal genome has been sequenced, we have been able to learn that our own ancestors apparently interbred with Neanderthals, leaving us with little bits of their DNA,” Kaustubh Adhikari, a co-author and statistical geneticist at University College London, said in a statement. “Here, we find that some DNA inherited from Neanderthals influences the shape of our faces. This could have been helpful to our ancestors, as it has been passed down for thousands of generations.”

The research team used data from over 6,000 volunteers from Brazil, Colombia, Chile, Mexico, and Peru with mixed European, Native American, and African ancestry. They compared their genetic information to photographs of their faces, and examined the distances between points on the face, like the edge of the lips to the tips of the nose to see how different facial traits might be associated with different genetic markers.

“Most genetic studies of human diversity have investigated the genes of Europeans; our study’s diverse sample of Latin American participants broadens the reach of genetic study findings, helping us to better understand the genetics of all humans,” Andres Ruiz-Linares, co-author and geneticist at University College London, said in a statement.

They found 33 new genome regions that are associated with face shape, and they could replicate 26 of them in comparisons with data from other ethnicities using participants in east Asia, Europe, or Africa.

[Related: Europeans looked down on Neanderthals—until they realized they shared their DNA.]

They looked at a genome region called ATF3, and found that many of those in the study with Native American ancestry had genetic material inherited from Neanderthals that contributes to nasal height. They compared that same genome region with those of east Asian ancestry from a different cohort and saw the same genetic material.  This gene region also has signs of natural selection, suggesting that it has an advantage for those carrying the genetic material.

“It has long been speculated that the shape of our noses is determined by natural selection; as our noses can help us to regulate the temperature and humidity of the air we breathe in, different shaped noses may be better suited to different climates that our ancestors lived in,” Qing Li, a co-author and scientist at China’s Fudan University, said in a statement. “The gene we have identified here may have been inherited from Neanderthals to help humans adapt to colder climates as our ancestors moved out of Africa.”

In 2021, this same team also found that genes influencing facial shapes were inherited from another extinct human species called the Denisovans. In that study, they found 32 gene regions that influence facial features like nose, lip, jaw, and brow shape.

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If humans want to learn more about our higher brain functions and behaviors, some scientists think we should look towards insects—including everything from busy bees to social butterflies  to flies on the wall. A study published May 5 in the journal Science Advances found three diverse, specialized Kenyon cell subtypes in honey bee brains that likely evolved from one single, multi-functional Kenyon cell subtype ancestor.

[Related: Older bees teach younger bees the ‘waggle dance.’]

Kenyon cells (KCs) are a type of neural cell that are found within a part of the insect brain. These cells are  involved in learning and memory, particularly with the sense of smell called the mushroom body. They are found in insects in the large Hymenoptera order from more “primitive” sawflies up to the more sophisticated honey bee. 

“In 2017, we reported that the complexity of Kenyon cell subtypes in mushroom bodies in insect brains increases with the behavioral diversification in Hymenoptera,” co-author and University of Tokyo graduate student said in a statement. “In other words, the more KC subtypes an insect has, the more complex its brain and the behaviors it may exhibit. But we didn’t know how these different subtypes evolved. That was the stimulus for this new study.”

In this study, the team from University of Tokyo and Japan’s National Agriculture and Food Research Organization (NARO) looked at two Hymenoptera species as representatives for different behaviors. The more solitary turnip sawfly has a single KC subtype, compared to the more complex and more social honey bee that has three KC subtypes.

It is believed that the sawfly’s more “primitive” brain may contain some of the ancestral properties of the honey bee brain. To find these potential evolutionary paths, the team used  transcriptome analysis to identify the genetic activity happening in the various KC subtypes and speculate their functions.

[Related: Like the first flying humans, honeybees use linear landmarks to navigate.]

“I was surprised that each of the three KC subtypes in the honey bee showed comparable similarity to the single KC type in the sawfly,” co-author and University of Tokyo biologist Hiroki Kohno said in a statement.  “Based on our initial comparative analysis of several genes, we had previously supposed that additional KC subtypes had been added one by one. However, they appear to have been separated from a multifunctional ancestral type, through functional segregation and specialization.” 

As the number of KC subtypes increased, each one almost equally inherited some distinct properties from a single ancestral KC. The subtypes were then modified in different ways, and the results are the more varied functions seen in the present-day insects.

To see a specific behavioral example of how the ancestral KC functions are present in both the honey bee and the sawfly, they trained the sawflies to partake in a behavior test commonly used in honey bees. The bees, and eventually sawflies, learned to associate an odor stimulus with a reward. Despite initial challenges, the team got the sawflies to engage in this task. 

Then, the team manipulated a gene called CaMKII in sawfly larvae. In honey bees, this gene is associated with forming long-term memory, which is a KC function. After the gene manipulation, the long-term memory was impaired in the larvae when they became adults, a sign that this gene also plays a similar role in sawflies. CaMKII was expressed across the entire single KC subtype in sawflies, but it was preferentially expressed in one KC subtype in honey bees. According to the authors, this suggests that the role of CaMKII in long-term memory was passed down to the specific KC subtype in the honey bee.

Even though insect and mammalian brains are very different in terms of size and complexity, we share some common functions and architecture in our nervous systems. By looking at how insect cells and behavior has evolved, it might provide insights into how our own brains evolved. Next, the team is interested in studying KC types acquired in parallel with social behaviors, such as the honey bee’s infamous “waggle dance.”

“We would like to clarify whether the model presented here is applicable to the evolution of other behaviors,” co-author and University of Tokyo doctoral student Takayoshi Kuwabara said in a statement. “There are many mysteries about the neural basis that controls social behavior, whether in insects, animals or humans. How it has evolved still remains largely unknown. I believe that this study is a pioneering work in this field.”

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Nicknamed the “Earth’s lungs” for its dense oxygen producing forests, the Amazon can absorb 132 billion tons of the planet’s carbon. However, more than 30,000 square miles of the Amazon have been lost since the 1970s. Deforestation, clearing land for agriculture, and climate change fueled wildfires have severely taken its toll on the region, where about 10,000 acres of forest (almost the size of California) has been destroyed every day since 1988. 

However, there is still time to save it—and now scientists may have a “secret weapon” that could not only help reforest the Amazon, but other depleted forests around the world. And it comes from soil deep in the region’s past.

[Related: Brazil’s presidential election is a win for the Amazon—and the planet.]

From roughly 450 BCE and 950 CE, the people living along today’s Amazonia transformed the originally poor soil over many human generations. The soils were enriched with charcoal from low-intensity fires for cooking and burning refuse, animal bones, broken pottery, compost, and manure. The fertile result of these processes is Amazonian dark earth (ADE), or terra preta. The exceptionally fertile black soil is rich in nutrients and stable organic matter derived from charcoal. According to a study published May 5 in the journal Frontiers in Soil Science, it now may help reforest the same area where it was created. 

“Here we show that the use of ADEs can enhance the growth of pasture and trees due  to their high levels of nutrients, as well as to the presence of beneficial bacteria and archaea in the soil microbial community,” co-author Luís Felipe Zagatto, a graduate student at the Center for Nuclear Energy in Agriculture at São Paulo University in Brazil said in a statement. “This means that knowledge of the ‘ingredients’ that make ADEs so very fertile could be applied to help speed up ecological restoration projects.”

The team’s primary aim was to study how ADEs, or ultimately soils with a microbiome that has been artificially composed to imitate them, could boost reforestation. To do this, they conducted controlled experiments in a lab to mimic the ecological succession that happens in the soil when pasture in deforested areas is actively restored to its forest state. 

They sampled ADE from the Caldeirão Experimental Research Station in the Brazilian state of Amazonas. The control soil in the experiments was from the Luiz de Queiróz Superior School of Agriculture in the state of São Paulo. They filled 36 pots with about 6.6 pounds of soil inside a greenhouse with an average temperature of 94ºF to anticipate global warming beyond current average temperatures in Amazonia (between 71 and 82ºF).

One third of the pots only received the control soil, while another third received a 4 to 1 mixture of the control soil and ADE, and the final third has 100 percent ADE. They planted seeds of palisade grass, a common forage for Brazilian livestock, to imitate pasture. The seedlings were allowed to grow for 60 days before the grass was cut so that only the roots remained in the soil. 

Each of the three soils were then replanted with tree seeds of either a colonizing species called Ambay pumpwood, Peltophorum dubium, or with cedro blanco.

[Related: The Amazon is on the brink of a climate change tipping point.]

The seeds were allowed to germinate and then grow for 90 days and then the team measured their height, dry mass, and extension of the roots. They also quantified the changes in the soil’s pH, microbial diversity, texture, and concentration of organic matter–potassium, calcium, magnesium, aluminum, sulfur, boron, copper, iron, and zinc–over the course of the experiment. 

At the beginning, ADEs showed greater amounts of nutrients than control soil, roughly 30 times more phosphorus and three to five times more of each of the other measured nutrients, except manganese. The ADE also had a higher pH and had more sand and silt in it, but less clay. 

Following the experiment, the control soils contained less nutrients than they had at the start, which reflects take-up by the plants. However, the 100 percent ADE soils remained richer than control soils, while nutrient levels were intermediate in the 20 percent ADE soils.

The 20 percent and 100 percent ADE soils also supported a greater biodiversity of both  bacteria and archaea than control soils.

“Microbes transform chemical soil particles into nutrients that can be taken up by plants. Our data showed that ADE contains microorganisms that are better at this transformation of soils, thus providing more resources for plant development,” co-author and University of São Paulo molecular biologist Anderson Santos de Freitas said in a statement.  “For example, ADE soils contained more beneficial taxa of the bacterial families Paenibacillaceae, Planococcaceae, Micromonosporaceae, and Hyphomicroblaceae.”

Additionally, adding ADE to soil improved the growth and development of plants. The dry mass of palisade grass was increased 3.4 times in the 20 percent ADE soil and 8.1 times in 100 percent ADE compared to in control soil. 

These results were enough to convince the team that ADE can boost plant growth, but it does come with some caution. 

“ADE has taken thousands of years to accumulate and would take an equal time to regenerate in nature if used,” co-author and  University of São Paulo molecular biologist Siu Mui Tsai said in a statement. “Our recommendations aren’t to utilize ADE itself, but rather to copy its characteristics, particularly its microorganisms, for use in future ecological restoration projects.”

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This article was original featured on MIT Press.This article is excerpted from Dario Floreano and Nicola Nosengo’s book “Tales From a Robotic World.”

In the early 2010s, a new trend in robotics began to emerge. Engineers started creating robotic versions of salamanders, dragonflies, octopuses, geckos, and clams — an ecosystem of biomimicry so diverse the Economist portrayed it as “Zoobotics.” And yet Italian biologist-turned-engineer Barbara Mazzolai raised eyebrows when she proposed looking beyond animals and building a robot inspired by a totally different biological kingdom: plants. As fluid as the definition of the word robot can be, most people would agree that a robot is a machine that moves. But movement is not what plants are famous for, and so a robotic plant might at first sound, well, boring.

But plants, it turns out, are not static and boring at all; you just have to look for action in the right place and at the right timescale. When looking at the lush vegetation of a tropical forest or marveling at the colors of an English garden, it’s easy to forget that you are actually looking at only half of the plants in front of you. The best-looking parts, maybe, but not necessarily the smartest ones. What we normally see are the reproductive and digestive systems of a plant: the flowers and fruits that spread pollen and seeds and the leaves that extract energy from sunlight. But the nervous system, so to speak, that explores the environment and makes decisions is in fact underground, in the roots.

Roots may be ugly and condemned to live in darkness, but they firmly anchor the plant and constantly collect information from the soil to decide in which direction to grow to find nutrients, avoid salty soil, and prevent interference with the roots of other plants. They may not be the fastest diggers, but they’re the most efficient ones, and they can pierce the ground using only a fraction of the energy that worms, moles, or manufactured drills require. Plant roots are, in other words, a fantastic system for underground exploration — which is what inspired Mazzolai to create a robotic version of them.

“It forced us to rethink everything, from materials to sensing and control of robots.”

Mazzolai’s intellectual path is a case study in interdisciplinarity. Born and raised in Tuscany, in the Pisa area that is one of Italy’s robotic hot spots, she was fascinated early on by the study of all things living, graduating in biology from the University of Pisa and focusing on marine biology. She then became interested in monitoring the health of ecosystems, an interest that led her to get her doctorate in microengineering and eventually to be offered by Paolo Dario, a biorobotics pioneer at Pisa’s Scuola Superiore Sant’Anna, the possibility of opening a new research line on robotic technologies for environmental sensing.

It was there, in Paolo Dario’s group, that the first seeds of her plant-inspired robots were planted. Mazzolai got in touch with a group at the European Space Agency (ESA) in charge of exploring innovative technologies that looked interesting but were still far away from applications, she recalls. While brainstorming with them, she realized space engineers were struggling with a problem that plants brilliantly solved several hundred million years ago.

“In real plants, roots have two functions,” says Mazzolai. “They explore the soil in search of water and nutrients, but even more important, they anchor the plant, which would otherwise collapse and die.” Anchoring happens to be an unsolved problem when designing systems that have to sample and study distant planets or asteroids. In most cases, from the moon to Mars and distant comets and asteroids, the force of gravity is weak. Unlike on Earth, the weight of the spacecraft or rover is not always enough to keep it firmly on the ground, and the only available option is to endow the spacecraft with harpoons, extruding nails, and drills. But these systems become unreliable over time if the soil creeps, provided they work in the first place. They didn’t work for Philae, for example, the robotic lander that arrived at the 67P/Churyumov–Gerasimenko comet in 2014 after a 10-year trip only to fail to anchor at the end of its descent, bouncing away from the ground and collecting just a portion of the planned measurements.

In a brief feasibility study carried out between 2007 and 2008 for ESA, Mazzolai and her team let their imagination run free and described an anchoring system for spacecrafts inspired by plant roots. The research group also included Stefano Mancuso, a Florence-based botanist who would later gain fame for his idea that plants display “intelligent” behavior, although of a completely different sort from that of animals. Mazzolai and her team described an ideal system that would reproduce, and transfer to other planets, the ability of Earth plants to dig through the soil and anchor to it.

In the ESA study, Mazzolai imagined a spacecraft descending on a planet with a really hard landing: The impact would dig a small hole in the planetary surface, inserting a “seed” just deep enough in the soil, not too different from what happens to real seeds. From there, a robotic root would start to grow by pumping water into a series of modular small chambers that would expand and apply pressure on the soil. Even in the best-case scenario, such a system could only dig through loose and fine dust or soil. The root would have to be able to sense the underground environment and turn away from hard bedrock. Mazzolai suggested Mars as the most suitable place in the solar system to experiment with such a system — better than the moon or asteroids because of the Red Planet’s low gravity and atmospheric pressure at surface level (respectively, 1/3 and 1/10 of those found on Earth). Together with a mostly sandy soil, these conditions would make digging easier because the forces that keep soil particles together and compact them are weaker than on Earth.

At the time, ESA did not push forward with the idea of a plant-like planetary explorer. “It was too futuristic,” Mazzolai admits. “It required technology that was not yet there, and in fact still isn’t.” But she thought that others beyond the space sector would find the idea intriguing. After transitioning to the Italian Institute of Technology, in 2012, Mazzolai convinced the European Commission to fund a three-year study that would result in a plant-inspired robot, code-named Plantoid. “It was uncharted territory,” says Mazzolai. “It meant creating a robot without a predefined shape that could grow and move through soil — a robot made of independent units that would self-organize and make decisions collectively. It forced us to rethink everything, from materials to sensing and control of robots.”

The project had two big challenges: on the hardware side, how to create a growing robot, and on the software side, how to enable roots to collect and share information and use it to make collective decisions. Mazzolai and her team tackled hardware first and designed the robot’s roots as flexible, articulated, cylindrical structures with an actuation mechanism that can move their tip in different directions. Instead of the elongation mechanism devised for that initial ESA study, Mazzolai ended up designing an actual growth mechanism, essentially a miniature 3D printer that can continuously add material behind the root’s tip, thus pushing it into the soil.

It works like this. A plastic wire is wrapped around a reel stored in the robot’s central stem and is pulled toward the tip by an electric motor. Inside the tip, another motor forces the wire into a hole heated by a resistor, then pushes it out, heated and sticky, behind the tip, “the only part of the root that always remains itself,” Mazzolai explains. The tip, mounted on a ball bearing, rotates and tilts independent of the rest of the structure, and the filament is forced by metallic plates to coil around it, like the winding of a guitar string. At any given time, the new plastic layer pushes the older layer away from the tip and sticks to it. As it cools down, the plastic becomes solid and creates a rigid tubular structure that stays in place even when further depositions push it above the metallic plates. Imagine winding a rope around a stick and the rope becomes rigid a few seconds after you’ve wound it. You could then push the stick a bit further, wind more rope around it, and build a longer and longer tube with the same short stick as a temporary support. The tip is the only moving part of the robot; the rest of the root only extends downward, gently but relentlessly pushing the tip against the soil.

The upper trunk and branches of the plantoid robot are populated by soft, folding leaves that gently move toward light and humidity. Plantoid leaves cannot yet transform light into energy, but Michael Graetzel, a chemistry professor at EPFL in Lausanne, Switzerland, and one of the world’s most cited scientists, has developed transparent and foldable films filled with synthetic chlorophyll capable of converting and storing electricity from light that one day could be formed into artificial leaves powering plantoid robots. “The fact that the root only applies pressure to the soil from the tip is what makes it fundamentally different from traditional drills, which are very destructive. Roots, on the contrary, look for existing soil fractures to grow into, and only if they find none, they apply just enough pressure to create a fracture themselves,” Mazzolai explains.

This new project may one day result in robot explorators that can work in dark environments with a lot of empty space, such as caves or wells.

The plantoid project has attracted a lot of attention in the robotics community because of the intriguing challenges that it combines — growth, shape shifting, collective intelligence — and because of possible new applications. Environmental monitoring is the most obvious one: The robotic roots could measure changing concentrations of chemicals in the soil, especially toxic ones, or they could prospect for water in arid soils, as well as for oil and gas — even though, by the time this technology is mature, we’d better have lost our dependence on them as energy sources on planet Earth. They could also inspire new medical devices, such as safer endoscopes that move in the body without damaging tissue. But space applications remain on Mazzolai’s radar.

Meanwhile, Mazzolai has started another plant-inspired project, called Growbot. This time the focus is on what happens over the ground, and the inspiration comes from climbing trees. “The invasiveness of climbing plants shows how successful they are from an evolutionary point of view,” she notes. “Instead of building a solid trunk, they use the extra energy for growing and moving faster than other plants. They are very efficient at using clues from the environment to find a place to anchor. They use light, chemical signals, tactile perception. They can sense if their anchoring in the soil is strong enough to support the part of the plant that is above the ground.” Here the idea is to build another growing robot, similar to the plantoid roots, that can overcome void spaces and attach to existing structures. “Whereas plantoids must face friction, grow-bots work against gravity,” she notes. This new project may one day result in robot explorators that can work in dark environments with a lot of empty space, such as caves or wells.

But for all her robots, Mazzolai is still keeping an eye on the visionary idea that started it all: planting and letting them grow on other planets. “It was too early when we first proposed it; we barely knew how to study the problem. Now I hope to start working with space agencies again.” Plant-inspired robots, she says, could not only sample the soil but also release chemicals to make it more fertile — whether on Earth or a terraformed Mars. And in addition to anchoring, she envisions a future where roboplants could be used to grow entire infrastructure from scratch. “As they grow, the roots of plantoids and the branches of a growbot would build a hollow structure that can be filled with cables or liquids,” she explains. This ability to autonomously grow the infrastructure for a functioning site would make a difference when colonizing hostile environments such as Mars, where a forest of plant-inspired robots could analyze the soil and search for water and other chemicals, creating a stable structure complete with water pipes, electrical wiring, and communication cables: the kind of structure astronauts would like to find after a year-long trip to Mars.

Dario Floreano is Director of the Laboratory of Intelligent Systems at the Swiss Federal Institute of Technology Lausanne (EPFL). He is the co-author, with Nicola Nosengo, of “Tales From a Robotic World: How Intelligent Machines Will Shape Our Future,” from which this article is excerpted.

Nicola Nosengo is a science writer and science communicator at EPFL. His work has appeared in Nature, the Economist, Wired, and other publications. He is the Chief Editor of Nature Italy

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A rose by any other name would smell as sweet, as Shakespeare wrote, but erase just one little molecule in their flowers and you’d be lucky to catch a whiff of anything at all. In recent decades, commercial gardeners have bred roses that grow in different colors, are more insect-resistant, and have a longer vase life. But that manipulation has a trade-off: more visually appealing flowers often lose their strong aromatic fragrances. 

What do roses need to make their pleasant odors, and more importantly, how do we get them back? A new study published Monday in PNAS identified a key enzyme called farnesyl diphosphate (FPP) synthase, crucial for driving the reaction that creates a rose’s fresh and floral scent. The findings could help with finding a way to create more mesmerizing and beautiful roses. 

A chemical called geraniol is responsible for the sweet scent we associate with roses. Roses make the compound through a chemical reaction that involves FPP synthase plus several other enzymes. The process involves NUDX1 hydrolase, an enzyme found in the liquid interior of plant cells, or cytosol, that make up the rose petals. To create a strong and sweet aroma, flowers need a ton of NUDX1 hydrolase activity. This is only possible when there is enough of a binding molecule called geranyl diphosphate (GPP). GPP glues to the enzyme and propels it into action. 

[Related: 7 edible flowers and how to use them]

But in order for this process to work, the binding molecule needs to be nearby. This isn’t the case for roses. Senior author Benoît Boachon, a plant biochemist at the French National Centre for Scientific Research, says most plants keep GGP and NUDX1 hydrolase in another area called the plastids. These organelles act as key sites for photosynthesis. This motivated Boachon and his colleagues to figure out where roses get the GPP to make geraniol. He hypothesizes that GPP could have some mechanism transporting it from the plasmid to the cytosol, or there’s another pathway for the flower to generate its own supply of GPP. 

To solve the plant mystery, the study authors studied the biochemical reactions that take place in a variety of pink roses called Old Blush. They isolated different plant parts and shut down chemical pathways involved with the creation or release of geraniol. If the altered roses no longer made geraniol, or the plants produced it in low amounts, that was a major clue to the scientists—they’d found a pathway that plays a role in supplying GPP. On the other hand, the team could rule out a process if geraniol continued to be made at normal levels. 

Their search led them to a particular pathway in plant cytosol–where they took interest in a second, unknown role of the FPP synthase protein. When inhibitors blocked the plant’s ability to express this enzyme, it decreased geraniol levels.  

[Related: How to preserve flowers in 4 easy ways]

The enzyme was found to create two chemical compounds. Plant scientists have known that it makes a chemical related to GPP, called farnesyl diphosphate, which contributes to a rose’s sweet smell. But the study’s biochemical analysis reveals the enzyme is capable of producing GPP as well. Natalia Dudareva, the director of the Center for Plant Biology at Purdue University and one of the coauthors of the study, says that roses must have evolved FPP synthase long ago to produce more readily available GPP. Protein sequencing of the enzyme revealed two amino acids that may have mutated to allow it to produce GPP instead of converting all the GPP to farnesyl diphosphate.

The next step was to see if the FPP synthase enzyme produced similar effects inside a plant in real time. They engineered tobacco leaves to express this enzyme and the chemical pathway used for making geraniol. As they expected, the tobacco leaves where they found the enzyme produced both GPP and farnesyl diphosphate.  

Understanding the essential players involved in fragrance-making could restore the aroma of commercially grown roses. And by isolating the enzyme, Boachon says one potential application is to metabolically reintroduce the sweet fragrance into roses that have lost their iconic smell over time.

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There is truly no shortage of interesting courting and mating rituals throughout the animal kingdom. From trilobites “jousting” to win mates to the important pee sniffing rituals of giraffes, getting it on is serious business. And so is winning over a mate. 

[Related: Male California sea lions have gotten bigger and better at fighting.]

For the first time, scientists have found direct evidence that adult male woolly mammoths experienced an event called musth. Musth comes from the Hindi and Urdu word for intoxicated, and in the case of giant mammals like adult elephants, this is a testosterone-fueled event where the male sex hormone surges and aggression against rival males is heightened. 

The study, published online May 3 in the journal Nature, found evidence that testosterone levels are recorded within the growth layers of both elephant and mammoth tusks. In living male elephants, blood and urine tests recognized the elevated testosterone, but musth battles from its extinct relatives has only been inferred from to fossilized consequences of testosterone-fueled battle, such as pieces of tusk tips and skeletal injuries. 

In the study, an international team of researchers report the presence of annually recurring testosterone surges (up to 10 times higher than baseline levels) are present within a permafrost-preserved woolly mammoth tusk. 

The team sampled tusks from one adult African bull elephant from Botswana and two adult woolly mammoths: a male who roamed Siberia over 33,000 years ago and a roughly 5,597 year-old female that was discovered on Wrangel Island. This Arctic Ocean island used to be connected to northeast Siberia and is the last place where woolly mammoths survived up until about 4,000 years ago. 

“This study establishes dentin as a useful repository for some hormones and sets the stage for further advances in the developing field of paleoendocrinology,” study co-author and paleontologist at the University of Michigan Museum of Paleontology Michael Cherney said in a statement. “In addition to broad applications in zoology and paleontology, tooth-hormone records could support medical, forensic and archaeological studies.”

Hormones are signaling molecules that help regulate physiology and behavior. Testosterone in male vertebrates is part of the steroid group of hormones. Testosterone circulates throughout the bloodstream and accumulates in various tissues.   

[Related: How much acid should you give an elephant? These scientists learned the hard way.]

According the authors, their findings demonstrate that steroid records in teeth can provide scientists with meaningful biological information that can even persist for thousands of years.

“Tusks hold particular promise for reconstructing aspects of mammoth life history because they preserve a record of growth in layers of dentin that form throughout an individual’s life,” study co-author and U-M Museum of Paleontology curator Daniel Fisher said in a statement.  “Because musth is associated with dramatically elevated testosterone in modern elephants, it provides a starting point for assessing the feasibility of using hormones preserved in tusk growth records to investigate temporal changes in endocrine physiology.”

They team used CT scans to find the annual growth increments deep within the tusks, like tree rings. Modern elephant and ancient mammoth tusks are elongated upper incisor teeth, and only hold on to traces of testosterone and other steroid hormones. The chemical compounds are all incorporated into dentin, which is the mineralized tissue that makes up the interior portion of teeth. 

The study also required new methods to extract steroids from the tusk dentin with a mass spectrometer. Mass spectrometers identify chemical substances by sorting the ions present by their mass and charge. 

“We had developed steroid mass spectrometry methods for human blood and saliva samples, and we have used them extensively for clinical research studies. But never in a million years did I imagine that we would be using these techniques to explore ‘paleoendocrinology,'” study co-author and U-M endocrinologist Rich Auchus said in a statement. 

The results and the new measuring technique will likely further new approaches to investigating reproductive endocrinology, life history, and even disease patterns in modern and prehistoric context.

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Researchers at the University of Texas Austin have developed a breakthrough “semantic decoder” that uses artificial intelligence to convert scans of the human brain’s speech activity into paraphrased text. Although still relatively imprecise compared to source texts, the development represents a major step forward for AI’s role in assistive technology—and one that its makers already caution could be misused if not properly regulated.

First published on Monday in Nature Neuroscience, the team’s findings detail a new system that integrates a generative program similar to OpenAI’s GPT-4 and Google Bard alongside existing technology capable of interpreting functional magnetic resonance imaging (fMRI) scans—a device that monitors how and where blood flows to particular areas of the brain. While previous brain-computer interfaces (BCIs) have shown promise in achieving similar translative abilities, the UT Austin’s version is reportedly the first noninvasive version requiring no actual physical implants or wiring.

In the study, researchers asked three test subjects to each spend a total of 16 hours within an fMRI machine listening to audio podcasts. The team meanwhile trained an AI model to create and parse semantic features by analyzing Reddit comments and autobiographical texts. By meshing the two datasets, the AI learned and matched words and phrases associated with scans of the subjects’ brains to create semantic linkages.

After this step, participants were once again asked to lay in an fMRI scanner and listen to new audio that was not part of the original data. The semantic decoder subsequently translated the audio into text via the scans of brain activity, and could even produce similar results as subjects watched silent video clips or imagined their own stories within their heads. While the AI’s transcripts generally offered out-of-place or imprecisely worded answers, the overall output still successfully paraphrased the test subjects’ inner monologues. Sometimes, it even accurately mirrored the audio word choices. As The New York Times explains, the results indicate the UT Austin team’s AI decoder doesn’t merely capture word order, but actual implicit meaning, as well.

[Related: Brain interfaces aren’t nearly as easy as Elon Musk makes them seem.]

While still in its very early stages, researchers hope future, improved versions could provide a powerful new communications tool for individuals who have lost the ability to audibly speak, such as stroke victims or those dealing with ALS. As it stands, fMRI scanners are massive, immovable machines restricted to medical facilities, but the team hopes to investigate how a similar system could work utilizing a functional near-infrared spectroscopy (fNIRS).

There is, however, a major stipulation to the new semantic decoder—a subject must make a concerted, conscious effort to cooperate with the AI program’s goals via staying focused on their objectives. Simply put, a busier brain means a more garbled transcript. Similarly, the decoder tech can also only be trained on a single person at a time. 

Despite these current restrictions, the research team already anticipates the potential for rapid progress alongside misuse. “[F]uture developments might enable decoders to bypass these [privacy] requirements,” the team wrote in its study. “Moreover, even if decoder predictions are inaccurate without subject cooperation, they could be intentionally misinterpreted for malicious purposes… For these and other unforeseen reasons, it is critical to raise awareness of the risks of brain decoding technology and enact policies that protect each person’s mental privacy.”

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The tiny country of Wales on the western coast of Great Britain may now be home to one of the world’s most unexpected fossil sites. Scientists found an “unusually well-preserved”  deposit of over 150 species from 462 million years ago. Interestingly enough, many of them have miniature bodies. The findings by an international team of scientists from the United Kingdom, China, Sweden are detailed in a study published May 1 in the journal Nature Ecology & Evolution.

[Related: These weird marine critters paved the way for the ‘Cambrian explosion’ of species.]

The “marine dwarf world,” as dubbed by the research team, is located in Castle Bank near Llandrindod, central Wales. Two of the study’s authors, Joe Botting and Lucy Muir,  found the site in 2020. Castle Bank is a rare site where the soft tissues and complete organisms are preserved. These specimens help scientists observe how life evolved over time. 

Similar fossil sites like the Burgess Shale fossil deposits in Canada date back 542 to 485 million years ago during the Cambrian period, when recognizable animals first appear in the fossil record. This period is known for a huge explosion of life on Earth. During the Cambrian, the origins of major animal groups still around today, such as mollusks, arthropods, and worms, occurred in what scientists call the Cambrian Explosion. 

The fossilized time capsule from Castle Bank is from the middle of the succeeding Ordovician Period, about 462 million years ago. The Ordovician was a critical time in the history of life when extraordinary diversification of animals occurred and more familiar ecosystems like coral reefs began to appear at the end of the period. Until now, a big gap has existed between thes Cambrian and Ordovician eras. Some of the fauna found at Castle Bank dating back to the middle of this time interval will help fill in evolutionary mysteries about animal shifts over time. 

The more than 150 species found at Castle Bank are almost all new. Many are less than an inch long, but contain tiny details in their bodies. They range from arthropods like crustaceans and horseshoe crabs to worms, sponges, starfish, and more. 

In some animals in the study, internal organs like digestive systems, the limbs of tiny arthropods, delicate filter-feeding tentacles, and even nerves have been preserved. According to the authors, exquisite detail like this is known from Cambrian specimens, but not previously from the Ordovician.

The range of fossils also includes several unusual discoveries, including unexpectedly late examples of animals from the Cambrian that look like the strange looking proto-arthropod opabiniids and slug-like wiwaxiids. Some of the early fossils also resemble modern goose barnacles, possible marine relatives of insects and cephalocarid shrimps, which have no fossil record at all.

[Related: This fossilized ‘ancient animal’ might be a bunch of old seaweed.]

“It coincides with the ‘great Ordovician biodiversification event’, when animals with hard skeletons were evolving rapidly,” Muir, a paleontologist and research fellow from the National Museum Wales, told the BBC. “For the first time, we will be able to see what the rest of the ecosystem was doing as well.”

These findings also have important implications for the evolution of sponges, particularly Hexactinellida. Also called a glass sponge, this animal is considered a transitional interval between sponges that the team have been studying for years. 

“Despite the extraordinary range of fossils already discovered, work has barely begun,” Botting, a paleontologist and research fellow at the National Museum Wales and Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences, told the BBC. “Every time we go back, we find something new, and sometimes it’s something truly extraordinary. There are a lot of unanswered questions, and this site is going to keep producing new discoveries for decades.”

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BUMS. HEINIES. FANNIES. DERRIERES. Few muscles in the human body carry as much cultural clout as the gluteus maximus. “Butts are a bellwether,” writes journalist Heather Radke in her 2022 book Butts: A Backstory. Radke goes on to explain that our feelings about our hindquarters often have more to do with race, gender, and sex than with the actual meat of them. Unlike with a knee or an elbow, Radke argues, when it comes to the tuchus, we’re far more likely to think about form than function—even though it features the largest muscle in the human body. 

For all the scrutiny we spare them (outside of when we’re trying on new jeans) our butts aren’t mere aesthetic flourishes. A booty is, in fact, a unique feat of evolution: Out of any species, humans have the most junk in their trunks. Many other creatures have muscle and fat padding their backsides, and some even have butt cheeks. But none pack anything close to the same proportions as us.

So why did our ancestors develop such a unique cushion? Evolutionary biologists’ best guess is that our shapely rears help us walk upright. The curved pelvic bone that gives the butt its prominence likely developed as our weight moved upward and our muscular needs shifted. Research increasingly suggests that more massive muscles in the vicinity of the buttocks make for faster sprinting and better running endurance too. “The butt is an essential adaptation for the human ability to run steadily, for long distances, and without injury,” Radke writes. 

That said, the gluteus maximus does more than just keep us on our feet. The fat that sits atop it affects how we feel whenever we sit or lie down. The organs nestled behind those cheeks also have a massive influence on our health and wellbeing. Here are a few of the ways our bums factor into scientific understanding, lifesaving medicine, and the future of engineering. 

Digging deep for ancient backsides 

For as long as humans have been making art, they’ve been thinking about bodacious butts. The 30,000-year-old Venus of Willendorf is a famous pocket-size figurine carved by a Western European civilization during the Upper Paleolithic. The statuette, which some archaeologists suspect served as a fertility charm, immortalizes a body too thick to quit.

Scientists also love peeping at the actual posteriors of our early ancestors, which hold a broader archaeological significance in telling the stories of ancient people and their lifestyles. Differences in the pelvis and other sat-upon bones have long been used to determine the sex of unearthed skeletal remains, though we know now there isn’t as clear-cut a binary as researchers long assumed. In 1972, anthropologist Kenneth Weiss flagged that experts were 12 percent more likely to classify skeletons found at dig sites as men versus women, which he blamed on a bias for marking indeterminate skeletons as male. Recent research bears that out, with anthropologists now designating many more remains as having a mix of pelvic characteristics (or simply being inconclusive) than they did historically. Still, while the distinction isn’t completely black and white, the signs of a body primed for or changed by childbirth are useful in figuring out the age and sex of ancient remains. Butt bones can also tell us about how people lived: This March, archaeologists published the oldest known evidence for human horseback riding in the journal Science Advances. They identified their 5,000-year-old equestrians—members of the Yamnaya culture, which spread from Eurasia throughout much of Europe around that same time—with the help of signs of wear and tear to hip sockets, thigh bones, and pelvises. 

Supporting heinies of all shapes and sizes

As Sharon Sonenblum, a principal research scientist at the School of Mechanical Engineering at Georgia Tech, puts it, “What could be better than studying butts?” The Rehabilitation Engineering and Applied Research Lab that she’s part of is perhaps more aptly referred to by its acronym: REAR. 

Stephen Sprigle, a Georgia Tech professor in industrial design, bioengineering, and physiology, started REARLab with better solutions for wheelchair users in mind. A decade ago, he and Sonenblum saw the potential for an engineering-minded solution to the serious clinical problem of injuries from sitting or lying down for extended periods. Pressure sores and ulcers are a risk whenever soft tissue presses against a surface for a prolonged time, and they become more dangerous in hospital settings—where antibiotic-resistant bacteria often lurk—and in people with conditions that hinder wound healing, like diabetes. 

Sonenblum recalls that they set out to answer a deceptively simple question: What makes one backside different from another? To answer it, they had to put a whole lot of booties into an MRI scanner. Those imaging studies and others (including some done on supine patients) have provided an unprecedented amount of data about butt cheeks and the stuff inside them. 

The big headline, Sprigle says, is that “we’re big bags of water. What the skeleton does in that big bag of goo is totally fascinating.” 

The work proved particularly humbling for Sonenblum, who’d intended to spend her career studying how the gluteus maximus affects seating. Instead, she and her colleagues figured out that humans don’t rest on muscle at all—the fat is what really counts. Sonenblum and the rest of the REARLab team are investigating how the natural padding in our rears changes over time, particularly in people who spend a lot of time sitting or supine.

Today, REARLab creates more precise computer models and “phantoms” to help cushion testing—mainly for wheelchair seats, but also for ergonomic chairs of all stripes—better account for real-world bums. Phantoms aren’t quite faux butts; they’re simple and scalable geometric shapes, almost like the convex version of a seat cushion designed for your tuchus to nestle into. They don’t account for bodies’ individual differences either. 

“Phantoms are always a tricky balance between time and representation,” Sonenblum says. “You want to represent the population well, but you can’t have too many or you’ll spend your entire life running tests.”

REARLab’s current approach is to use two shapes—elliptical and trigonometric—to represent a fuller backside and one more likely to pose biomechanical problems when seated, respectively. It would be reasonable to assume the trigonometric butt is the bonier of the two, Sonenblum says, but the reality isn’t so simple. Large individuals with lots of adipose tissue can still lose the round cushioning when they sit. 

“I’ve seen scans of butts that look like this, and when I do, I think, Wow, that’s a high-risk butt,” Sonenblum explains. It comes down to the quality of the tissue, she adds. “If you touch a lot of butts, you’ll find that the tissue changes for people who are at risk [of pressure injuries]. It feels different.”

Sonenblum and Sprigle hope that continued work on backside modeling, cushion-testing standards, and adipose analysis will help wheelchair users and patients confined to their beds for long stretches stay safer and more comfortable. But their work has implications for absolutely anyone who sits down. When asked what folks should take away from their studies, they’re both quick to answer: Move. People with limited mobility may not be able to avoid the loss of structural integrity in their butt tissue, but anyone with the ability to get up often and flex their muscles can keep that natural padding in prime health. 

Finding better bellwethers for bowel cancer

When it comes to protecting your posterior, it’s not just the bodacious bits of the outside that count. One of the biggest backside-related issues scientists are tackling today is the sharp rise in colorectal cancer, which starts with abnormal cell growth in the colon or rectum. It’s already the third most common cancer and second leading cause of cancer death, but it represents a mounting threat, especially for millennials. New cases of young-onset colorectal cancer (yoCRC)—defined as a diagnosis before age 50—have gone up by around 50 percent since the mid-1990s. 

Blake Buchalter, a postdoctoral fellow at Cleveland Clinic Lerner Research Institute focused on cancer epidemiology, says that the most troubling thing about this recent uptick in cases is how little we know about what’s causing it. He and his colleagues suspect that 35- to 49-year-olds who die from colorectal cancer may share many of the same demographics and risk factors—higher body weight, lower activity levels, smoking, alcohol use, and diets high in processed and red meats—seen in patients aged 50 and older. But those under the age of 35 don’t follow those patterns as closely as expected. 

“This indicated to us that mortality among the youngest colorectal cancer patients may have different drivers than among older populations,” Buchalter says. “Our future work in this space aims to identify underlying factors that might be driving higher incidence and mortality among certain age groups in particular geographic regions.” 

Buchalter hopes that more granular data will encourage more granular screening guidelines too. While he was heartened to see the US Preventative Services Task Force shift the recommended colon cancer screening age down from 50 to 45 in 2021, it’s clear that some populations are at risk for the disease earlier, he says. Buchalter and his colleagues hope to zero in on who should be getting screened in their 20s and 30s. 

But colonoscopies, the most commonly recommended form of detection, present a major hurdle in themselves. A 2019 study found that only 60 percent of age-eligible US adults were up to date on their colorectal cancer screenings, with others citing fear, embarrassment, and logistical challenges such as transportation to explain their delayed colonoscopies. At-home fecal tests offer a less invasive alternative, but research shows that fear of a bad diagnosis and disgust with the idea of collecting and mailing samples still keep many folks from using them. Blood tests and colon capsule endoscopy (CCE), in which patients swallow a pill-size camera to allow doctors to examine the gastrointestinal tract, both show promise in supplementing, and perhaps someday replacing, the oft-dreaded colonoscopy.

For now, it’s worth going in for the physical screening if you can manage it. While blood and stool tests can accurately detect signs of the cancer, colonoscopies can actually help prevent it. During a standard colonoscopy, gastro­enterologists are able to identify and remove potentially precancerous polyps known as adenomas on the spot. No DIY kit can manage that.  

Tracking microbiomes with futuristic commodes

Meanwhile, other researchers are uncovering health secrets from long-ago water closets. In 2022, archaeologists uncovered what they believe to be the oldest flush toilet ever found, in Xi’an, China. The 2,400-year-old lavatory features a pipe leading to an outdoor pit. Researchers believe the commode, which was located inside a palace, allowed servants to wash waste out of sight with buckets of water. Flush toilets wouldn’t appear in Europe until the 1500s, and wouldn’t become commonplace until the late 19th century. Up until that point, major US cities employed fleets of “night soil men” to dig up and dispose of the contents of household privies and public loos.

As far as we’ve come from the days of night soil, the future of the humble toilet looks even brighter. Sonia Grego, an associate research professor in the Duke University Department of Electrical and Computer Engineering, says she’s “super-excited” to see commodes enter the 21st century. 

“Smart” toilets boast everything from app-controlled heated seats to detailed water-usage trackers, and could grow into a $13.5 billion industry by the end of the decade. But Grego’s team—the Duke Smart Toilet Lab at the Pratt School of Engineering—is focused on turning waste flushed down porcelain bowls into a noninvasive health tool. She envisions a future in which your toilet can warn you of impending flare-ups of gut conditions like irritable bowel syndrome, flag dietary deficiencies, and even screen for signs of cancer. 

“When we first started to work on the smart toilet for stool analysis, laboratory scientists were skeptical that accurate analytical results could be obtained from specimens that had been dropped in a toilet instead of a sterile collection container,” Grego recalls. “The perspective is very different now.”

Drawing inspiration from wild butts 

Humans may be unusually blessed in the butt-cheek department, but that doesn’t mean other animals’ rears hold less scientific appeal. From modeling the evolution of the anus to cracking the code on climate-friendly gut microbes, scientists are keeping close tabs on all sorts of animal bottoms. Some researchers are even hoping to harness the power of butt breathing—yes, actually breathing through your butt—for future applications in human medicine. 

We’ll circle back to backside breathing in a moment. First, let’s consider the wombat. While it’s true enough that everybody poops, these marsupials are the only animals known to drop cubes. For years, no one was quite sure how they managed to get a square peg out of a round hole. Some even assumed the wombat must have an anus designed for squeezing out blocks instead of cylinders. In 2020, mechanical engineers and wildlife ecologists at Georgia Tech teamed up to publish a surprising new explanation for the shape in the aptly named journal Soft Matter. They’d borrowed roadkill from Australia to do the first-ever close examination of a wombat’s intestines. By inflating the digestive tract and comparing it to more familiar pig intestines, they were able to show that the marsupial’s innards have more variation in elasticity: Instead of being fairly uniform throughout, the organs have some inflexible zones. The team’s findings suggest that a few nooks within the digestive system—some stretchy, others stiff—provide a means to shape the refuse into a square. 

Wombat butts themselves, by the by, are veritable buns of steel. Their rumps contain four fused bony plates surrounded by cartilage and fat and can be used to effectively plug up the entrance to a burrow when potential predators come sniffing around. While this has yet to be caught happening live, some scientists think wombats can even use their powerful bums to crush the skulls of intruders like foxes and dingoes who manage to make it inside. 

So now we have more clarity on how wombats poop cubes, but the question of why remains unanswered. Experts have posited that wombats communicate with one another by sniffing out the location of poop cubes, making it advantageous to produce turds less likely to roll out of place. Others argue that the unusual shape is a happy accident: Wombats can spend as long as a week digesting a single meal, with their intestines painstakingly squeezing out every possible drop of moisture to help them survive the arid conditions Down Under. Their entrails, when unwound, stretch some 33 feet—10 feet more than typical human guts—to help facilitate the frugal squeezing. When the species is raised in captivity with loads of food and water, their poops come out moister and rounder. 

Elsewhere in the world of scat science, folks are working to understand the secrets of nonhuman gut microbiomes. Earlier this year, biotechnologists at Washington State University showed that baby kangaroo feces could help make beef more eco-friendly. Joey guts contain microbes that produce acetic acid instead of methane, which cows burp out in such abundance that it significantly worsens climate change. By reseeding a simulated cow stomach with poop from a newborn kangaroo, researchers say they successfully converted the gut to a factory of acetic acid, which doesn’t trap heat in the atmosphere. They hope to try the transfer out in a real bovine sometime soon. 

Going back to the butt breathing, scientists are hoping to suss out how to give humans a superpower already exhibited by catfish and sea cucumbers. In 2021, Japanese researchers reported in the journal Med that they’d been able to keep rodents alive in oxygen-poor conditions by ventilating them through their anuses. Inspired by loaches—freshwater fish that can take in oxygen through their intestines—the scientists are trying to find new ways to help patients who can’t get enough air on their own. They’ve moved on to study pigs, which they say do wonderfully with a shot of perfluorodecalin (a liquid chemical that can carry large amounts of oxygen) up the bum. 

From an evolutionary standpoint, it’s not all that surprising that our outbox can handle the same duties as our inbox. Though it’s still not clear which came first, it’s well established that the anus and the mouth develop out of the same rudimentary cell structures wherever they appear. Some of the most basic animals still use a single opening for all their digestive needs. And one creature—just one, as far as we know—has a “transient anus.”

In 2019, Sidney Tamm of the Marine Biological Laboratory in Woods Hole, Massachusetts, demonstrated that the warty comb jelly creates new anuses as needed. Whenever sufficient waste builds up—which happens as often as every 10 minutes in young jellies—the gut bulges out enough to fuse with the creature’s epidermis, creating an opening for defecation. Then it closes right back up. It’s possible that the world’s first anuses followed the same on-demand model, proving yet again that the butt and its contents are worthy of our awe, curiosity, and respect.  

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It’s hard to imagine life without the nightshade family. It includes the likes of tomatoes, potatoes, peppers, and eggplants—some of the essential ingredients for a healthy diet–and delicious recipes. But, it turns out one of these tasty flowering plants has a longer history in North America than scientists previously believed. 

According to a March paper in the journal New Phytologist, the chili pepper may have been growing roots in present-day Colorado at least 50 million years ago—quite a bit earlier than scientists originally believed.  Previously, the chili pepper’s origin was placed 15 million years ago in South America. The newest theory emerged when a postdoc and an undergraduate student at University of Colorado-Boulder discovered a fossil of a plant that uncannily resembles the chili pepper, notably through its spiky ends on a fruiting stem called the calyx. 

“The world has maybe 300,000 plant species. The only plants with that kind of calyx is this group of 80 or 90 species,” Stacey Smith, senior author of the paper and associate professor of evolutionary biology at CU Boulder, said in a press release.

[Related: 5 heirloom foods that farmers want to bring back from obscurity.]

The well-preserved specimen was revealed in the Green River Formation, a site chock full of Eocene fossils and discoveries. But, it ended up not being as rare as the authors thought at first—two more similar chili pepper deposits from Green River were hidden in the CU Boulder collections and another at the Denver Museum of Nature and Science. These fossils were uncovered in the 1990s, but it certainly isn’t unheard of for discoveries to lay in wait until the right scientists come along. 

The Green River Formation is a marvel for capturing the Eocene, which lasted from around 34 to 56 million years ago and marked the beginning of the era of mammals. During this epoch, the amount of carbon in the atmosphere was around double that of today, paving the way for palm trees to grow in Alaska and a lack of ice driving sea levels 500 feet higher than they are currently. 

So what could’ve happened that caused the gap between when chili peppers were evolving in Colorado and when they appeared in South America during the Miocene? The authors theorize that modern birds, which have been able to fly long distances for some 60 million years, could’ve carried seeds and plants in their poop or stuck to their bodies. 

Through birds, chili peppers would’ve made their way to South America. Since the latest discovery puts the evolution of chili peppers back to the days of Gondwana, transoceanic travel may have been unnecessary. Birds could simply fly across shorter watery distances or via a chain of volcanic islands, the scientists wrote in the new paper. 

[Related: Oldest evidence of digested plants in a roughly 575-million-year-old creature’s gut.]

Nevertheless, this discovery puts the oldest chili peppers in a place that no longer has many native nightshades or any chili peppers at all. “These chili peppers, a species that we thought arose in an evolutionary blink of an eye, have been around for a super long time,” Smith added. “We’re still coming to grips with this new timeline.”

So next time you break out a meal of Colorado-style chili, that bowl of goodness might have even more local roots that anyone realized.

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This article originally appeared in Knowable Magazine.

From the brightly colored poison frogs of South America to the prehistoric-looking newts of the Western US, the world is filled with beautiful, deadly amphibians. Just a few milligrams of the newt’s tetrodotoxin can be fatal, and some of those frogs make the most potent poisons found in nature.

In recent years, scientists have become increasingly interested in studying poisonous amphibians and are starting to unravel the mysteries they hold. How is it, for example, that the animals don’t poison themselves along with their would-be predators? And how exactly do the ones that ingest toxins in order to make themselves poisonous move those toxins from their stomachs to their skin?

Even the source of the poison is sometimes unclear. While some amphibians get their toxins from their diet, and many poisonous organisms get theirs from symbiotic bacteria living on their skin, still others may or may not make the toxins themselves — which has led scientists to rethink some classic hypotheses.

Deadly defenses

Over the long arc of evolution, animals have often turned to poisons as a means of defense. Unlike venoms — which are injected via fang, stinger, barb, or some other specialized structure for offensive or defensive purposes — poisons are generally defensive toxins a creature makes that must be ingested or absorbed before they take effect.

Amphibians tend to store their poisons in or on their skin, presumably to increase the likelihood that a potential predator is deterred or incapacitated before it can eat or grievously wound them. Many of their most powerful toxins — like tetrodotoxin, epibatidine and the bufotoxins originally found in toads — are poisons that interfere with proteins in cells, or mimic key signaling molecules, thus disrupting normal function.

That makes them highly effective deterrents against a wide range of predators, but it comes with a problem: The poisonous animals also have those susceptible proteins — so why don’t they get poisoned too?

It’s a question that evolutionary biologist Rebecca Tarvin took up when she was a graduate student at the University of Texas at Austin. Tarvin opted to study epibatidine, one of the most potent poisons of the thousand-plus known poison frog compounds. It’s found in frogs such as Anthony’s poison arrow frog (Epipedobates anthonyi), a small, ruddy creature with light-greenish-white splotches and stripes. Epibatidine binds to and activates a receptor for a nerve-signaling molecule called acetylcholine. This improper activation can cause seizures, paralysis and, eventually, death.

Tarvin hypothesized that the frogs, like some other poisonous animals, had evolved resistance to the toxin. She and her colleagues identified mutations in the genes for the acetylcholine receptor in three groups of poison frogs, then compared the activity of the receptor with and without the mutation in frog eggs. The mutations slightly changed the receptor’s shape, the team found, making epibatidine bind less effectively and limiting its neurotoxic effects.

That helps to solve one problem, but it presents another: The mutations would also prevent acetylcholine itself from binding effectively, which would disrupt normal nervous system functions. To address this second problem, Tarvin found, the three groups of frogs each have another mutation in the receptor protein that again changes the receptor’s shape in a way that allows acetylcholine to bind but still rejects epibatidine. “This is a series of very slight tweaks,” Tarvin says, which make the receptor less sensitive to epibatidine while still allowing acetylcholine to perform its usual neural duties.

Tarvin, now at the University of California, Berkeley, is researching how animals evolve to cope with toxins, using a more tractable experimental organism, the fruit fly. To that end, she and her colleagues fed food containing toxic nicotine to two lineages of fruit flies that differed in their ability to break down nicotine.

When the researchers exposed fly larvae to predators — parasitic wasps that laid eggs in the flies — both groups of flies were protected by the nicotine they ate, which killed off some of the developing parasites. But only the faster-metabolizing flies benefited from their toxic diet, because the slower-metabolizing flies suffered more from nicotine poisoning themselves.

Tarvin and her students are now working on an experiment to see if they can induce the evolution of adaptations, such as those she identified in the frogs’ proteins, by exposing generations of flies to nicotine and wasps, then breeding the flies that survive.

Fishing for poisons

Poisonous animals must do more than survive their own toxins; many of them also need a way to safely transport them in their bodies to where they’re needed for protection. Poison frogs, for instance — which obtain their toxins from certain ants and mites in their diet — must ship the toxins from their gut to skin glands.

Aurora Alvarez-Buylla, a biology PhD student at Stanford University, has been trying to nail down which genes and proteins the frogs use for this shipping. To do so, Alvarez-Buylla and her colleagues used a small molecule she describes as a “fishing hook” to catch proteins that bind to a toxin — pumiliotoxin — that the frogs ingest. One end of the hook is shaped like pumiliotoxin, while the other end bears a fluorescent dye. When a protein that would normally bind to pumiliotoxin instead latches onto the similar hook, the dye allows the researchers to identify the protein.

Alvarez-Buylla expected her hook to catch proteins similar to saxiphilin, which is thought to play a role in transporting toxins in frogs, or other proteins that transport vitamins. (Vitamins, like toxins, are usually scavenged from the diet and then moved around the body.) Instead, she and her fellow researchers found a new protein, similar to a human protein that transports the hormone cortisol. This new transporter, they found, can bind to multiple different toxic alkaloids found in different species of poison frogs. The similarity suggests that the frogs have borrowed the hormone-transporting system to also transport toxins, says Lauren O’Connell, Alvarez-Buylla’s PhD advisor at Stanford and a coauthor of the paper, which is still to be formally peer-reviewed.

This may explain why the frogs aren’t poisoned by the toxins, O’Connell says. Hormones often become active only when an enzyme cleaves their carrier, releasing the hormone into the bloodstream. Similarly, the new protein may bind to pumiliotoxin and other toxins and prevent them from coming into contact with parts of the frog nervous system where they could cause harm. Only when the toxins reach the right spot in the frogs’ skin would the toxin-carrying protein release them, into skin glands where they can be safely stored.

In future work, the scientists aim to understand exactly how the new protein can bind to several different types of toxins. Other known toxin-binding proteins, like saxiphilin, tend to bind tightly to just a single toxin. “What’s special about this protein is that it’s a little bit promiscuous in who it binds to, but also there’s some selectivity there,” says O’Connell. “How does that work?”

Turning toxic

While poison frogs definitively get their toxins from the food they eat, the source of toxins used by other poisonous amphibians is not always clear-cut. Amphibians such as toads, it appears, may make their own poisons.

To show this, TJ Firneno, an evolutionary biologist at the University of Denver, and his colleagues manually emptied the toxin glands of 10 species of toads by squeezing the glands (“It’s like popping a zit,” Firneno says, and is harmless to the toads), then looked at which genes were most active in those glands 48 hours later. The hypothesis, says Firneno, was that genes especially active after the glands are emptied could be involved in toxin synthesis.

Firneno and his colleagues identified several activated genes that are known to be part of metabolic pathways for creating molecules related to toxins in plants and insects. The genes they identified, Firneno says, can help point scientists in the right direction for further investigations into how toads may make their toxins.

Other amphibians may rely on symbiotic bacteria for their toxins. In the United States, newts of the genus Taricha are among the country’s most toxic animals. Though they look harmless, individual newts from some populations of these ancient creatures contain enough tetrodotoxin to kill numerous people. Many scientists believed the newts made the toxin themselves. But when a team of researchers collected bacteria from the newts’ skin, then cultured individual microbial strains, they found four types of tetrodotoxin-producing bacteria on the amphibians’ skin. That’s similar to other tetrodotoxin-containing species, such as crabs and sea urchins, where scientists agree that bacteria are the source of the toxin.

The origin of the toxin in these newts has broader ramifications, because they — and the garter snakes that eat them — are poster animals for what has been considered a classic example of coevolution. The snakes’ ability to eat the highly toxic newts is evidence that they have coevolved with the newts, gaining resistance so that they can continue to eat them, some scientists think. Meanwhile, the newts, the idea goes, have been evolving ever-greater toxicity to try and keep the snakes at bay. Scientists refer to this kind of escalating competition as an evolutionary arms race.

But in order for the newts to participate in such an arms race, they have to have genetic control of the amount of toxin they produce so that natural selection can act, says Gary Bucciarelli, an ecologist and evolutionary biologist at the University of California, Davis, who coauthored a re-evaluation of the arms race idea in the 2022 Annual Review of Animal Biosciences. If the tetrodotoxin actually comes from bacteria on the newts’ skin, it’s harder to see how the newts could turn up the toxicity. The newts could conceivably coerce the bacteria to pump out more tetrodotoxin, Bucciarelli says, but there’s no evidence that this happens. “It’s certainly not this very tightly linked, antagonistic relationship between newts and garter snakes,” he says.

Indeed, at the field sites where Bucciarelli works in California, he’s never actually witnessed a garter snake eating a newt. “If you follow the literature, you’d think that there are snakes just picking off newts like crazy at the edge of a stream or a pond. You just don’t see that,” he says. Instead, the snakes’ resistance to tetrodotoxin could have arisen for some other reason, or even by evolutionary happenstance, he says.

The newts’ toxin source is far from nailed down, though. “Just because you have bacteria that do something that live on your skin, doesn’t mean that’s the source in newts,” says biologist Edmund Brodie III, who was among the scientists that first put forward the arms race hypothesis between the snakes and newts more than 30 years ago. Brodie notes that other researchers have found that newts contain molecules that, based on their structures, may be part of a biological pathway for newts to synthesize their own tetrodotoxin. Still, Brodie says of the study showing that bacteria found on the newts can produce tetrodotoxin, “it’s the best thing we have so far.”

Brodie’s instinct is that one way or the other, the newts control their tetrodotoxin production, whether that’s by making the tetrodotoxin themselves or somehow manipulating their bacteria. The presence of bacteria as a third player in the newt-snake war would just make it an even more interesting system, he says.

One major barrier in determining whether the newts can make tetrodotoxin on their own is that no full genome has been published for Taricha newts. “They have one of the largest genomes of any animal we know of,” says Brodie.

Studying the ways that poison animals adapt and use toxins, just like much basic science research, has inherent interest for researchers who seek to understand the world around us. But as climate change and habitat destruction contribute to an ongoing loss of biodiversity that has hit amphibians especially hard, we’re losing species that not only have intrinsic importance as unique organisms but are also sources of potentially lifesaving and life-improving medicines, says Tarvin.

Epibatidine, tetrodotoxin and related compounds, for example, have been investigated as potential non-opioid painkillers when administered in tiny, controlled doses.

“We’re losing these chemicals,” Tarvin says. “You could call them endangered chemical diversity.”

This article originally appeared in Knowable Magazine, an independent journalistic endeavor from Annual Reviews. Sign up for the newsletter.

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Beer is more than one of humanity’s most beloved beverages—it’s also one of its oldest. Recent archaeological discoveries date it back 13,000 years ago in the eastern Mediterranean. It was once considered so sacred that only women could brew it–until witchcraft accusations stopped that in its tracks. 

[Related: Ancient poop proves that humans have always loved beer and cheese.]

The origins of our favorite types of beers are also starting to come into focus with a fun combination of history and science. A study published April 27 in the journal FEMS Yeast Research reveals a possible origin story for lager beer, a light type of beer produced by bottom-fermenting yeast. It can be pale, dark, or amber in color and pairs well with shellfish, grilled pork, and spicy foods among others.

The research team used historical records, in tandem with evolution and genomics research, and believe that lager likely originated at the court brewery–or Hofbräuhaus–of Maximilian I, the elector of Bavaria.

Lager surpassed ale as the most common beer produced around the turn of the 20th century and over 150 billion liters of lager beer are sold annually around the world. However, the shift from ale to lager started centuries before when a new yeast species Saccharomyces pastorianus or “lager yeast,” popped up in Germany around the end of the Middle Ages. The new yeast was a hybrid species that was the product of mating of top-fermenting ale yeast Saccharomyces cerevisiae and the cold-tolerant Saccharomyces eubayanus around the beginning of the 17th century. 

“Lager is a beer brewed at low temperatures using yeast that are described as bottom-fermenting,” study author and University of Cork microbiologist John Morrissey wrote in The Conversation. “Yeast are single-celled fungi used in brewing to convert maltose to alcohol and carbon dioxide, giving beer its booziness and fizz. They are either top- or bottom-fermenting.”

S. pastorianus is a bottom-fermenting lager yeast, and its origins have been “shrouded in mystery and controversy,” according to Morrissey. The assumption was that the hybrid yeast arose when traditional ale fermentation became contaminated with wild yeasts. However, the team on this study doubted this historic assumption, and used detailed analysis of Central European historical brewing records to dig in more. They discovered that “lager-style” bottom fermentation was actually happening in Bavaria 200 years before the hybrid S. pastorianus yeast was born.

The team believes that it was actually the top-fermenting ale yeast S. cerevisiae that contaminated a batch of beer brewed with the cold-tolerant S. eubayanus. They believe that the source of the contaminating yeast was a wheat brewery in the small Bavarian town of Schwarzach.

[Related: The key to tastier beer might be mutant yeast—with notes of banana.]

“Bottom fermentation originated in northern Bavaria. Not only was it common practice in this part of Germany, but the Bavarian Reinheitsgebot brewing regulations of 1516 only permitted bottom fermentation. Thus, from at least the 16th century onwards, Bavarian brown beer was produced by mixtures of different bottom-fermenting yeast species known as stellhefen,” wrote Morrissey.

However, in neighboring Bohemia, excellent wheat beer made with S. cerevisiae was made in huge quantities and imported into Bavaria. To limit the blow to the economy from these imports, Bavarian ruler Wilhelm IV gave Baron Hans VI von Degenberg a special privilege to brew and sell wheat beer in the border regions to Bohemia in 1548.

Maximilian I eventually took power in 1602, and he seized the wheat beer privilege himself and took over the von Degenbergs’ Schwarzach breweries. The team believes that it was in October 1602 that the yeast from the wheat brewery was brought to the court brewery in Munich where the hybridization took place and lager yeast S. pastorianus was born.

“This theory is consistent with published genetic evidence showing that the S. cerevisiae parent of S. pastorianus was closer to ones used to brew wheat beer than strains used for barley-based ale,” wrote Morrissey.

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In response to climate change, a lot of animals—such as polar bears and birds like sparrows—appear to be getting smaller in size. However, male California sea lions have increased their average body size even as their population has grown and the competition for food and resources has increased. 

In a study published April 27 in the journal Current Biology found that sex selection was a strong driving force for the male sea lions to strengthen the neck and jaw muscles that they use to fight for mate and to grow larger. Additionally, both male and female sea lions responded to food shortages by diversifying their diets and foraging further from the shore in some cases.

[Related: Fish populations thrive near marine protected areas—and so do fishers.]

Numerous marine species have rebounded a bit since the Marine Mammal Protection Act was passed in 1972, but California sea lions are notable for the size and duration of their population increase. The number of breeding females have tripled since the 1970s and the population growth is only beginning to plateau now. 

“Body size reduction is not the universal response to population increase in marine predators,” co-author and University of California Santa Cruz and the Smithsonian Institution paleoecologist  Ana Valenzuela-Toro said in a statement. “California sea lions were very resilient over the decades that we sampled and were able to overcome increasing competition thanks to prey availability. They’re like the raccoons of the sea: they can consume almost everything, and they can compensate if something is lacking.”

In the study, the team analyzed museum specimens of adult male and female California sea lions that were collected between 1962 and 2008. To estimate changes in body size, they then compared the overall size of over 300 sea lion skulls, taking into account other skull features like the size of muscle attachment points, to assess the changes made in both neck flexibility and biting force.

To get an idea of where the sea lions were foraging and what they were eating, the team took tiny bone samples from the skulls and measured their stable carbon and nitrogen isotope composition. “Carbon provides information about habitat use—whether they’re foraging along the coast or offshore—and nitrogen provides insights about the trophic level of their prey, for example if they’re consuming smaller or larger fish,” said Valenzuela-Toro.

The team found that overall the male sea lions have increased in size, while females have remained stable. They believe that the sex difference is likely due to the fact that size matters more for a male in terms of mating success. “One male can breed with many females, and males in the breeding colony fight with each other to establish their territory,” said Valenzuela-Toro. “Bigger males are more competitive during physical fights, and they can go longer without eating, so they can stay and defend their territory for longer.”

[Related: For marine life to survive, we must cut carbon emissions.]

The male sea lions also increased their biting force and neck flexibility over this same time period. This allows them to move their heads more with greater agility and bite harder when fighting other males. 

The isotopic analyses showed that both sexes managed to meet nutritional needs through diet diversification and going further north for food. Female sea lions consistently had a more diverse diet than the male sea lions, and the authors suggest that this flexibility in food choice may be what allowed females to maintain average body size. 

The flexibility can only take sea lions so far, however, and climate change is putting their future in jeopardy. The dynamics that allowed for this growth occurred when their prey of sardines and anchovies were plentiful, and the populations of both fish have collapsed in recent years. The California sea lions have continued to diversify their diets to compensate, but are struggling. 

“As climate change progresses, prey availability of sardines and anchovies will decrease even more, and eventually we will have more permanent El Niño-like warming conditions, reducing the size and causing a poleward shift of these and other pelagic fishes,” said Valenzuela-Toro “It will be a really hostile environment for California sea lions, and eventually we expect that their population size will stop growing and actually decline.”

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For nearly a century, Balto the sled dog has been celebrated with books, movies, and even a statue in New York’s Central Park. When a deadly infection called diphtheria swept through the isolated town of Nome, Alaska in 1925, Balto and a relay team of sled dogs traveled for six days across hundreds of miles in a raging blizzard to bring critical antitoxin to the town. 

[Related: Humans have partnered with sled dogs for 9,500 years.]

Balto is still helping people 90 years after his death, but this time, with his DNA. In a study published April 17 in the journal Science, scientists detail how they sequenced Balto’s genome to learn more about the genetics of the sled dogs of the 1920s and see how they compare to modern dogs.  

Balto was raised in a kennel by breeder Leonhard Seppala and belonged to a population of small, fast sled dogs that had been imported from Siberia in northern Russia. These dogs became known as Siberian huskies, but the modern versions of the breed, as well as modern sled dogs are quite different from Balto. Other living dog lineages that share this common ancestry with Balto include Greenland sled dogs, Vietnamese village dogs, and Tibetan mastiffs.

“It’s really interesting to see the evolution of dogs like Balto, even in just the past 100 years,” study co-author and postdoctoral researcher at the University of California, Santa Cruz Katherine Moon said in a statement. “Balto’s population was different from modern Siberian huskies, which have since been bred for a physical standard, but also from modern working Alaskan sled dogs.”

The team extracted DNA from  tissue samples of Balto’s taxidermied remains from the Cleveland Museum of Natural History  to investigate his genetic traits and ancestry. They found that Balto shared only part of his ancestry with Siberian huskies, and that he actually belonged to a population of working sled dogs that were more genetically diverse than modern breeds. 

The researchers also found evidence that his population was genetically healthier than modern breeds. “Balto came from a population of working dogs that were different from modern breeds and were adapted to harsh conditions,” said coauthor Beth Shapiro, an evolutionary biologist from UC Santa Cruz, in a statement.

To analyze Balto’s genome, the team needed to compare it to a dataset of 682 genomes from modern wolves and dogs, as well as an alignment of 240 mammalian genomes developed by the Zoonomia Consortium, an an international collaboration effort to find the genomic basis of shared and specialized traits in mammals.

[Related: Humans probably have big brains because we got lucky.]

According to Shaprio, a key innovation behind this study is the ability to align the genomes of hundreds of species so that corresponding positions in different genomes can be compared. Comparing these genomes can then reveal DNA sequences that are the same across species and haven’t been changed during millions of years of evolution. This stability is an indication that these parts of the genome are important, and these crucial bits are where mutations could be especially harmful. 

“A gene that’s on one chromosome in us is on a completely different chromosome in another species,” Shapiro said. “You need a tool that can line them up so you can see which parts of these genomes are the same and which are different. Without that it’s just a bunch of genomes of species that are very divergent.”

The study on Balto’s DNA used this approach to characterize genetic variation seen in Balto compared to modern dogs. Populations of working sled dogs like Balto were more “genetically healthy” than breed dogs due to lower burdens of rare and potentially damaging variations in their genes. The team also identified protein-altering, evolutionarily constrained variants in Balto’s genes related to tissue development, which could represent beneficial genetic adaptations. 

Variations in genes related to skin thickness, joint formation, coordination, and weight were also found, and Balto had a better ability to digest starch compared to Greenland sled dogs and wolves. However, Balto’s ability to digest starchy foods is still not as strong as modern dogs. 

The team was also able to use this genetic treasure trove from Balto’s genome to reconstruct his physical appearance, including his coat color, in more detail than even historic photos could reveal. “This project gives everyone an idea of what’s starting to be possible as more high-quality genomes become available to compare,” Moon said. “It’s an exciting moment because these are things we haven’t done before. I feel like an explorer, and once again Balto is leading the way.”

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Humans and chimpanzees share a common ancestor, but 4 to 6 million years ago they split off on different evolutionary paths. Chimps continued to walk on all fours and live in trees, while we lost our fur and grew past the need for a tail. But it was our large brains that set us the most apart from our closest relatives. The human brain (about the size of 10 tennis balls) is three times bigger than a chimp’s.

There are multiple theories for why we evolved large and complex brains. Some evolutionary biologists think humans developed bigger bodies as a response to environmental pressures such as living in open, unforested habitats that required more cooperation and thinking to catch prey. Others speculate our brains needed to grow to handle the information needed to manage social relationships. And in a new study published in Science today, geneticists offer a third explanation: We just got lucky.

Lead author Katie Pollard, the director of the Gladstone Institute of Data Science and Biotechnology in California, likes to think of it as rolling dice. Every time another member of a species is born, there’s a chance that mutations will spring up in their genome. Each new generation gets more opportunities to score big with tweaks in the gene pool that increase the odds of survival. These beneficial mutations are more likely to stick around as organisms thrive and pass them on to offspring. In the case of humans and brain size, eventually, the buildup of mutations would be reflected in changes in the overall genome, Pollard says.

These random mutations could have contributed to the 49 short DNA sequences in our genome called human accelerated regions (HARs). Pollard and her team were the first to find these segments back in 2006 when comparing the genomes of humans to chimpanzees. HARs work as gene enhancers, controlling which genes are turned up or down during embryonic development, especially for brain formation. 

[Related: Eating meat may not have been as crucial to human evolution as we thought]

HARs in humans are very similar in each individual but vary when compared to accelerated regions in other vertebrates like chimps, frogs, and chickens. Since the initial discovery, research has found a connection between HARs and multiple traits that make our species distinct. And while Pollard has spent a lot of time understanding how HARs helped humans evolve, the current study focuses on why HARs emerged in the first place. 

The team collected data from 241 mammalian genomes (in concert with the larger Zoonomia project) and identified 312 accelerated regions across all of them. Most of the accelerated regions identified acted as neurodevelopmental enhancers, indicating a connection to brain development. But when comparing human and chimp DNA sequences, 30 percent of HARs were in areas of the genome where the DNA was folded differently. This suggests the structural variations in the human genome likely came from a random mutation during reproduction. “Mutations happen all the time and everytime sperm and eggs get made, there are some mistakes that cause cuts, deletions, and other edits to the DNA,” explains Pollard. “Many of the mutations don’t make any difference, but now and then some have a positive effect and that’s actually very rare.” 

In this case, scrunching and folding up DNA in different ways seemed to help with fitting a copy of the genome in every cell of the body. “It’s a big surprise that genome folding is involved since it hadn’t been on anyone’s radar when studying human accelerated regions,” says Pollard. “We had been thinking of DNA as a text file in a big folder full of A, C, T, and G’s, and looking for patterns as you move linearly through the sequence.”

The folding change would have affected how enhancers regulated gene activity in early humans. Depending on how the DNA was folded, enhancers could have been situated near new sequences, giving them different genes to target and boost. In humans, it just so happened that most of the adjacent genes were involved in brain development. In other words, we won the mutation lottery.

“The main achievement of this study is the discovery that the evolutionary history of HARs is connected in some way with the complex dynamics of structural configurations of the human genome,” says Anastasia Levchenko, a genetic researcher for the Institute of Translational Biomedicine at Saint Petersburg State University in Russia who has previously studied HARs’s role in brain development. However, she would like to see more research on the sequence of events in the evolution of the human genome. For example, it’s possible that HARs appeared way earlier than the changes in our DNA folds, or that DNA folding is only one factor contributing to the creation of HARs.

[Related: This is the most complete map we have of the human genome]

What’s more, humans might have used other genetic pathways to develop different features from other animals. Pollard’s study is one of 11 papers published in Science today as part of the Zoonomia Project, an international collaboration that aims to understand the codes behind shared and specialized traits across hundreds of mammalian species. For example, Zoonomia researchers identified the distinct parts of Balto’s genome that helped the sled dog deliver a serum to a remote Alaskan village, as well as genetic variants in early humans that could play a role in modern-day diseases. Another paper focuses on using information from DNA to predict which species are more likely to face extinction. All together, identifying the different genomes will open the door to understanding mammalian evolution and what exactly makes us uniquely human. 

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Looking at poop can tell us a lot. Poop offers a window into all sorts of hidden worlds: bird microbiomes, clam habitats, recovering coral forests, and more. 

Excrement can also tell us about how and when animals went extinct thousands of years ago. A study published April 26 in the journal Quaternary Research looked at the fungal spores in the dung of the large animals, such as 20-foot-tall ground sloths and 1,000 pound armadillo-looking animals called armored glyptodonts, that roamed the Colombian Andes in South America during the Pleistocene. 

[Related: Ancient poop proves that humans have always loved beer and cheese.]

They found that the animals became extinct in not one, but two waves. The megafauna in this study first became locally extinct at Pantano de Monquentiva, a valley in Colombia surrounded by hills and near a bog, about 23,000 years ago and then again in the same area about 11,000 years ago. 

Spores of coprophilous fungi pass through the guts of these megafauna during their life cycle. The presence of these spores in sediment samples provides evidence that these long-extinct animals lived in a certain place and time. 

The team used samples found in a peat bog in Pantano de Monquentiva, about 37 miles from Bogota, Colombia. The findings offer a window back in time to better understand how the disappearance of large animals could transform ecosystems like they did all those millennia ago. 

“We know that large animals such as elephants play a vital role in regulating ecosystems, for example by eating and trampling vegetation,” Dunia H. Urrego, co-author and University of Exeter biologist and geographer, said in a statement. “By analyzing samples of fungal spores, as well as pollen and charcoal, we were able to track the extinction of large animals, and the consequences of this extinction for plant abundance and fire activity.

The team found that the Monquentiva ecosystem changed dramatically when the megafauna disappeared, with different plant species thriving and increased wildfires. The analysis of the fungal spores didn’t tell exactly which large animals were present, but it’s possible that the animals were either the giant sloth and armadillo, or even macrauchenids and toxodonts, two peculiar extinct animals reminiscent of today’s camels and rhinoceroses.

[Related: Our bravest ancestors may have hunted giant sloths.]

The study also found that when all of this plentiful megafauna disappeared, it had major effects on the ecosystem. Roughly 5,000 years after their disappearance, the megafauna began to live again. This reprieve was short lived, and they all went extinct in a second wave of extinction 11,000 years ago. While the team does not know the direct causes of this, a number of factors like plant extinctions, climate changes, increased hunting by humans, and even a meteorite spike are potential causes.

“After the megafauna vanished, plant species at Monquentiva transitioned, with more woody and palatable plants (those favored by grazing animals), and the loss of plants that depend on seed dispersal by animals,” co-author and geographer also at the University of Exeter Felix Pym said in a statement.  “Wildfires became more common after the megafauna extinctions – presumably because flammable plants were no longer being eaten or trampled upon. 

With the planet’s current biodiversity crisis in mind, the study points to the importance of conserving local plants and watching fire activity before the value humans gain from nature completely disappears. 

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The unusual looking mudskipper has a startling face, and a fascinating backstory. The fish is actually amphibious and has evolved traits that ensure its survival in both water and on land. They have eyes on the top of their heads for better aerial vision and also use oxygen from their water stored in their gill chambers to breathe on land. However, the mudflat-dwelling fish’s ability to blink its eyes is shedding light on how our own ancestors evolved from living in the water to walking on land.

A study published April 24 in the Proceedings of the National Academy of Sciences (PNAS) found that the blinking behavior serves many of the same functions of our blinking, and it may be part of that suite of traits that allowed tetrapods to evolve on land. Tetrapods are the group of animals, including today’s amphibians, birds, reptiles and mammals, that evolved to exist on land in a rapid turn of events roughly 375 million years ago.

[Related: Our four-legged ancestors evolved from sea to land astonishingly quickly.]

Animals blink to keep the eyes wet and clean and protect them from injury. Sometimes, blinking can even be a form of communication. Humans and other tetrapods blink constantly through the day and despite it being a subtle action, it is quite complex. Strangely enough, mudskipper’s blink lasts roughly the same length of time as a human’s. 

“Studying how this behavior first evolved has been challenging because the anatomical changes that allow blinking are mostly in soft tissues, which don’t preserve well in the fossil record,” co-autor and Penn State University biologist Thomas Stewart said in a statement. “The mudskipper, which evolved its blinking behavior independently, gives us the opportunity to test how and why blinking might have evolved in a living fish that regularly leaves the water to spend time on land.”

To better understand how mudskippers evolved the ability to blink, the team analyzed blinking using high-speed videos. They compared the mudskippers’ anatomy with a closely related water-bound fish that doesn’t blink. Mudskippers blink with eyes that bulge out of the top of their heads, similar to a frog’s eyes. They momentarily retract their eyes down into the sockets, when they are covered by a sketchy membrane called a dermal cup. 

“Blinking in mudskippers appears to have evolved through a rearrangement of existing muscles that changed their line of action and also by the evolution of a novel tissue, the dermal cup,” co-author and Seton Hall University biologist Brett Aiello said in a statement. “This is a very interesting result because it shows that a very rudimentary, or basic, system can be used to conduct a complex behavior. You don’t need to evolve a lot of new stuff to evolve this new behavior — mudskippers just started using what they already had in a different way.”

To understand why the mudskippers blink on land, the team looked to the roles that blinking plays in other tetrapods. Tears in humans are critical to keeping the eye’s cells oxygenated and healthy, so the team looked to see if mudskippers blink to keep their eyes wet when exposed to the air.  

[Related: Tiktaalik’s ancient cousin decided life was better in the water.]

“We found that, just like humans, mudskippers blink more frequently when confronted with dry eyes,” said Aiello. “What’s incredible is that they can use their blinks to wet the eyes, even though these fish haven’t evolved any tear glands or ducts. Whereas our tears are made by glands around our eyes and on our eyelids, mudskippers seem to be mixing mucus from the skin with water from their environment to produce a tear film.”

They also found that blinking in mudskippers is triggered to protect the eye from injury as well as  clearing their eyes from possible debris. The finding suggests that mudskipper blinking appears to fulfill blinking’s three major functions—protecting, cleaning, and maintaining moisture.

“Based on the fact that mudskipper blinking, which evolved completely independently from our own fishy ancestors, serves many of the same functions as blinking in our own lineage, said Stewart. “We think that it was likely part of the suite of traits that evolved when tetrapods were adapting to live on land.”

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Is the phase “nice guys finish last” actually true? Unfortunately for all the soft-hearted among us, brutish behavior can be an effective path to power and dominance in both humans and chimpanzees. A study published April 24 in the journal PeerJ Life and Environment found that the male chimpanzees who exhibited greedy, irritable, and bullying personalities reached a higher social status. These rascals were also more successful at producing offspring. 

[Related: Adolescent chimpanzees might be less impulsive than human teens.]

However, the team is still plagued by a puzzling question from these findings: if being mean is the key to success, why isn’t every chimp a bully? 

For the study, the team followed 28 male chimpanzees living in Tanzania’s Gombe National Park. A previous study had found that  these particular chimpanzees had a few members that  are more sociable whereas others are loners. Some of the chimps had overbearing personalities, and some were more easy-going. And, of course, there are a handful that are more quick to pick fights with others. 

Tanzanian field researchers performed personality assessments on the chimpanzees based on years of near-daily observations of how each animal interacted with others and behaved among the group. They found that a personality combination of high dominance and low conscientiousness helped the male chimpanzees fare better in life than the others, but it still doesn’t answer the evolutionary puzzle of why personality differences exist at all. 

A long held theory is that different personality traits matter at different points in an animal’s life or that certain traits that are a liability when an animal is young may pay off in old age. 

“Think of the personality traits that lead some people to peak in high school versus later in life,” Alexander Weiss, co-author and comparative psychologist at the University of Edinburgh, said in a statement. “It’s a trade-off.” 

The team tested the theory using almost 40 years of data that goes back to famed primatologist Jane Goodall’s early research at Gombe. Across the lifespan, the same personality traits were linked to both high reproductive success and high social rank. 

[Related: Popular chimpanzees set hand-holding trends for the whole group.]

Something else must be behind the diversity of chimpanzee personality. The “best” personality to have could depend on social or environmental conditions. Gender could matter too—a trait that is beneficial to males could cost a female. If this is true, then “genes associated with those traits would be kept in the population,” Weiss said. Further study is needed to confirm this idea. 

The suggestion that animals have distinct personalities was considered taboo not too long ago, with Goodall herself accused of anthropomorphism with her descriptions. Scientists have studied animals ranging from squid to birds, finding evidence of distinct personalities. These quirks, idiosyncrasies, and ways of relating to the world around them remain reasonably stable over time and across situations.

Like with measures of human personality, personality ratings for animals have also been proven to be as consistent from one observer to the next. “The data just doesn’t support the skepticism,” Weiss said.

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Carnivorous plants come in a variety of shapes and colors—and it’s often their looks that help them attract their prey. However, these floral tricksters may use a different scene to attract their dinner: smell. A small study published this month in the journal PLOS One found evidence that different species of Sarracenia, a genus of North American pitcher plant, produces scents that are directed at certain groups of prey.

[Related: Two newly discovered Andes Mountain plant species have an appetite for insects.]

Sarracenia pitcher plants typically make their home in bogs and in poor soil throughout North America. Their signature purple or reddish flowers are actually leaves which form a cup called the “pitcher”  filled with digestive enzymes.  If an insect gets too close to the plant, the pitcher traps it and digests the insect to help supplement their diet in a nutrient-poor home. 

The odor of carnivorous plants hasn’t been well-studied by humans, but has been suspected for over a century. Charles Darwin wrote about the unique plants about 150 years ago, but it’s been more difficult to find concrete evidence of its olfactory mechanisms. 

“Of the signals involved in communication, odor is probably the most cryptic to humans,’ co-author and carnivorous plant expert French National Centre for Scientific Research Laurence Gaume said in a statement. “In plants, it is often correlated with other plant characteristics such as nectar, shape and visual signals, which make it difficult to disentangle its effect from others.”

In this new study, a team identified the odor molecules emanating from four types of pitcher plants. The scents appear to correlate with the types of incense that wound up inside of the pitchers. The chemicals that make up some of the scents are similar to ones known to act as signals to certain insects, which may mean the pitcher plants have evolved to take advantage of their prey’s senses.

“It offers potentially interesting avenues in the field of biological control, and one can imagine drawing inspiration from the olfactory cues of these pitcher plants to control plant pests, for example,” said Gaume.

The team grew Sarracenia purpurea and three of its hybrids with other pitcher plants in a lab.  

They found that all of the pitchers produced a scent that was similar to more generalist plants that are pollinated by many different species. This can allow them to cast a wide net for prey, but they noted that there were subtle differences in the volatile organic compounds that they produced. 

[Related: Dying plants are ‘screaming’ at you.]

The pitchers attracting butterflies and bees were rich in compounds like limonene, a chemical that gives citrus fruits their unique smell. The aroma comes from a class of chemicals found in the scents of around two thirds of flowering plants which attract these pollinators.

Meanwhile, S. purpurea also had an odor that was high in fatty acid chemicals known to attract parasitoid wasps and possibly other insect predators. Wasps and insects made up a large part of the plant’s diet, which suggests that the scent could be targeting them directly. 

The team found that both the odor of a pitcher and its dimensions could help predict the prey caught by a plant about 98 percent of the time. This is not definitive proof, but it suggests a possible link between a pitcher plant’s scent and its prey. 

Since carnivorous plants cannot move to hunt for their prey like a lion or a shark, smells can help them not only find food, but communicate with other plants. Plants being eaten can release scents that tell other plants nearby to get their defenses ready or produce a smell that attracts predators. 

Plants that are pollinated by animals often rely on scents to attract pollinators, like bees. Anything that hides their scent–like air pollution–can cause a drop in the number of pollinators that can find them. 

Further studies could help explain how carnivorous plants that are pollinated by insects can attract some for pollination and other for food. For example, the most important pollinators of Venus fly traps are never found inside its traps, and scent could play a role in this. 

 “However, we remain cautious because our results are currently based on correlations. Even with strong correlations, further tests are necessary to investigate whether the different insect types are indeed attracted to particular scents,” said Gaume.

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When entering into disaster scenarios, robots still have a major downside—their inability to recover when they inevitably crash into things. Scientists, however, have taken a page out of biology’s playbook, as they often do, to create a drone that can bounce back when met with various obstacles. 

Think of a bird landing on a tree branch—in order to do so, they likely have to collide with a few smaller branches or leaves in the process of touching down. But, their joints and soft tissues cushion these bumps along the way, and their feet are built precisely to lock themselves in place without straining a muscle. When a drone opts for a similar route, taking on a bunch of collisions on the way to their destination, it’s a little bit more dramatic. “They don’t recover; they crash,” Wenlong Zhang, an associate professor and robotics expert at Arizona State University said in a release. 

“We see drones used to assess damage from high in the sky, but they can’t really navigate through collapsed buildings,” Zhang added. “Their rigid frames compromise resilience to collision, so bumping into posts, beams, pipes or cables in a wrecked structure is often catastrophic.” 

Zhang is an author of a recent paper published in Soft Robotics wherein a team of scientists designed and tested a quadrotor drone with an inflatable frame, apparently the first of its kind. The inflatable frame acts almost like a blow-up suit, protecting the drone from any harsh consequences of banging into a wall or another obstacle. It also provides the kind of soft tissue absorption necessary for perching—the team’s next task.

[Related: Watch this bird-like robot make a graceful landing on its perch.]

After studying how birds land and grip onto branches with their taloned feet, the team developed a fabric-based bistable grasper for the inflatable drone. The grasper had two unpowered “resting states,” meaning it can remain open or closed without using energy, and reacts to impact of landing by closing its little feet and gripping hard onto a nearby object.

“It can perch on pretty much anything. Also, the bistable material means it doesn’t need an actuator to provide power to hold its perch. It just closes and stays like that without consuming any energy,” Zhang said in the release. “Then when needed, the gripper can be pneumatically retracted and the drone can just take off.”

A more resilient type of drone is crucial for search and rescue scenarios when the path forward may be filled with debris, but the authors could also see this kind of creation being useful in monitoring forest fires or even exploration on other planets.

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A herd of African elephants stands above a cliff nearly 600 feet tall in the first episode of the new documentary series Secrets of the Elephants. After a brutal dry season in Zimbabwe, an elephant matriarch must guide her herd down the cliff in search of water. Their enormous three-to-four-ton bodies are not built for this kind of expedition—they use their trunks to test the ground. To complicate the descent, they must be mindful of the younger elephants, and reassure and soothe the babies with their tails along the way. Everyone is tense as they navigate the steep path of the gorge, including  the wildlife experts and filmmakers watching from the sidelines. 

“It was amazing, even for me, to see that,” veteran conservationist and elephant advocate Paula Kahumbu tells PopSci during a recent interview. In the 30-something years she’s studied African elephants, Kahumbu had never seen them inching down a cliff this way. In the documentary, she described how just watching the process made her legs feel weak and her body unsteady, and couldn’t imagine what it must be like for these giants of the savanna.

Broken into four episodes—Savanna, Desert, Rainforest, and Asia—Secrets of the Elephants presents the lives and issues that elephants face as incredibly nuanced and interconnected. Human-caused climate change and decades of ivory poaching have taken its toll, but beneath that lies the more complex and interwoven problems of disappearing elephant range, fences that impede their movements, and culling individuals who encroach on farmland. When people are killed or injured by the powerful mammals, Kahumbu says governments are then forced to take actions due to the loss of property or life. 

“Retaliation and intolerance towards elephants is now by far, the number one threat to elephants across east Africa” says Kahumbu. Most of Africa’s elephants live in the eastern and southern part of the continent in various habitats. Both species of African elephants are listed as critically endangered by the International Union for Conservation of Nature; their latest assessment found that the number of African forest elephants fell by more than 86 percent over the last 31 years, and the population of African savanna elephants decreased by at least 60 percent over the last 50 years. Their Asian relatives are listed as endangered, with an estimated 48,000 to 50,000 left in the wild.

The series explores this tension between two incredibly smart terrestrial mammals, elephants and humans—but more importantly, the striking similarities between them. Their parallel existence goes back millennia, as both humans and elephants evolved out of Africa at the same time. Elephants are incredible problem solvers and mirror human adaptability so well that they can typically figure out any deterrent or barrier that communities devise to keep them out. The elephants then pass the knowledge down generations. 

Their innate intelligence and ability to pass down survival skills can also benefit conservation efforts. As an example, Kahumbu cites successful elephant underpasses that help link one group of elephants found near Mount Kenya with their relatives in the forests, plains, and the Aberdares Mountains, while keeping them away from the area’s enormous wheat farms. “Once the elephants figured out that that’s the safe way to get from this mountain to the other mountain, they started not only using it, but teaching each other to use it. There are very few animals which will teach each other and elephants are one of them,” she explains.

[Related: Ivory poaching has triggered a surge in elephants born without tusks.]

Despite being one of the most studied animals on the planet, elephants keep surprising experts with their unique features and complex behaviors. They rarely get sick, with less than five percent getting cancer compared to about 25 percent of humans, and are even known to self medicate with the plants around them. Female elephants also do not fade into obscurity or die once they are unable to reproduce. In both African and Asian species, they likely play an integral grandmother role similar to that of humans and possibly orca whales. Kahumbu describes elephant matriarchs as the knowledge keepers: They know where to eat and find water, where to rest, and even keep internal maps of the vast landscapes they traverse.

The series depicts the female elephants’ ability to take generational insights and adapt it to the constant challenges and changes, sometimes with bizarre results. In one rare case, an elephant in Zimbabwe named Nzou who lost her entire family to poachers when she was two years old now finds herself the matriarch to a herd of buffalo at age 50. “It’s very hard to say much because it’s just such a one-off strange thing that happened,” Kahumbu explains. “We’re increasingly seeing unusual wild animal behaviors. Adopting buffaloes is kind of funny, and it’s also quite sad.”

She didn’t fit in with other groups of elephants when rescuers tried to rehome her, but she found her place among a more unique family. Now, she has to figure out how to manage an unusual herd without the benefit of the years of living among older female elephants—but her instinct to lead is still strong.  

“In a way, it teaches us that just like humans, there are certain needs we all have, and we’re going to have to get them somehow,” says Kahumbu.

[Related: Elephants and monkeys are fighting climate change in ways humans can’t.]

Another central theme of the four-part series is the value that local people’s wisdom holds for both conservation and science communication. Experts from Namibia in southern Africa and Borneo in southeast Asia made the documentary possible through their historic observations of elephants and guidance. “A lot of things which we filmed have never been filmed or seen on camera before, but actually, a lot of it has been known by local people on the ground for a very long time,” says Kahumbu. “We are asking people for local knowledge, but we’re involving them in the series and getting them on camera as well.”

Engaging communities on the ground and connecting the rest of the world with their stories through film could be a big step in further protecting elephants. Reaching younger and wider audiences, particularly in Africa, is part of why Kahumbu has seamlessly moved from the research space into more policy, advising, and education in an effort to save elephant lives.

“What’s shifted for me dramatically is this realization that we’re running out of time,” says Kahumbu. “I think that unleashing young people with their own creativity to identify how they can help is what I’d love to see happen as a result of this TV series. That connection is very powerful and very important.”

Secrets of the Elephants premieres on Friday, April 21 on National Geographic. All four episodes will stream on Earth Day (April 22) on Disney+ and Hulu. 

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Aging has been said to be a “privilege denied to many”—and gray hair typically accompanies that privilege. Gray hair can also be caused by stress, but scientists might be closer to figuring out exactly why even the most colorful hair turns gray with age. A study published April 19 in the journal Nature found that certain stem cells have a unique ability to move between the growth compartments in hair follicles, but they get stuck and lose their ability to mature and maintain hair color as people age. 

[Related: We finally know why stress turns your hair white.]

The melanocyte stem cells (McSCs) in hair follicles are responsible for producing and maintaining the pigment in our hair. Every hair follicle stores immature melanocyte stem cells, and when they’re needed, the cells travel from one part of the follicle to another. When they reach other parts of the follicle, proteins turn them into more mature pigment-producing cells, and give hair its hue. Inside these follicle’s compartments, McSCs are exposed to different levels of maturity-influencing protein signals as a person ages. 

According to the study, which McSC cells from mice, as hair ages, sheds, and then repeatedly grows back, more McSCs get stuck in a stem cell compartment called the hair follicle bulge. While there, they stay put, unable to mature or be able to move between follicle compartments. They also do not travel back to their original location where WNT proteins would have prodded them to regenerate into pigment cells.

“Our study adds to our basic understanding of how melanocyte stem cells work to color hair,” study co-author and New York University computer engineer Qi Sun said in a statement. “The newfound mechanisms raise the possibility that the same fixed-positioning of melanocyte stem cells may exist in humans. If so, it presents a potential pathway for reversing or preventing the graying of human hair by helping jammed cells to move again between developing hair follicle compartments.”

To learn more about how stem cells behave during different phases of hair growth, the team tracked and took images of the individual cells in mouse fur. The stem cells actually traveled back and forth within the hair follicle and even transitioned into their mature, pigment-producing state and then out of it again as they moved.

As time continued, the McSCs couldn’t keep up this process, and a hair falling out and growing back takes its toll on the follicle. Eventually, the stem cells stopped making this journey through the follicle and stopped getting protein signals to make pigment. From then on, any new hair growth does not get the melanin needed to produce hair color. 

[Related: Alopecia patients finally have an FDA-approved hair-loss treatment.]

To explore this effect more, the ream plucked hair from mice to stimulate a faster growth cycle. The experiment led to a build up of McSCs stuck in storage that no longer produced melanin, and the fur turned from dark brown to a distinguished salt-and-pepper. 

“It is the loss of chameleon-like function in melanocyte stem cells that may be responsible for graying and loss of hair color,” co-author and NYU pharmacologist and cell biologist Mayumi Ito, said in a statement.  “These findings suggest that melanocyte stem cell motility and reversible differentiation are key to keeping hair healthy and colored.
Some next steps for the team include investigating how to restore motility in these stem cells so that they can move back to the compartments that produce pigment. Until then, consider joining the “gray hair revolution” of people embracing those beautiful gray strands.

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For at least 22,000 years, the African penguin has been struggling to survive because of habitat loss.  Scientists are now peering into the past to learn more about why to better help the lovable feathered creatures  today and in the future. A study published April 20 in the African Journal of Marine Science paints a paleo-historical picture of where these climate change survivors lived and moved to as the last Ice Age came to a close—and how that changed over time. 

According to the study, the African penguin,also called the black-footed penguin, the Cape penguin, or the Jackass penguin, lived on 15 large islands off the coast of southern Africa more than 20,000 years ago. During this period called the Last Glacial Maximum, massive ice sheets dominated a huge portion of the Earth, and it ended about 15 to 20,000 years ago. Upon this climate shift sea levels began to rise as ice melted, effectively sinking the islands. The rising water reduced the suitable nesting habitat for the penguin colonies by tenfold over the next 22,000 years. 

[Related: The march of the penguins has a new star: an autonomous robot.]

To help them paint this picture, the team used topographical maps of the ocean floor to find potential former islands that lay 32 to 426 feet below today’s sea levels. Penguins use islands as breeding spots to escape predators on the mainland and also need suitable foraging grounds for sardines and anchovies within about a 12 mile radius. 

With the assumption that sea levels were lower during the last Ice Age, the team identified 15 large islands that possibly stood off the southwest coast of Africa, with the largest being about 115 miles long and laying 426 feet below the surface of the sea. When taking the rate of sea level rise over the past 15,000 to 7,000 years into account, they found 220 islands that would have been suitable nesting spots for penguins. 

By comparison, some of the largest modern-day islands with penguins off the southwest coast of Africa are Robben Island less than two miles long, Dassen Island less than one mile, and Possession Island also less than a mile long, which all clock in at less than two miles long.

The study estimates that between 6.4 million and 18.8 million individual penguins could have lived among these islands during the Last Glacial Maximum, before the numbers began to plummet. 

These changes in habitat availability over the past 22,000 years “could have had a massive effect on penguin populations,” co-author and Stellenbosch University ecologist Heath Beckett said in a statement. “These populations are now experiencing additional human pressures on top of this in the form of climate change, habitat destruction, and competition for food.” 

According to Beckett, this new paleo-historical image of penguins all over the islands of southern Africa stands in contrast to the current reality of a post-1900 collapse of the African penguin population. Dassen Island was once teeming with about 1.45 million penguins, but South Africa’s entire African penguin population collapsed to 21,000 breeding pairs by 2011. As of 2019, they dropped even further to 13,600, and roughly 97 percent of the current population in South Africa is supported by seven breeding colonies.

[Related: Ceramic ‘igloos’ could keep African penguins cool and cozy.]

“Changing sea levels would have necessitated the need for multiple relocations of breeding colonies of African penguins on time-scales of centuries, if not even shorter time-scales, and intense competition for breeding space as island habitat became greatly reduced in size,” said Beckett. “This historical flexibility of response provides some leeway for conservation managers to make available suitable breeding space, even in mainland sites, as long as appropriate nesting sites are made available.”

Some further questions brought on by this research surround relocation for the penguins, and analyzing just how much more the species can handle as human pressures continue to rise and food competition heats up. 

However, despite the alarming drops in population and their continued struggle, the team points out that these findings highlight the African penguin’s resilience as a species and that this could be leveraged for its conservation and management in an uncertain climate.

“It’s a total survivor and given half a chance, they will hang on,” co-author and Stellenbosch University biologist Guy Midgley concluded in a statement.  “Island hopping saved it in the past, they know how to do this.” 

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Today is a very special holiday where a skunky smell permeates the air. If you’re celebrating 4/20, Popular Science has the perfect lineup of dope science stories to make you everyone’s favorite bud. Don’t puff puff pass on this one!

Essential cannabis accessories

First things first, everyone needs some cannabis supplies before lighting up. But with so many twists on glassware and other options, how do you decide? From vaporizers to grinders to pen batteries, PopSci’s roundup of essential cannabis accessories will walk you through the choices.

A step-by-step guide to rolling a joint

Rolling a joint can’t be that hard, right? Wrong. Thankfully, in honor of 4/20, our DIY step-by-step guide will explain both the art and the science of rolling a joint, with advice straight from some of New York City’s expert budtenders. It’s the perfect refresher for veterans and crash course for newbies, complete with photos, detailed instructions, and material recommendations.

Can CBD help you chill? Here’s what we know so far.

CBD, THC’s sister molecule, has been working its way into various products as part of a budding industry. CBD is legal in more US states than cannabis, and can be added to almost any product as long as it has less than 0.3 percent THC. It’s a great alternative for those looking for stress relief, or don’t want the psychoactive effects of cannabis itself. Still have some questions about CBD? It’s not a panacea, but it may be worth trying out.

Is growing weed sustainable? The answer is complicated.

Using cannabis products to ease climate anxiety might be a Catch-22. Researchers say it’s hard to measure the environmental impact of today’s celebrated plant: Grow operations across the US take up a lot of water, land, and energy. Here’s what we know about the sustainability of cannabis.

Can you overdose on weed?

All substances have their risks, what about weed? Well, thankfully its not possible to overdose in the traditional sense, but overdoing it does pose some safety threats. Before you celebrate 4/20, listen to this Ask Us Anything podcast on the side effects of weed to gain some insights on responsible consumption.

The tasty chemicals flavoring the edible cannabis boom

Cannabis may have a distinctive smell, but a little-known aspect to users and non-users alike is that each strain has a special chemical composition. Like wine with its various aromas (such as floral, fruity, or earthy) different strains of cannabis possess a signature scent and taste. What makes them unique? Terpenes, or “terps,” are aromatic compounds found in many herbs and flowers. There are hundreds of known kinds that yield diverse flavors and effects. PopSci reported a comprehensive overview on the science of terpenes, ending with a list of the most buyable varieties.

Is marijuana a performance-enhancing drug? The best evidence says no.

Unfortunately for many athletes, cannabis use still falls on the list of prohibited substances. These regulations are in place to prevent the use of performance-enhancing drugs and ensure fair competition, but does cannabis really belong on the same list as steroids? Learn why the scientific reasoning behind cannabis regulations in sports might be lacking.

Cannabis gets its high-inducing power from ancient viruses

The next time a friend thanks a higher power for cannabis, remind them to appreciate viruses for their genetic contributions. (At the very least, it was a joint effort.) The psychoactive and medicinal effects of cannabis probably evolved from ancient viruses Mapping the genome of the plant posed a challenge to researchers as an illicit substance, but as it slowly became legal in different states over the past two decades, they dove deep into its background. What better time than 4/20 to learn the evolutionary history of cannabis.

Why German scientists got cows stoned

Nobody wants animals to get high on our supply, but these German scientists did it on purpose with cows. Not to laugh at the animals’ “pronounced tongue play,” as researchers described: They wanted to test if leftover organic matter from the hemp industry could be fed to livestock, reducing waste and curbing methane emissions from regular hay and soy. The German study led to some especially silly bovine behavior and THC-spiked milk.

Does CBD show up on a drug test?

Using cannabis products might lead to a positive drug test that could cost you a job or other opportunities. For those that want the stress-reducing effects of cannabis, but have to keep off the grass, consider quality products with this CBD drug test and product guide.

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Snails are notoriously slow, excellent ecosystem engineers, and invasive and destructive pests in many gardens and on farms. Their eating methods are also pretty gnarly if you can get up close and personal. A German photographer named Jens Braun from YouTube channel Another Perspective released a video of a snail munching on a strawberry, with close-up details offering a fresh perspective on an unusual mollusk.

Brown garden snails are about one inch in diameter at maturity and have a brown and gray color pattern. They are most active when the air and ground are damp, mostly sliding around during the nighttime and early morning hours. They are native to Great Britain, Western Europe, and along the borders of the Black and Mediterranean seas, but can now be found across most of the southeastern US and both coasts. 

[Related from PopSci: Sea snail venom could lead to better insulin for diabetics]

Snails typically are omnivores, but the main staples of their diet are ornamental plants, flowers, weeds, veggies, and of course fruits.  Snails and their close relatives, the slugs, eat with their jaw and a flexible band of microscopic teeth called a radula. During a process called rasping, thousands of radula scrape up food particles, then they use their jaw to cut off larger pieces of food like leaves to be rasped.

Part of why snails are considered such a pest is that they can severely damage orchards by feeding on ripening and ripe fruit, as well as the leaves and bark growing on young trees. The telltale signs of fruit damage are circular chewed areas of the fruit’s rind, and leaves typically appear chewed along their margins. 

Citrus orchards are particularly vulnerable to becoming snail buffets since their watering methods and weed control creates a moist environment where snails can thrive. Last summer was a particularly rough snail year in South Florida, after snails that can be the size of a fist bounced back after a decade-long battle to eradicate them.  

[Related: It’s still a mystery how snails ended up scattered around the globe.]

Snails are also hermaphroditic—meaning all snails that reach reproductive age can lay eggs. This happens up to six times during a mating season, typically in the late spring and early summer. They lay up to 80 eggs per month in shallow depressions in the topsoil after mating. The eggs hatch after being in the soil for 14 to 40 days, and they will eat their eggs and even the eggs of their siblings to get enough calcium to harden their shells. 

While many snails are harmless to humans aside from being a garden pest, cone snails contain a paralyzing venom that can even be fatal in humans. When injected, the venom puts the victim into excitotoxic shock, which makes them unable to move within only a few seconds. Then, the snail opens its mouth wide to engulf all of the prey in a slow and painful death. Understanding how this venom works could help scientists produce better pain medication.

If you are keen to keep snails from eating your produce, raking over soil, using study plants in pots instead of seedlings, and searching for the pests during damp and mild evenings and transporting them to a compost heap can help.

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For animals spread all across the realms–air, land, and water–traveling speed is affected by how well they can cool off. The findings of a study published on April 18 in the open access journal PLOS Biology found that an animal’s traveling speed is limited by how effectively they can shed the excess heat generated by its muscles, particularly for animals that weigh over one ton. 

Travel is crucial to the survival of many animals, and certain physical features can dictate how far animals can migrate and where they find food. This is becoming even more challenging in a human-dominated world with more fragmented habitats and climate changing limiting food and water resources. 

[Related: We are eating large animals into extinction.]

In this study, the team used data on 532 species to develop a computerized model to look at the relationship between an animal’s size and traveling speed. The data only included freely moving animals in the wild based on radar tracking devices or video recordings, excluding studies on animals in captivity. 

As animals became larger, the traveling speeds increased, until they reached one ton, or about 2,000 pounds. At that point, the traveling speeds leveled off and began to decrease. When looking for possible reasons why the animals were slowing down, they concluded that the larger animals needed to slow down to avoid overheating changed the shape of the curve in the results. 

The results were the same for aquatic animals even though they live in water, which can cool the body down. Medium-sized animals, such as wolves, typically showed the fastest sustained speeds. 

“The new study provides a way to understand animal movement capacities across species and can be used to estimate any animal’s traveling speed based on its size,” co-author and biologist Alexander Dyer from the German Centre for Integrative Biodiversity Research said in a statement. “For example, this approach can be applied to predict whether an animal might be able to move between habitats fragmented by human development, even when the details of its biology are unknown.”

[Related: Ceramic ‘igloos’ could keep African penguins cool and cozy.]

In theory, increased temperatures due to climate change will affect all animals and not just the larger ones. Some animals are already evolving smaller bodies in response to the heat. According to the World Meteorological Organization, an eight year period from 2014 to 2022 were the eight warmest years on Earth’s record. 

“We anticipate that large animals are potentially more susceptible to the effects of habitat fragmentation in a warming climate than previously thought and therefore more prone to extinction. But this needs further investigation,” co-author and biologist also at the German Centre for Integrative Biodiversity Research Myriam Hirt said in a statement.

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For spiders, spinning their silky webs is a matter of survival. Those that don’t weave good enough silk to spin an insect-trapping web will have a much tougher, or even impossible, time getting enough food to eat. Since spiders are found throughout world, the more fine-tuned their webs are to their environment, the better they will work. 

In a study published April 18 in the journal Frontiers in Ecology and Evolution, biologists found that the glue that makes orb weaver spiders’ webs so sticky actually evolves faster than the spiders’ genes. 

[Related: Black widows battle their even deadlier cousins in a brutal spider war.]

“Discovering the sticky protein components of biological glues opens the doors to determining how material properties evolve,” study co-author and Washington and Lee University biologist Nadia Ayoub said in a statement. “Spider silk fibers and glues represent a fantastic model for answering such questions since they are primarily made of proteins and proteins are encoded by genes.”

Like the individual threads of a tapestry, each strand in an orb weaver spider’s web works to capture food. The web’s stiff frame absorbs the impact of the prey before it is trapped by the sticky lines so that the spider can tackle its food. A special glue that is synthesized in the spider’s aggregate glands makes the lines of the web sticky by absorbing water from the atmosphere. The glue should be altered to achieve the best stickiness for the amount of humidity in the air in the region where the spider lives. Since there are numerous species of orb weaver spiders living in many environments, the team on this study believed their glue must adapt to humidity levels. 

To investigate this glue adaptation strategy, the team focused on two species– Argiope argentata (A. argentata) and Argiope trifasciata (A. trifasciata). A. argentata lives in dry environments and is native to Southern California. The team had them build webs in a lab, but were fed a diet comparable to their prey and compared the glue droplet volume found in nature to make sure they were equivalent to what they weave in nature. A. trifasciata lives in humid environments all over the world and the team collected webs from them in the wild. 

They analyzed the proteins in the glue and the droplets’ material properties and found that the droplets from the dry-living A. argentata spiders are smaller than those from the more humidity prone A. trifasciata, and also absorb less water as local humidity increases. A. argentata’s glue also had smaller protein cores that occupied a smaller proportion of the droplet’s volume and absorbed less water from the atmosphere. 

[Related: How researchers leveled up worm silk to be tougher than a spider’s.]

The stiffness of these protein cores in the droplets affected the toughness of the glue droplets and the toughness of A. argentata’s protein core decreased as the humidity went up. A. argentata thread glue droplets were generally sticker and  more closely spaced.

When the team analyzed the proteins in the glue to understand how these differences in their material properties arise from these proteins, they found that the proteins appeared in different proportions, even though they were similar. A. argentata glue had the protein products of four genes which didn’t appear in A. trifasciata glue. The extra proteins and a more balanced ratio of the glue’s key AgSp1 and AgSp2 proteins may explain the greater toughness of this glue and its lower capacity for water absorption.

“Despite the dramatic differences in material properties, the two species share most of their protein components,” co-author and Virginia Tech biologist Brent Opell of Virginia Tech said in a statement. “The sequences of these proteins are also similar between species, but the relative abundance of individual proteins differs. Modifying the ratios of proteins is likely a rapid mechanism to adjust material properties of biological glues.”

According to the team, one of the limitations to this study includes that it only looked at two species, and the relationship between proteins and web material properties are not quite to scale yet. To address this, the team is documenting protein components and the material properties of a diverse set of species.

More study on spider silk and their properties could also have some wider scientific and technological applications. “Spider silks and glues have huge biomimetic potential. Spiders make glues with impressive properties that would have applications in industry, medicine, and beyond,” said Opell.

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Scientists have found dozens of species of coastal invertebrates organisms thriving Oscar the Grouch style in the Great Pacific Garbage Patch. Roughly 620,000 square miles long, or twice the size of Texas, the floating garbage heap is located between Hawaii and California. Five large spinning circular currents constantly pull trash towards the center of the patch, and it is considered the largest accumulation of ocean plastic on Earth.

These creatures found thriving in trash like crabs and anemones are normally found along the coasts, but the study published April 17 in the journal Nature Ecology & Evolution says that dozens of species have been able to survive and reproduce on the plastic garbage.  

[Related: A close look at the Great Pacific Garbage Patch reveals a common culprit.]

“This discovery suggests that past biogeographical boundaries among marine ecosystems—established for millions of years—are rapidly changing due to floating plastic pollution  accumulating in the subtropical gyres,” co-author and marine ecologist Linsey Haram said in a statement. Haram conducted this research while working at the Smithsonian Environmental Research Center.

The team only recently discovered these “neopelagic communities,” or floating communities of organisms living in deep ocean waters. Organic matter in the ocean decomposes within a few years at most. But plastic debris lasts significantly longer, thus giving the animals a place to live and procreate.  

The team analyzed 105 plastic samples that were collected by The Ocean Cleanup, a non-profit organization that is working on scalable solutions to get rid of ocean plastic, during their 2018 and 2019 expeditions. The samples were found in the North Pacific Subtropical Gyre, a large zone that makes up most of that northern Pacific Ocean and is the largest ecosystem on Earth. Incredibly, 80 percent of the plastic trash that the team looked at showed signs of being colonized by coastal species. Some of the coastal species were even reproducing in their plastic homes, such as the Japanese anemone.

“We were extremely surprised to find 37 different invertebrate species that normally live in coastal waters, over triple the number of species we found that live in open waters, not only surviving on the plastic but also reproducing,” said Haram. “We were also impressed by how easily coastal species colonized new floating items, including our own instruments—an observation we’re looking into further.”

[Related: Ocean plastic ‘vacuums’ are sucking up marine life along with trash.]

While biologists already knew that coastal species can travel towards the open ocean on floating debris or on ships, it was long believed that these species couldn’t thrive or establish new communities at sea. Differences in temperature, water salinity, and the available nutrients between these two environments seemed too vast, but human-caused changes to the ocean ecosystems have forced marine biologists to rethink these ideas. 

“Debris that breaks off from this [garbage] patch constitutes the majority of debris arriving on Hawaiian beaches and reefs. In the past, the fragile marine ecosystems of the islands were protected by the very long distances from coastal communities of Asia and North America,” co-author and UH Mānoa oceanographer Nikolai Maximenko said in a statement. “The presence of coastal species persisting in the North Pacific Subtropical Gyre near Hawai‘i is a game changer that indicates that the islands are at an increased risk of colonization by invasive species.”

According to data from the United Nations Environment Programme (UNEP), the world produces roughly 460 million tons of plastic annually and this figure could triple by 2060 if government action is not taken soon. Some individual actions to reduce plastic use is shopping more sustainably, limiting use of single-use plastic like water bottles and plastic utensils, and participating in beach and river clean-ups.

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PLANTS ARE CRUCIAL to human survival, even when there’s no sunlight. But dealing with darkness is second nature for someone with a green thumb like Howard Levine, chief scientist for NASA’s International Space Station (ISS) Research Office. Nurturing leaves outside Earth’s atmosphere is not only important for cycling nutrients and water during future space voyages, but also helps alleviate the cooped-up feeling astronauts experience. “On the ISS, you’re up there for six months at a time. People often say it’s like being in the bathroom with six of your best friends,” says Levine, who has been growing plants in orbit for decades.  

Space might be an extreme example, but cramped, dark dwellings exist on the ground too. Keeping your houseplants alive in windowless rooms, in shadowy corners, or during short winter days can be a challenge. Luckily, there are strategies to help your flora stay lush and verdant, even when their sunny source of energy is limited. 

Mini indoor greenhouses

Darkness usually means a dip in natural heat. Colder temperatures slow our bodies down, and that’s true for plants too. The chemical reactions that control their growth decelerate and sometimes stop.  

In Iceland, horticulturist James McDaniel uses geothermal heat in his greenhouses to protect his plants from the wintry cold. Each of the structures has holes beneath that stretch deep to a pocket of steaming-hot water, he explains. “You can funnel that [steam] into the pipes through the greenhouse and use natural ventilation to keep the temperature a set range.” 

But you don’t need volcanic energy to run a mini indoor greenhouse, which can be as simple as a repurposed IKEA cabinet. A heater can add warmth, although you might want to pair it with a humidifier to keep from drying your houseplants out. For individual plants, glass dome cloches can trap heat from limited sunlight and also enclose water vapors, which protect plants from the crisp air conditioner in the summer and the prickly heater in the winter. 

Grow lights

Plant grow lights provide an easy and accessible energy boost in dim or pitch-black spaces. These specialized beams sport different features, colors, and prices. LEDs, for instance, are the cheapest and most energy-efficient option, using about a third of the electricity of old sodium lightbulbs.

While most devices stick to a warm white spectrum, plants respond differently to various illuminating hues. In Levine’s experiments on Earth, red light worked well for the slender flowering plants Arabidopsis. But in the ISS’s weightless environment, they stretched into funny shapes until he started adding blue lights. He eventually found a middle ground and doused the plants in green light at the request of astronauts who missed the familiar color.  

Bright surfaces

If electricity is a limiting factor, you can try to reflect light with mirrors or aluminum foil. Even brightening up your space with white decor, like a light-colored tablecloth, will cast a little glow onto your plants. While it’s not comparable to using a grow lamp or the sun (reflections don’t deliver as much energy), it could offer plants an extra boost. 

The makeup of your indoor garden will dictate how much brightness you need to add, Levine explains. Some flora, including lettuce and tomatoes, need more light than those like Arabidopsis; new seedlings need less light than fully grown plants. As you choose your seeds and seedlings, research their native ranges to learn how much sunshine they’d naturally get.

Plants are ultimately adaptable. They can stretch their stems toward available light sources or produce extra chlorophyll, the pigment that absorbs whatever luminescence is available. “Even though they may not be getting all the light that they would like for optimum growth, they’ll still grow,” says Levine. With only a little extra help, you and your plants can conquer the darkness. 

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Since its discovery nearly 70 years ago, paleontologists have debated the lineage of the mysterious “Tully monster.” The six-inch-long, stalk-eyed creature lived over 300 million years ago in the seas of modern-day Illinois. Its unique anatomy has long challenged researchers, making it difficult to identify as either a vertebrate or invertebrate–one of the first steps of classification. 

Vertebrates are animals with spines, including mammals, birds, reptiles, amphibians, and fish. Invertebrates are animals without spines, including insects, arachnids, crustaceans, mollusks, annelids, and more. The Tully monster, or Tullimonstrum gregarium, was a soft-bodied marine animal, so its fossilized remains do not show clear evidence of a backbone. In 2016, researchers claimed to have identified a pale gut-like structure as a notochord, a primitive spine, signaling a vertebrate affinity. 

Now, researchers at the University of Tokyo believe they have solved the mystery of Tullimonstrum gregarium’s lineage, finding characteristics that point to an invertebrate identity. Their findings were published in the journal Palaeontology on April 17, 2023.

Amateur collector Francis Tully found the first fossils in Illinois’ Mazon Creek formation in 1955, a fossil bed known for its treasure trove from the Carboniferous period. He then took his unidentified ‘monster’ to the Field Museum of Natural History, where it confounded paleontologists and opened up a debate that would last decades. It was first described in a paper in 1966 and became the Illinois state fossil in 1989.

[Related: A gator-faced fish shaped like a torpedo stalked rivers 360 million years ago]

So far, researchers have been unable to determine whether the fossil was a vertebrate or invertebrate, one of the first bases of taxonomic identification. Invertebrates emerged first in the form of soft-bodied organisms, such as sponges, jellyfish, and worms over 600 million years ago. Vertebrates evolved after, during the Cambrian explosion about 540 million years ago. Both sides of the debate have evidence to support them, and it is still an open discussion. If found to be a vertebrate, the Tully monster would fill a gap in evolutionary history, connecting jawless fish (such as lampreys and hagfish) to jawed fish. 

Recent findings suggest the opposite. Researchers at the University of Tokyo analyzed 3D imaging of 153 Tully monster fossils from Mazon Creek. They found structures that point to it being an invertebrate chordate, like a lancelet, a small eel-like marine invertebrate which evolved 500 million years ago. The Tully monster could also potentially be a radically modified protostome, a clade of animals encompassing insects and crustaceans, which first evolved around 540 million years ago along with vertebrates during the Cambrian explosion. 

“The most important point is that the Tully monster had segmentation in its head region that extended from its body. This characteristic is not known in any vertebrate lineage, suggesting a nonvertebrate affinity,” Tomoyuki Mikami, a doctoral student in the Graduate School of Science at the University of Tokyo at the time of the study and currently a researcher at the National Museum of Nature and Science, said in a press release. 

The researchers found structures consistent with those of invertebrates, such as body segmentation, vertical tail fins and head shape. They also analyzed body parts thought to prove similar to those of vertebrates, such as a tri-lobed brain, tectal cartilage (supporting the eyes and optic nerves) and fin rays. They found that these structures, though similar, are not comparable to those of vertebrates.

[Related: One wormy Triassic fossil could fill a hole in the evolutionary story of amphibians]

Using three-dimensional imaging techniques, the authors described the morphology of the Tully monster’s proboscis and its stylets—thin, needle-like structures with a similar function as teeth, in depth. According to the research, these structures are inconsistent with the keratinous teeth found in lampreys and hagfish, two vertebrates thought to be distant relatives.

In one of the earliest studies on the unique animal published in 1969, researchers stated that “our conception of the diversity of the organic world is based upon a small sample consisting almost entirely of animals with preservable hard parts.” The Tully monster, however, has few of such parts—not unlike jellyfish and worms, which lack hard skeletal structures and leave only impressions in sediment as they are fossilized. Studying what little evidence we have of ancient soft creatures is crucial for reconstructing the history of life, as a significant number of Earth’s creatures became extinct without leaving any fossils behind.

“More and more research is needed to extract important clues from Mazon Creek fossils to understand the evolutionary history of life,” Mikami said.

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Following an usually wet winter in the West, California is beginning to emerge from a serious drought. The state, however, is now beautifully awash in wildflowers. The state is seeing a “super bloom,” similar to the Instagram famous super bloom of 2019. 

A unique combination of sun, rain, temperature, and wind set the stage for the arrival of desert wildflowers in the late winter and early spring, according to the California Department of Parks and Recreation. 

[Related: Powerful atmospheric river pummels California with even more rain and flooding.]

“California’s desert state parks are cautiously optimistic in expecting a ‘good’ to ‘better than average’ wildflower bloom this late winter and spring seasons depending on the continued weather conditions,” the department said on their website. 

This super bloom only happens after particularly wet seasons, which typically follow years of drought. Many parts of California saw more rain in the first few months of this year than in all of 2022, according to local CBS affiliate KFMB.

During the dry years, many annual wildflower seeds lay dormant in fragile layers of soil. If enough rain arrives, they germinate and the flowers can burst through. The areas with blooms typically see large and dense qualities of wildfires covering the landscape and some of the most beautiful blooms are in desert landscapes. Depending on the region, California poppies, sand verbena, desert sunflowers, evening primrose, popcorn flowers or desert lilies could be growing. 

In the Antelope Valley north of Los Angeles, California poppies gleam bright orange. During the 2019 super bloom, thousands of tourists and influencers came out to view the poppies, which led to the unfortunate trampling of some of the flowers. New rules for both safety and conservation have been put in place in Lake Elsinore to protect the poppy bloom in nearby Walker Canyon. In an advisory on how to see the flowers safely and responsibly, California State Parks Director Armando Quintero asked visitors not to “doom the bloom.” Visitors are urged to stay on trails and not pick any of the flowers. 

The poppies aren’t the only stars of the season. In California’s Central Valley, Purple phacelia and yellow goldfields abound at Carrizo Plain National Monument, a grassland roughly 70 miles west of Bakersfield. 

[Related: Don’t go to Death Valley looking for a ‘Super Bloom.’]

This year’s bloom is an opportunity for scientists who study rare plants to study ecosystems that have been lost to development or agriculture over the years. Heather Schneider, a rare plant biologist with the Santa Barbara Botanic Garden told The New York Times that the sustained colder temperatures and precipitation would likely give researchers more time to study wildflowers than in past wet years.  “This is how we feed our souls,” said Schineder.

Since different flower species thrive in subtly different conditions and times of year, botanists have predicted that this year’s wildflower season may extend through the spring and into the summer, especially in higher elevations. 

To safely and respectfully view the superbloom, visitors can consult the state’s safety tips and consult the bloom calendar for updates on what is blooming where. 

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You may or may not have heard of xenobots, a kind of Frankenfrog creation that involves researchers turning frog embryo cells into tiny bio-machines that can move around, push or carry objects, and work together. These ephemeral beings were first made by a team of scientists from Tufts University and the University of Vermont in 2020. 

The goal behind building these “bots” was to understand how cells communicate with one another. Here’s a breakdown of the hard facts behind how xenobots actually work, and what they are currently used for. 

But why would someone want to build robots out of living components instead of traditional materials, like metal and plastic? One advantage is that having a bio-robot of sorts means that it is biodegradable. In environmental applications, that means if the robot breaks, it won’t contaminate the environment with garbage like metal, batteries, or plastic. Researchers can also program xenobots to fall apart naturally at the end of their lives. 

How do you make a xenobot?

The building blocks for xenobots come from the eggs laid by the female African clawed frog, which goes by the scientific name Xenopus laevis. 

Just like with a traditional robot, they need other essential components: a power source, a motor or actuator for movement, and sensors. But with xenobots, all of these components are biological.

A xenobot’s energy comes from the yolk that’s a part of all amphibian eggs, which can power these machines for about two weeks with no added food. To get them to move, scientists can add biological “motors” like muscle or cardiac tissue. They can arrange the motors in different configurations to get the xenobots to move in certain directions or with a certain speed.  

“We use cardiac tissue because cardiac cells pulse at a regular rate, and that gives you sort of an inchworm type of movement if you build with it,” says Blackiston. “The other types of movement we get are from cilia. These are small hair-like structures that beat on the outside of different types of tissues. And this is a type of movement that dominates the microscopic world. If you take some pond water and look, most of what you see will move around with cilia.” 

Scientists can also add components like optogenetic muscle tissues or chemical receptors to allow these biobots to respond to light or other stimuli in their environment. Depending on how the xenobots are programmed, they can autonomously navigate through their surroundings or researchers can add stimulus to “drive” them around. 

“There’s also a number of photosynthetic algae that have light sensors that directly hook onto the motors, and that allows them to swim towards sunlight,” says Blackiston. “There’s been a lot of work on the genetic level to modify these to respond to different types of chemicals or different types of light sources and then to tie them to specific motors.”

[Related: Inside the lab that’s growing mushroom computers]

Even in their primitive form, xenobots can still convey some type of memory, or relay information back to the researchers about where they went and what they did. “You can pretty easily hook activation of these different sensors into fluorescent molecules that either turn on or change color when they’re activated,” Blackiston explains. For example, when the bots swim through a blue light, they might change color from green to red permanently. As they move through mazes with blue lights in certain parts of it, they will glow different colors depending on the choices they’ve made in the maze. The researcher can walk away while the maze-solving is in progress, and still be in the know about how the xenobot navigated through it.  

They can also, for example, release a compound that changes the color of the water if they sense something.  

These sensors make the xenobot easy to manage. In theory, scientists can make a system in which the xenobots are drawn to a certain wavelength of light. They could then shine this at an area in the water to collect all of the bots. And the ones that slip through can still harmlessly break down at the end of their life. 

A xenobot simulator

Blackiston, along with collaborators at Northwestern and University of Vermont, are using an AI simulator they built to design different types of xenobots. “It looks sort of like Minecraft, and you can simulate cells in a physics environment and they will behave like cells in the real world,” he says. “The red ones are muscle cells, blue ones are skin cells, and green ones are other cells. You can give the computer a goal, like: ‘use 5,000 cells and build me a xenobot that will walk in a straight line or pick something up,’ and it will try hundreds of millions of combinations on a supercomputer and return to you blueprints that it thinks will be extremely performant.”

Most of the xenobots he’s created have come from blueprints that have been produced by this AI. He says this speeds up a process that would have taken him thousands of years otherwise. And it’s fairly accurate as well, although there is a bit of back and forth between playing with the simulator and modeling the real-world biology. 

The xenobots that Blackiston and his colleagues use are not genetically modified. “When we see the xenobots doing kinematic self-replication and making copies of themselves, we didn’t program that in. We didn’t have to design a circuit that tells the cells how to do kinematic self replication,” says Michael Levin, a professor of biology at Tufts. “We triggered something where they learned to do this, and we’re taking advantage of the native problem-solving capacity of cells by giving it the right stimuli.” 

What can xenobots help us do?

Xenobots are not just a blob of cells congealing together—they work like an ecosystem and can be used as tools to explore new spaces, in some cases literally, like searching for cadmium contamination in water. 

“We’re jamming together cells in configurations that aren’t natural. Sometimes it works, sometimes the cells don’t cooperate,” says Blackiston. “We’ve learned about a lot of interesting disease models.”

For example, with one model of xenobot, they’ve been able to examine how cilia in lung cells may work to push particles out of the airway or spread mucus correctly, and see that if the cilia don’t work as intended, defects can arise in the system.

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This article is republished from The Conversation.

Trees can die suddenly or quite slowly.

Fire, flood or wind can cause a quick death by severely damaging a tree’s ability to transport water and nutrients up and down its trunk.

Sometimes a serious insect attack or disease can kill a tree. This kind of death usually takes from a few months to a couple of years. Again, a tree loses its ability to move water and nutrients, but does so in stages, more slowly.

A tree can also die of what you might call old age.

I am a scientist who studies trees and the web of living things that surround them. The death of a tree is not exactly what it seems, because it directly leads to new life.

Different trees, different life spans

Trees can live an incredibly long time, depending on what kind they are. Some bristlecone pines, for instance, are among the oldest known trees and are more than 4,000 years old. Others, like lodgepoles or poplars, will have much shorter life spans, from 20 to 200 years. The biggest trees in your neighborhood or town are probably somewhere in that range.

You’ve probably noticed that different living things have different life spans – a hamster is generally not going to live as long as a cat, which isn’t going to live as long as a person. Trees are no different. Their life spans are determined by their DNA, which you can think of as the operating system embedded in their genes. Trees that are programmed to grow very quickly will be less strong – and shorter lived – than ones that grow very slowly.

But even a tough old tree will eventually die. The years and years of damage done by insects and microscopic critters, combined with abuse from the weather, will slowly end its life. The death process may start with a single branch but will eventually spread to the entire tree. It may take a while for an observer to realize a tree has finally died.

You might think of death as a passive process. But, in the case of trees, it’s surprisingly active.

The underground network

Roots do more than anchor a tree to the ground. They are the place where microscopic fungi attach and act like a second root system for a tree.

Fungi form long, superfine threads called hyphae. Fungal hyphae can reach much farther than a tree’s roots can. They gather nutrients from the soil that a tree needs. In exchange, the tree repays fungi with sugars it makes out of sunlight in a process known as photosynthesis.

You might have heard that fungi can also pass nutrients from one tree to another. This is a topic that scientists are still working out. Some trees are likely connected to other trees by a complex underground network of fungi, sometimes called the “wood wide web.”

How the wood wide web functions in a forest is still not well understood, but scientists do know that the fungi forming these networks are important for keeping trees healthy.

Afterlife of a tree

Before it topples over, a dead tree can stand for many years, providing a safe home for bees, squirrels, owls and many more animals. Once it falls and becomes a log, it can host other living things, like badgers, moles and reptiles.

Logs also host a different kind of fungi and bacteria, called decomposers. These tiny organisms help break down big dead trees to the point where you would never know they had existed. Depending on the conditions, this process can take from a few years to a century or more. As wood breaks down, its nutrients return to the soil and become available for other living things, including nearby trees and fungal networks.

A tree leaves a legacy. While alive, it provides shade, home for many animals and a lifeline to fungi and other trees. When it dies, it continues to play an important role. It gives a boost to new trees ready to take its place, shelter to a different set of animals and, eventually, nourishment for the next generation of living things.

It’s almost as if a tree never truly dies but just passes its life on to others.

Editor’s note: This story has been updated to emphasize that much remains unknown about the relationship between trees and fungi.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Two new studies are shedding light on not only early hominid evolution, but are turning back the evolutionary clock on how early grassy woodlands appeared on the African continent.

The first new study, published April 13 in the journal Science, suggests that life in the open woodlands of Africa and a leafy diet may have influenced the upright stature of humans’ ape ancestors. 

[Related: Ancient DNA confirms Swahilis’ blended African and Asian ancestry.]

Anthropologists had long believed that our ancestors evolved an upright torso to pick fruit in forests, since some of our favorite produce grows on the spindly peripheries of trees. Large apes would have needed to distribute their weight on the branches stemming up from the trunk and then reach up with their hands to grab the fruit. Performing this task is easier if an ape is upright, since it can grab the branches better with their hands and feet. If an ape’s back is horizontal, the hands and feet are typically underneath the body, which makes it harder to move outward to the smaller branches of the tree. 

However, new research using a 21-million-year-old fossilized ape called Morotopithecus suggests that early apes actually ate the leaves in a seasonal woodland with a broken tree canopy and open grassy areas. The team believes that this landscape, and not fruit in closed canopy forests, possibly drove the ape’s upright structure.   

“The expectation was: We have this ape with an upright back. It must be living in forests and it must be eating fruit. But as more and more bits of information became available, the first surprising thing we found was that the ape was eating leaves. The second surprise was that it was living in woodlands,” co-author and University of Michigan paleoanthropologist Laura MacLatchy said in a statement.

Both papers grew out of a collaboration of international paleontologists called the Research on Eastern African Catarrhine and Hominoid Evolution project (REACHE). MacLatchy’s study focused on the a 21-million-year-old site in eastern Uganda called the Moroto site. Here, the team found fossils in a single rock layer. Fossils of other mammals and evidence of plant life were found in this layer and these lines were used to recreate Morotopithecus’ environment.

In a companion paper, also published April 13 in Science, another team used environmental proxies to reconstruct nine fossil ape sites across Africa, including the Moroto site during the early Miocene. The proxies revealed that grasses were actually all over the area 21 million years ago, instead of the previously determined 7 to 10 million. 

The team then found that the plants in this landscape were “water stressed,” which means that they lived in seasonal periods of rain and of aridity. These shifts mean that apes would have had to rely on something other than fruit to survive. These findings indicate that Morotopithecus likely lived in an open woodland that was punctuated by broken canopy forests made up of shrubs and trees. 

[Related: The ‘granddaddy’ of all early hominins walked on Earth a lot longer than we thought.]

“For the first time, we’re showing that these grasses are widespread, and it’s this general context of open seasonal woodland ecosystems that were integral in shaping the evolution of different mammalian lineages, including and especially in our case, how different ape lineages evolved,” study co-author and University of Michigan biological anthropologist John Kingston said in a statement.

The nine sites in both studies are scattered across eastern equatorial Africa, which is an area large enough for the team to develop a better regional picture of what these landscapes looked like 23 million to 16 million years ago during the early Miocene. At this time, the East African Rift forming the region saw huge change in topography. This upheaval as the Earth was pulling apart resulted in regional climate and its vegetation.  

“These open environments have been invoked to explain human origins, and it was thought that you started to get these more open, seasonal environments between 10 and 7 million years ago,” MacLatchy said. “Such an environmental shift is thought to have been selected for terrestrial bipedalism—our ancestors started striding around on the ground because the trees were further apart. Now that we’ve shown that such environments were present at least 10 million years before bipedalism evolved, we need to really rethink human origins, too.” 

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It’s hard to identify individual members of another species, unless they have sufficient visual distinctions. Every squirrel looks more or less the same, herd animals seem like a hoard of clones, and you may have once mistaken a lookalike stray for your pet. But when you look closely, small details characterize an individual from the rest of their species. Researchers at the University of California Berkeley proved the same applies for a rare species of octopus. 

The team discovered that the Pygmy zebra octopus has stripe patterns as unique as human fingerprints, allowing even humans to tell them apart. They also found that after about two weeks of age, their stripe patterns become permanent and distinctive. They published their recent findings in PLOS One.

[Related: What human and octopus brains have in common]

Octopuses’ intelligence, complex behavior, and color-changing abilities have led the animal into the limelight, both inside academia and out. There are over 300 species that live off the coasts of every continent. One is the Pygmy zebra octopus (Octopus chierchiae), also known as the lesser pacific striped octopus, coming in at about the size of a grape when fully grown. It has brown and tan stripes, fitting its name, and is native to the Pacific coast of Central America. 

Researchers confirmed that each individual has a stripe pattern unique to them by photographing 25 Pygmy zebra octopuses in a lab for nearly two years. They took photos of the specimens every week, from hatching to adulthood. Then, they gathered 38 untrained volunteers to participate in a survey to see whether or not they could identify individual octopuses based on their stripes. The survey consisted of 20 photo comparisons, each taken no more than 25 weeks apart.

The volunteers’ average accuracy was 84.2 percent, and about half of all participants scored at least 90 percent. Additionally, no individual question was answered incorrectly by a majority of participants. By analyzing stripe patterns, the volunteers’ accuracy shows that a majority of people can discern one individual from another. Given the time difference between photos, the results also indicate that people can identify an individual after several months have passed, even between juvenile to adult life cycle stages. 

[Related: Female octopuses will chuck seashells at males who irk them]

Tracking wild animals is a challenge for many researchers, but octopuses are especially challenging to monitor. Their reclusive and mysterious behavior make them hard specimens to track. And without some sort of tag or marker, researchers struggle to identify individuals if seen again. Cephalopod researchers employ various, sometimes invasive identification techniques, including tagging, tattooing, and branding. All these practices at the very least risk harming octopuses’ soft, delicate tissues and causing unnecessary pain. Tagging, one of the least harmful options, is also imperfect. Octopuses can easily slip out of tags without bones, and if it’s attached to their flesh, they can even rip them off.

If researchers could track octopuses by photography alone, it could be a game changer for the field. In the study, the researchers highlight photography as a “a largely inexpensive, non-invasive, non-extractive, and widely accessible technique to produce high-quality data” and recommend it as an identification and tracking method for future research. 

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A team of scientists from the United States and the Netherlands have discovered a new species of bat based on the oldest bat skeletons ever discovered. The findings are described in a study published April 12 in the journal PLOS One. 

The new species is named Icaronycteris gunnelli (I. gunnelli) in honor of the late Gregg Gunnell, a Duke University paleontologist who died in 2017 and is remembered for his contributions to understanding fossil bats and evolution. 

[Related: How killing vampire bats to slow rabies can go wrong.]

The now extinct I. gunnelli lived in Wyoming roughly 52 million years ago and the current scientific consensus is that bats rapidly diversified on multiple continents during this time in history. There are currently over 1,460 living bat species  found almost all over the world, except for the Earth’s polar regions and a few remote islands. 

The bat skeletons are about 1.5 inches long and were found near Kemmerer, Wyoming in the Green River Formation. The formation spans parts of Wyoming, Colorado, and Utah and is home to an extensive fossil deposit from the early Eocene—about 56 million to 47.8 million years ago.  Scientists have found more than 30 bat fossils in the last 60 years within the formation. Until finding this new species, however, they believed all of them were from the same two extinct species, Icaronycteris index and Onychonycteris finneyi.

“Eocene bats have been known from the Green River Formation since the 1960s. But interestingly, most specimens that have come out of that formation were identified as representing a single species, Icaronycteris index, up until about 20 years ago, when a second bat species belonging to another genus was discovered,” study co-author Nancy Simmons, curator-in-charge of the American Museum of Natural History’s (AMNH) Department of Mammalogy said in statement. Simmons helped describe the second species named Onychonycteris finneyi in 2008, but always thought that there might be even more Eocene bats out there. 

Recently, scientists from the Naturalis Biodiversity Center in the Netherlands began to look closely at Icaronycteris index by collecting measurements and other data from museum specimens to put together a dataset.

“Paleontologists have collected so many bats that have been identified as Icaronycteris index, and we wondered if there were actually multiple species among these specimens,”  co-author and evolutionary biologist Tim Rietbergen said in a statement. “Then we learned about a new skeleton that diverted our attention.”

[Related: Both bats and humans test out talking as infants.]

The well-preserved I. gunnelli skeleton in this study was purchased by a private collector in 2017 and was subsequently purchased by AMNH. The team compared the skeleton with Rietbergen’s extensive bat dataset and saw that it clearly stood out as a new species.

A second fossilized Icaronycteris gunnelli skeleton that was discovered at this same quarry in 1994. It eventually made its way to the Royal Ontario Museum in Toronto and was also identified as this new species. 

While there are fossilized bat teeth from Asia that are slightly older than these skeletons, the two I. gunnelli fossils represent the oldest bat skeletons ever found, according to the team. The I. gunnelli skeletons are also the oldest bat fossils that have been recovered from the Green River Formation, but they are not the most primitive, meaning not the earliest on the bat evolutionary tree. According to the team, this supports the idea that the bats in the region evolved separately from other Eocene era bats.

“This is a step forward in understanding what happened in terms of evolution and diversity back in the early days of bats,” said Simmons.

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Plenty of species have traits evolved for more than one purpose. Deer antlers are built-in weapons as well as seductive doe-magnets. Octopus suckers can trap prey in their suction but also taste and smell. Bright colors in frogs signal danger to predators while flaunting reproductive viability to potential mates. The Luna moth has uniquely shaped wings that thwart predation from bats, but what else might they be good for? How does one determine the evolutionary role of a trait? 

In two recent complementary studies published in Behavioral Ecology and Biology Letters earlier this year, researchers expanded our understanding of the adaptation by testing the role of wing tails against sexual selection and bird predation.

Luna moths are native to the Eastern half of North America. Like all silk moths, they have distinctive long, trailing tails on their hindwings, or “twisted, cupped paddles” as lead author of both studies and doctoral student at the Florida Museum of Natural history Juliette Rubin said in a statement. Bats use echolocation to detect the position of objects with reflected sound, but the moth’s wing shape reflects sound waves in a way that makes the flying mammals aim for the ends of their wings. In a flap of a wing, the moth just barely dodges their predators. 

[Related: What bats and metal vocalists have in common]

First, the researchers wanted to see if the wing tails also played a role in sexual selection. When female Luna moths are ready to mate, they perch in one spot and release pheromones. Males, with extremely sensitive antennae, can detect and follow a pheromone trail, according to the University of Florida’s entomology department. Then, the female has her pick of suitors. 

In the first experiment, researchers placed a female moth in a flight box with two males: one with intact wings and one with the wing tails removed. Initial data suggested that females preferred tails over no-tails, but further trials demonstrated otherwise. When researchers removed tails by clipping them, the resulting damage may have hindered these males’ performance in the first trial, allowing the intact males to mate successfully.

They recreated the tail/no-tail experiment by removing tails from both males, and re-gluing them to one male, while placing glue only on the hindwings of the other. Researchers found no significant difference in mating success between them. 

To ensure the glue did not confound the results, researchers conducted an additional experiment with two intact males, one with glue on the hindwings. Similarly, they had equal mating success.

Though their elegance is attractive to us humans, the experiment revealed that Luna moth wing tails aren’t the result of sexual selection. 

Then, researchers wanted to see if the moths’ tails had any obvious drawbacks. They help moths to survive bats, a species that relies on echolocation, but what about visually-oriented predators? 

Luna moths sit still during the day, since flying in broad daylight with their large bright green wings would make them easy targets. To test whether or not their tails would have any impact on daytime predation, researchers wrapped pastry dough around mealworms and molded them to the size and shape of real Luna moths. They attached full wings and wings without tails to each half. They placed the replicas around branches and leaves in an aviary, and introduced Carolina wrens. 

The wrens ate the fake moths at the same rate regardless of wing type, indicating that the tails had no effect on whether or not birds could locate them. Some research suggests that birds rely on search images, mental representations of objects, when they are searching for prey. They use visual cues, such as the shape of moth wings, to distinguish between the prey from patterns in the background. So, the wrens may ignore the hindwing tails, using the overall shape of Luna moths to identify food, according to the press release.

[Related: A new technique reveals how butterfly wings grow into shimmery wonders.]

These experiments show that despite being a noteworthy feature to humans, the Luna moths’ tails do not play a role in attracting a mate, nor do they affect predation by birds.

“When we see these really obvious physical features in animals, we’re often drawn into stories we’ve heard about them,” Rubin said in the statement. “A trait that’s obvious to us, as visual creatures, might not stand out to the predators that hunt them, and the traits that we think are dynamic and alluring might not seem that way to a potential mate.”

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If the black long sea cucumber  (Holothuria leucospilota) was a superhero, they might have quite a bit in common with a famous blue and red web slinger from Queens, New York. This sea cucumber has a comedic, but incredibly useful, way to ward off the hungry predators that stalk these strange creatures. When provoked, they will tear a hole in the wall of their butts and shoot out a tangle of sticky, noodle-like goo.  

The process is described in a study published April 10 in the journal Proceedings of the National Academy of Sciences (PNAS) and the unique defense mechanism can entangle and stop predators in their tracks. The expendable tangles are called the Cuvierian organ and look like a mass of white spaghetti that the cucumber has expelled from its butt. 

The organ is made of amino acids in repeating sequences. These proteins give the organ some strength and have unique arrangements of the proteins. Repeating amino acid sequences are also found in silkworm threats and spider webs. 

The Cuvierian organ is at the bottom of the sea cucumber’s respiratory tree, where the cucumbers breathe as well as poop. The organ contains hundreds of dangling tubes, and the sea cucumber can self-amputate it and fully regrow it in as quick as 15 days.

[Related: Sea cucumbers have a secret superpower.]

For the study, the team followed the molecular pathway that triggers the Cuvierian organ’s deployment, and found that piercing the area with a needle or grazing the skin activated the goopy sensation. However, applying direct pressure didn’t cause the reaction.  

These tubules can expand up to 20 times their original length with water pumping inside from the respiratory tree. The tubules become sticky upon contact with any surface and cling to the who or whatever is touching it. After being entangled in the butt goo, the aggressor sometimes even dies of starvation. 

Once a sea cucumber is safe from attack, it will likely crawl away from the deadly butt goo web. Scientists often find them partially hidden under clumps of seaweed, corals, or boulders. They then go back to their usual behaviors,  filtering organic matter from the sand and recycling nutrients like calcium back into the water by pooping them out. Corals and other animals can then eat up the nutrients. 

[Related: Watch these tiny bugs catapult urine with their butts.]

The team also found amyloid-like patterns in the proteins located within the Cuverian organ’s outer membrane. The brains of human patients with Alzheimer’s disease typically contain higher levels of amyloid plaques, but these proteins are used by marine organisms like barnacles as a strong adhesive. 

“This study provides the first genomic insights into defensive ensnarement in a representative species of [sea cucumber],” they write.

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Climate change has deteriorated the habitats of many migratory birds, permanently altering the timing of their expeditions. However, birds may be fighting back by changing their own plans. 

A study published April 11 in the journal Ecology finds that birds can partially compensate for these changes. They do so by delaying the start of spring migration and completing the journey faster, but this strategy does come with the cost of a decline in overall survival. 

“We found that our study species, the American redstart, can migrate up to 43 percent faster to reach its breeding grounds after delaying departure from wintering grounds in Jamaica by as much as 10 days,” co-author and Georgetown postdoctoral fellow Bryant Dossman said in a statement. “But increased migration speed also led to a drop of more than 6 percent in their overall survival rate.”

[Related: Migratory birds in the Eastern US are struggling to adapt to climate change.]

American redstarts breed in the trees and woodlands of southern Canada and the northeastern United States. They can lay two to five eggs at a time and both parents feed their young. According to the National Audubon Society, warblers like the redstart are often called ‘the butterflies of the bird world,’ for their ability to flit among treetops. The iconic redstart may live up to that nickname more than other warblers for its speed and colorful wings.

Some of the ways that birds like the redstarts can speed up the migration are by flying faster and making fewer or shorter stops to refuel. The speedier voyages  help compensate for the delayed departures, but can’t entirely make up for the lost time. According to the team on this study, individuals can recover about 60 percent of the lost time to a 10-day delay, but the birds will still be late to their breeding grounds. 

Jamaica, where some of the redstarts spend their non-breeding seasons, has become an increasingly dry climate in recent decades. The dryness means fewer insects, which are the mainstay of the redstart’s diet. It now takes the birds longer to get into the physical condition needed for the rigors of migration. Climate change is also causing the plants to bloom sooner and the insects to emerge sooner on the breeding grounds. 

“On average, migratory songbirds only live a year or two, so keeping to a tight schedule is vital. They’re only going to get one or two chances to breed,” said Dossman. “Longer lived birds are less likely to take the risk of speeding up migrations because they have more chances throughout their lives to breed and pass on their genes.”

The team from Cornell University, the University of Maryland, and Georgetown University used 33 years of American redstart migration departure data in tandem with automated radio tracking and light-level tags. They compared the birds’ expected departure date with their actual departure date to see how it has changed over time. 

[Related: Birds are so specialized to their homes, it shows in their bones.]

“Understanding how animals can compensate is an important part of understanding where the impacts of climate change will play out,” said co-author and Georgetown University biologist Peter Marra, in a statement.  “In this case, we may not lose a species entirely, but it is possible that populations of some species may go extinct locally due to climate change.” 

Activities at the redstart’s wintering grounds, such as not having enough food to eat, also carry over into the bird’s breeding season. While the redstart population is stable and increasing in much of its breeding range, eBird trend maps show that the species is declining in southern Quebec, Canada, and the northeastern US. 

“The good news is that birds are able to respond to changes in their environment,” Dossman said. “They have some flexibility and variation in their behaviors to begin with, but the question is, have they reached the limit of their ability to respond to climate change?”

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Unlike most primates, elephants will happily munch on a banana without removing its peel. However, one special female elephant at the Berlin Zoo named Pang Pha has taught herself how to peel a banana, according to a new study published April 10 in the journal Current Biology. Pang Pha reserves the task for bananas that are yellow-brown in color and first breaks the fruit before shaking it out and then collecting the pulp. The thick peel is left behind, possibly for for someone else to slip on.  

The authors of the study believe that she likely learned this peeling behavior by watching her caretakers feed bananas to her, and the findings show how elephants in general have some special manipulative and cognitive abilities.

[Related: Scientists may have figured out why elephants exhibit complex emotions.]

“We discovered a very unique behavior,” co-author and Humboldt University of Berlin neuroscientist Michael Brecht said in a statement. “What makes Pang Pha’s banana peeling so unique is a combination of factors—skillfulness, speed, individuality, and the putatively human origin—rather than a single behavioral element.”

Pha eats green or yellow bananas whole, completely rejects the brown ones and peels the brown spotted bananas that are typically perfect for baking banana bread before eating them. The team first noticed this after Pha’s caretakers mentioned this unusual banana peeling talent, but when they brought her nice green and yellow bananas, she didn’t peel them 

“It was only when we understood that she peels only yellow-brown bananas that our project took off,” said Brecht.

Additionally, Pha will change her behavior when yellow-brown bananas are offered to a group of elephants, and she will eat many whole bananas first and save the last one to peel later. Anecdotal reports and online videos have shown other elephants peeling bananas, but more studies and observations are needed to determine how common a phenomenon it really is. None of the other Berlin Zoo elephants engaged in peeling, according to the study. 

[Related: Ivory poaching has triggered a surge in elephants born without tusks.]

Earlier studies show that some African elephants can interpret human pointing gestures and even classify people into different ethnic groups. The team on this study believe that human-derived manipulation behaviors like peeling a banana appear to be unique. “Elephants have truly remarkable trunk skills and that their behavior is shaped by experience,” said Brecht.
The team found it surprising that Pha alone picked up on the behavior and are curious if habits like this are passed down in elephant families. They are now looking into other sophisticated trunk behaviors like tool use.

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While the extinct woolly mammoth and present day elephants may be similar in size and many physical features, scientists are still learning more about what makes the giant elephant ancestors stand apart. The Woolly mammoth went extinct around 4,000 years ago, possibly due to changes in the Earth’s climate, when the vegetation that they survived on became too wet to consume when ice melted, but scientists have uncovered samples of its DNA from specimens preserved in ice and other fossils. 

Scientists found that many of the animal’s trademark features–like large fat deposits and woolly coats–were genetically encoded in the earliest woolly mammoths, but became more defined over 700,000 years of evolution. While woolly mammoths lived in northern parts of America and Eurasia, the specimens in this study came from an area now known as Siberia. The study published April 7 in the journal Current Biology also located a gene with several mutations that may have been responsible for the woolly mammoth’s tiny ears.

[Related: This is the most-complete woolly mammoth ever found in North America.]

“We wanted to know what makes a mammoth a woolly mammoth,” said study co-author and paleogeneticist David Díez-del-Molino of the Centre for Palaeogenetics in Sweden in a statement. “Woolly mammoths have some very characteristic morphological features, like their thick fur and small ears, that you obviously expect based on what frozen specimens look like, but there are also many other adaptations like fat metabolism and cold perception that are not so evident because they’re at the molecular level.”

The team compared 23 Siberian woolly mammoth genomes with 28 modern-day Asian and African elephant genomes. Though woolly mammoths are hypothesized to have been on Earth as long as 2.4 million years ago, their genes had accrued a large number of mutations specifically during those 700,000 years in Siberia. Twenty-two of the woolly mammoths in the study had relatively “modern” genomes, meaning that they had lived within the past 100,000 years. One sample named Chukochya was from an animal that lived roughly 700,000 years ago and is one of the oldest known woolly mammoths scientists have discovered.

[Related: Scientists made a woolly mammoth meatball, but don’t grab your fork yet.]

“Having the Chukochya genome allowed us to identify a number of genes that evolved during the lifespan of the woolly mammoth as a species,” study co-author and evolutionary geneticist Love Dalén from the the Centre for Palaeogenetics said in a statement. “This allows us to study evolution in real time, and we can say these specific mutations are unique to woolly mammoths, and they didn’t exist in its ancestors.”

The team found highly evolved genes related to fat storage and metabolism, like the ones modern-day polar bears and reindeer have, even though those animals are not related to woolly mammoths. According to Díez-del-Molino, this is a sign of convergent evolution–the evolution of two lineages that are similar, but it is not linked to a common ancestor–for the genes in cold-weather adapted mammals. 

[Related: Researchers retraced a woolly mammoth’s steps 17,000 years after it died.]

The relatively large woolly mammoth genome sample size helped the team pinpoint the genes that were common across the species. These genes were likely adaptive–which arise in response to a specific situation–instead of a naturally occurring variation. These genes also may have only been present in the single individual animal studied.

“We found that some of the genes that were previously thought to be special for woolly mammoths are actually variable between mammoths, which means they probably weren’t as important,” said Díez-del-Molino.

Compared with the newer woolly mammoth genomes, the Chukochya genome shared roughly 91.7 percent of the mutations that caused protein-coding changes in the more modern woolly mammoths. This high overlap shows evidence that their thick fur, fat metabolism, and cold-perception abilities were likely already present when the woolly mammoth first diverged from its ancestor the steppe mammoth, between 800,000 to 600,000 years ago.

Older woolly mammoths like Chukochya also likely had larger ears and a different wool type and texture and those traits continue to develop over time. The more modern genomes also had several immune mutations in T cell antigens that were not present in Chukochya. The team believes that these mutations were likely related to developing better immune responses to emerging viruses. 

All the woolly mammoth genomes were from specimens collected in Siberia, but the researchers hope to branch out and compare them with North American specimens. “We showed a couple of years ago that there was gene flow between woolly mammoths and the ancestors of Colombian mammoths, so that’s something that we will need to account for because North American woolly mammoths might have been carrying non-woolly mammoth genes as well,” said Dalén.

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Discovered in 2014, stony coral tissue loss disease (SCTLD) has rapidly spread in the warm waters of the Caribbean. The mysterious ailment that targets hard corals has harmed more than 22 species of stony corals in Florida, the U.S. Virgin Islands, and Puerto Rico. Cases have been confirmed in at least 20 other countries and territories. A 2022 study of the coral species Pseudodiploria strigosa estimated a between 60 and 100 percent mortality rate in the Caribbean alone. 

While the precise cause is unknown, scientists are working to develop effective treatments. In a study published April 6 in the journal Communications Biology, a team of scientists describes the first effective bacterial probiotic for treating and preventing SCTLD. Using a probiotic provides an alternative to using the broad-spectrum antibiotic amoxicillin. So far, using amoxicillin has only been proven to treat the disease, and also runs the risk of promoting antibiotic-resistant bacteria.

[Related: Disease-resistant super corals can save vulnerable reefs.]

Once coral is infected with SCTLD, its colony of polyps can die within only a few weeks. “It just eats the coral tissue away,” Valerie Paul, co-author of the study and a marine biologist and chemical ecologist at the Smithsonian Marine Station at Fort Pierce, Florida, said in a statement. “The living tissue sloughs off and what is left behind is just a white calcium carbonate skeleton.”

While probing how the disease spreads, Paul and a team noticed that some fragments of great star coral (Montastraea cavernosa) quickly developed SCTLD’s characteristic lesions and died, while other pieces didn’t get sick at all. While the precise cause of the disease is unknown, pathogenic bacteria was a suspected culprit in the disease’s progression, since antibiotics were an effective treatment for the disease.

With this in mind, the team collected samples of the naturally occurring, non-pathogenic bacteria present on a pair of disease-resistant great star coral fragments. After testing the samples, the team tried to identify if there were any naturally occurring microorganisms protecting some great star corals from the SCTLD.     

The team used three strains of harmful bacteria from corals that had previously been infected to further test 222 bacterial strains from the disease-resistant corals. While they found that 83 strains that had some antimicrobial activity, a strain named McH1-7 particularly stood out. Further chemical and genetic analysis of McH1-7 confirmed the compounds behind its antibiotic properties and the genes behind those compounds.

[Related: Scientists grow stunning, endangered coral in a lab.]

When they tested McH1-7 with live pieces of great star coral, the tests revealed a final piece of decisive proof: McH1-7 stopped or slowed the progression of the disease in 68.2 percent of the 22 infected coral fragments. It even prevented the sickness from spreading during in all 12 transmission experiments.  

Some next steps for the team are to develop better delivery mechanisms to use this probiotic method at scale in the ocean. The primary method of applying this coral probiotic now is to wrap the coral in plastic to create a makeshift mini aquarium and then inject the helpful bacteria, which would not be feasible on a large scale. It is also not clear if this bacterial strain isolated from the great star coral will have the same effects for other coral species.

To the team, it is still a welcome bit of news, as it could help prevent inadvertently spawning an antibiotic resistant bacteria and help corals in an ever changing climate.  “Between ocean acidification, coral bleaching, pollution and disease there are a lot of ways to kill coral,” Paul said. “We need to do everything we can to help them so they don’t disappear.”

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THE FIRST TIME I had cilantro, I sat in the car with my mother, eating tacos from her favorite spot. As I settled in and took my first bite, I was immediately disgusted and spit it out. After repeated insistence that her food tasted fine and a quick Google search, we deduced that the problem was the cilantro and that I was, sadly, someone to whom it tasted like soap—Dove Sensitive Skin Beauty Bar, to be specific.

“You must get that from yo’ daddy,” she said, laughing. 

The dislike of cilantro is a commonly known food aversion, though it affects only a small section of the population. A 2012 study on young adults in Canada found that, generally, dislike of cilantro ranges between 3 and 21 percent of the population, with varying ethnocultural specificities. Nevertheless, my mama isn’t wrong. There’s a strong chance that I did inherit this distaste for cilantro from my father or someone else in my direct lineage. But before we get into the genetic variations, it’s essential to understand the difference between literal taste and the perception of flavor. 

Taste, scientifically, covers only salt, sweet, sour, bitter, and umami, which are chemical cues picked up by the tongue, explains James N. Palmer, the director of the division of rhinology at the University of Pennsylvania’s School of Medicine. “Flavor is the combination of taste and smell,” he says. “So what people will call taste isn’t really taste: It’s flavor.” 

Our food is broken down with our teeth and the enzymes in our saliva when we eat. Next, the chomped-up bits glide over our papillae, the thousands of little bumps on the tongue, the roof of the mouth, and the throat. Those bumps contain taste buds, which each have between 50 to 100 chemical receptors that identify the five tastes. 

“We use our taste system simply to identify specific chemicals in our food,” says Kathryn Medler, a professor in the University of Buffalo’s biological sciences department. “There are things that we need in our diet, so we prefer them. We eat things that are sweet, salty, or umami [because] those are [nutrients] that we need in our diet in order to be healthy. And we innately avoid sour things, which are going to potentially identify spoiled foods, as well as bitter, which are going to identify potential toxins.” (The cool thing about your taste buds, however, is that you can train them to acquire a taste for sour and bitter flavors.) 

The chewing process also releases odorants. These smells travel up the back of the nasopharynx and into the back part of the nose, resulting in retronasal olfaction, which is how we process odors while consuming food. As we chew, our brains combine these signals to determine the flavor of a food or drink. (Our brains also pick up on mouthfeel–like stringiness or crispiness–as we chew, but that is a separate sensory process.) For instance, Palmer says that steak sauce and chocolate have the same levels of bitterness, sour, and sweet, and that it’s our sense of smell that makes us perceive them as different flavors.

Once the distinction between taste and flavor is clear, it’s easier to understand how DNA affects how we enjoy—or don’t enjoy—certain foods. Our genes influence how we experience flavor, not taste itself. Cilantro will always have a fresh, citrusy smell. But due to a variation in a cluster of olfactory receptor genes that makes them more sensitive to the scents of aldehyde chemicals—found in cilantro and used in soap making—eating cilantro can feel like chewing on a sudsy washrag to some people because the scent of aldehyde is released during chewing.

There are other factors—such as the foods we grew up eating—at play when it comes to why we love or hate certain tastes and flavors. 

Most taste preferences and differences are not necessarily related to genes, says Medler; some can also be related to the cultures or regions we were raised or live in. Take okra, for instance. Medler and I both grew up eating fried okra because we’re Southerners, and we remain very fond of it because it reminds us of home. However, her husband, who grew up in New England, could take it or leave it. “It’s not that he inherently tasted something different than I tasted, but he doesn’t have the positive associations with it,” she explains. 

But both Medler and I lose our affection for okra when it’s cooked in a way that makes it become slimy. The vegetable’s texture is crispier when it’s fried, because frying eliminates most of the gumminess. When it’s included in gumbo or the Nigerian soup obe ila, though, the slippery nature is more pronounced. Enjoying that mouthfeel is typically learned: A friend who grew up eating obe ila loves okra as a stew or fried—in part because it has positive associations for him and because he’s familiar with its textures.

Still, some food experiences, like my soapy-taco debacle, are genetically set in stone. “Everybody’s genetics are slightly different, which means their taste receptors are slightly different, which means [everyone is] going to have different powers in terms of tasting things,” says Palmer. 

“I smile when my patients say, ‘Well, why do things taste different to me than they do to somebody else?’” he continues. “You’re a different height than everybody else. … You have all sorts of other genetic characteristics that differ. So you would expect taste genetics and smell genetics, and therefore flavor genetics, to be different for every person.”

Read more PopSci+ stories. 

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A team of scientists from Australia and Japan didn’t need a super-long fishing pole to catch the deepest fish ever recorded. All it took was a camera, some bait, and a deep-sea submersible support vessel. The team managed to snap a photo of an unknown snailfish species from the genus Pseudoliparis  at a record-breaking 27,349 feet below the ocean’s surface. 

In August 2022, the team boarded the research ship DSSV Pressure Drop for a two-month long expedition to explore three deep trenches of the northern Pacific Ocean: the 23,950 feet deep Ryukyu trench, the 26,246 feet deep Japan trench, and the 30,511 feet deep Izu-Ogasawara trench. The research was part of a 10 year-long study into the deep sea dwelling fish populations. 

[Related: Researchers found signs of human pollution in animals living six miles beneath the sea.]

The small fish was caught on camera in the In the Izu-Ogasawara Trench, south of Japan. This deep sea dweller beats the previous record of 26,830 feet  set in 2017 by a Mariana snailfish found in the Mariana trench near Guam. 

The team also collected two fish in traps a few days later, this time in the Japan trench at a depth of 26,318 meters. These snailfish named Pseudoliparis belyaevi are believed to be the first fish collected from depths greater than 26,000 feet and have only ever been seen at a depth of 25,272 feet back in 2008.

“The Japanese trenches were incredible places to explore; they are so rich in life, even all the way at the bottom,” University of Western Australia marine biologist Alan Jamieson said in a statement. “We have spent over 15 years researching these deep snailfish; there is so much more to them than simply the depth, but the maximum depth they can survive is truly astonishing. In other trenches such as the Mariana Trench, we were finding them at increasingly deeper depths just creeping over that 8,000m [26,246 feet] mark in fewer and fewer numbers, but around Japan they are really quite abundant.”

Jamieson also discovered the previous record winner in 2017 discovery and worked with a team from the Tokyo University of Marine Science and Technology to deploy the baited cameras in the deepest parts of the trenches.

According to the team, despite a large and “somewhat lively” population of fish that dwell at these intense depths, the solitary Pseudoliparis individual that they found was a very small juvenile. Most young snailfish are typically found living at greater depths than the adults, unlike other deep-sea fish. 

“Because there’s nothing else beyond them, the shallow end of the range overlaps with a bunch of other deep-sea fish, so putting juveniles at that end probably means they’ll get eaten,” Jamieson told The Guardian. “When you get down to the mega deep depths, 8,000 plus [meters or [26,246 feet], a lot of them are very, very small.”

[Related: Millions of dead crabs ended up in the deep sea. Scientists still aren’t sure why.]

Almost 10 years ago, Jamieson and his colleagues had hypothesized that it may be biologically impossible for fish to survive at depths greater than this, but after 250 deployments at sea, it seems to be getting closer to becoming a more solid hypothesis.

“The real take-home message for me, is not necessarily that they are living at 8,336m [26,246 feet], but rather we have enough information on this environment to have predicted that these trenches would be where the deepest fish would be,” Jamieson said. “In fact until this expedition, no one had ever seen nor collected a single fish from this entire trench.”

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Wild elephants could be the next animals to join an exclusive list of species that show signs of self-domestication. A study published April 3 in the journal Proceedings of the National Academy of Sciences (PNAS) found that elephant self-domestication may have led to some of their advanced traits, such as mourning their dead, helping sick or injured elephants, and even recognizing themselves in mirrors. 

According to  the self-domestication hypothesis, humans have gone through a process of “selection against aggression,” that was self-induced and not forced.  

“The theory of self-domestication is hard to test,” study co-author and Max Planck Institute evolutionary biologist Limor Raviv said in a statement. “This is because only one other species besides humans has been argued to be self-domesticated: bonobos.”

[Related: A DNA tool designed to solve murders is exposing elephant poachers.]

Raviv and her colleagues looked at how African savannah elephants compared with humans and bonobos on 20 different measures. They found that all three species share some of the same physical features and display the same habits. Elephants play, are social, have a long childhood, and “babysit” for the offspring of other members of their groups. Both bonobos and humans also do this. Additionally, wild African elephants’ have a shortened jawbone, which is a trait shared by domesticated animals such as cats.  They also appear to be able to restrain themselves from being aggressive to others.

Elephants can also learn from each other. Knowledge like what to eat and how to raise their young are socially transmitted, versus being innate like they are in other animals. For example, spiders are born knowing how to spin silk, same goes with birds building nests. Elephants also have a sophisticated and varied communication system. Their extensive vocal repertoire ranges from roars to low-frequency rumbles to trumpets and roars to low-frequency rumbles. Elephants in Kenya even have a different alarm call for bees than they do for humans. 

The team also found several candidate genes associated with domestication in elephants. They compared the genomes of wild elephants with studies of 261 domesticated mammals and created a list of the genes that are frequently associated with domestication. Of the 674 genes that the team says have a high likelihood of being passed down from earlier elephant generations, 79 genes were associated with domestication in other species. This could suggest that domestication can evolve in multiple branches of the mammal evolutionary tree. 

[Related: ‘Zombie genes’ could be why so few elephants die of cancer.]

The team hypothesizes that self-domestication in elephants might be related to their large size and relative strength. “This means that elephants are generally less worried about evading or fighting other animals for their survival,” Raviv said. “This kind of ‘safe environment’ could relax selective pressures for aggression, free cognitive resources, and open up more opportunities for exploration, communication, and play.”

Some scientists remain wary about self-domestication in general and future studies are needed to further test this hypothesis. Melinda Zeder, an emeritus archaeologist and domestication expert at the Smithsonian Institution told Science, “it’s nice to see the correlations with bonobos and humans and the genetic similarities tied to the reduction of aggression,” but she is still skeptical of the self-domestication idea in general. She adds that self-domestication is a “meaningless term that muddies the waters,” and that domestication requires “two to tango,” meaning a domesticator and a domesticate.

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Similar anatomy, not a shared sense of humor, might be key for experiencing deception from a pretty common magic trick. In a new study, a team of psychologists tested a sleight-of-hand trick called the French drop on three species of monkeys with different hand structures. In this trick, an object appears to vanish when a spectator assumes it is taken from one hand by the hidden thumb of the other hand.  

The monkeys without opposable thumbs did not fall for the assumption and were aware of the whereabouts of the treats a magician tried to “make disappear.” But, the monkeys with opposable thumbs were duped. The findings were published April 4 in the journal Current Biology.

[Related: A centuries-old magic trick is helping us make holograms we can feel.]

From the results, it appears that in order to deceive, a conjuror needs a similar anatomy to their audience. Sharing a particular biomechanical ability may be necessary to accurately anticipate and predict the movements of another with the same limbs. This phenomenon turns out to be true even when the apparently accurate predictions end in confusion at the hands of an illusionist. 

“Magicians use intricate techniques to mislead the observer into experiencing the impossible. It is a great way to study blind spots in attention and perception,” study author Elias Garcia-Pelegrin said in a statement. “By investigating how species of primates experience magic, we can understand more about the evolutionary roots of cognitive shortcomings that leave us exposed to the cunning of magicians.”

Garcia-Pelegrin, now a psychology professor at the National University of Singapore, has practiced magic for a decade and conducted these experiments during his PhD work at Cambridge University. 

The French drop is often one of the first tricks budding magicians set out to master. In the trick, a coin is displayed in one hand. The other hand then reaches over and grabs the coin. The palm of the second hand faces inwards, with the magician’s thumb concealed behind fingers. The viewer knows the thumb is lurking and ready to grip, so they assume the coin has been taken when it is no longer visible. Their attention then follows the second hand, only to find it empty. Meanwhile, the magician had secretly dropped the coin into the palm of the original hand.

In this study with monkeys, morsels of food replaced coins and the treats were given as a reward– but only if the monkey guessed the correct hand. Going into the experiment, the team predicted that monkeys with opposable thumbs would act like human audiences and assume that the hidden thumb had grabbed the treat, and then select the incorrect hand.

[Related: Time passes faster for smaller, quicker animals.]

The team repeatedly performed the French drop for 24 monkeys from three species– capuchins, squirrel monkeys, and marmosets. 

The eight capuchin monkeys were tested using peanuts. This species boasts noteable dexterity and uses stone tools to crack open nuts in the wild. Capuchins can also waggle each finger and have opposable thumbs which allow “precision grip” between thumb and forefingers.  They were fooled by the French drop about 81 percent of the time, mostly choosing the empty second hand.

While less dexterous than their capuchin counterparts, squirrel monkeys have limited thumb rotation, but can oppose their thumbs. They are typically familiar with a hidden thumb interacting with fingers, but they cannot cannot perform a precision grip the way capuchins and humans do. The squirrel monkeys were tested with mealworms and were fooled 93 percent of the time. 

Marmosets do not have opposable thumbs and have thumbs that align with their fingers to make five equidistant digits. These are ideal for climbing up thick tree trunks. They were fooled only 6 percent of the time. They chose the hand that initially held a tasty marshmallow was initially placed and stuck with it for this experiment.

The team tried to nullify the tricks by actually completing the hand-to-hand transfers, instead of using misdirection. When this occurred, the capuchins and squirrel monkeys anticipated correctly, while the marmosets missed out on their reward.

As a last step, the team devised their own version of the French drop called the “Power drop”. It utilizes a full fist grab, which is a hand action that all the monkey species could perform to varying degrees. They found that the power drop fooled all of the monkey species the vast majority of the time.

[Related: Monkeys with close friends have friendlier gut bacteria.]

“There is increasing evidence that the same parts of the nervous system used when we perform an action are also activated when we watch that action performed by others,” co-author and Cambridge psychologist Nicola Clayton said in a statement. “This mirroring in our neural motor system might explain why the French drop worked for the capuchins and squirrel monkeys but not for marmosets.”

The team adds that how fingers and thumbs move helps space the way an individual thinks and the assumptions made about the world around us. 

“Our work raises the intriguing possibility that an individual’s inherent physical capability heavily influences their perception, their memory of what they think they saw, and their ability to predict manual movements of those around them,” said Clayton. 

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Roughly one in six people (17.5 percent) around the world are affected by infertility, according to a new report from the World Health Organization (WHO). The report is described as a “first of its kind in a decade,” analyzing infertility data from 1990 through 2021. This  includes data from 133 previously published studies on the prevalence of infertility. 

Infertility is defined as not being able to conceive after one year or more of unprotected sex. The WHO called these new numbers “staggering.” Infertility affects both the male and female reproductive system and can cause significant emotional distress and financial hardship, and is still stigmatized and understudied.

[Related: These urologists are setting the record straight about penises and COVID.]

According to the Centers for Disease Control and Prevention (CDC), roughly one in five married women between 15 and 49 years of age experience infertility.

“The report reveals an important truth: infertility does not discriminate,” said WHO Director General Tedros Adhanom Ghebreyesus in a press release. “The sheer proportion of people affected shows the need to widen access to fertility care.”

The report found little variation in fertility rates across income levels in the new report. Higher-income countries experience infertility rates of roughly 18 percent and low- to medium-income countries see rates of close to 17 percent. 

The report, however, did find differences among how much money people are spending on treatments and how accessible they are. Those in the poorest countries spent a significantly larger proportion of their annual income on one single cycle of in vitro fertilization (IVF) or other fertility care compared to those in wealthier countries. IVF is becoming increasingly unaffordable in the US, and just one cycle of IVF can cost between $10,000 and $25,000, according to reporting from The Washington Post,

Additionally, there was limited data available for countries in Africa and across southern Asia, further emphasizing the unequal access to fertility care and the “persistent need” for better data collection methods in those regions.

While there was some regional variation in infertility at the regional level, the WHO said that the differences were either not substantial or conclusive. The highest lifetime prevalence was found in the Western Pacific (23.2 percent) and the lowest was in the Eastern Mediterranean (10.7 percent).  

[Related: Why birth rates are falling, and why it’s no big deal.]

The report did not determine whether the global infertility rate is increasing or decreasing. The WHO also noted that most of the studies used in this report contained estimates based on female respondents, despite infertility being a condition experienced by both sexes. According to the CDC, hormonal disorders, disruptions to ejaculatory or testicular functions, and genetic disorders may result in infertility in males. Lifestyle factors like smoking and excessive alcohol or drug use, age, and body weight can also undermine the ability to conceive in both sexes.

Asima Ahmad, an endocrinologist and fertility expert who serves as chief medical officer and co-founder of Carrot Fertility, told CNN that the new report shows more people need fertility coverage and access to high-quality healthcare, and that inequities need to be addressed.

“These inequities, I’m not surprised that they exist on a global level, because we already see the inequities in the United States domestically, with how infertility impacts different populations and how some populations have limited access. And even with the access that they finally get, they, for example, will have a lower rate of success or even a higher rate of miscarriage,” said Ahmad, who was not involved in the new WHO report.

Ahmad also cited a lack of access to “clinically vetted evidence-based information” about the causes of infertility and how to recognize and treat it and that access to employer-provided fertility benefits is also a significant barrier to care in the United States.

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Watching a bird leap around on its crooked legs before it takes off into the air is kind of  like turning back the evolutionary clock and watching a theropod dinosaur. Numerous paleontologists believe that theropod group, which includes the spinosaurus, tyrannosaurus rex, and velociraptor, evolved into the birds we see on Earth today. This would make them the only dino-descendants that survived catastrophic extinction 66 million years ago.

Like birds, theropod dinos also laid eggs, and scientists are beginning to fill in evolutionary gaps by studying the shelly remains. A study published April 3 in the journal Proceedings of the National Academy of Sciences (PNAS) examined the calcium carbonate left behind in the eggs of a funky theropod called Troodon and found that the dinosaurs laid four to six eggs in communal nests. 

[Related: Newly found titanosaur eggs reveal dino nurseries once teemed with baby giants.]

Troodon was a carnivorous dinosaur over six feet long that lived in North America about 75 million years ago. It had some bird-like features, particularly its light and hollow bones, two legs, and fully developed feathery wings. However, the dinosaur’s relatively large size kept it from flying, but it likely ran very fast and caught prey in strong claws. 

Troodon females also laid eggs that are more similar in shape to the asymmetric eggs laid by  modern birds than to the round reptile eggs. Their eggs were blue-green colored like other theropod eggs, and they have been found half buried into the ground. The international team of scientists on this study believes that mother Troodons sat and brooded on them.

To learn more, the team examined the calcium carbonate left behind in some well-preserved Troodon eggshells. They used a method developed in 2019 called “dual clumped isotope thermometry.” 

With this technique, they could measure the extent to which heavier isotopes of oxygen and carbon clump together in carbonate minerals. Isotopic clumping is temperature-dependent, and the prevalence of this clumping helped the team determine the temperature at which the carbonates crystallized. The eggshells were likely produced at temperatures of 107 degrees Fahrenheit and then deduced down to 86 degrees, which is very similar to modern birds. 

[Related: A fossilized egg laid by an extinct, human-sized turtle holds a rare jackpot.]

The team then compared  the isotopic compositions of reptile egg shells (alligator, crocodile, and multiple turtle species) with modern birds (chicken, sparrow, wren, emu, kiwi, cassowary, and ostrich) to see if Troodon was closer to either birds or reptiles. Two different isotopic patterns were revealed. The reptile eggshells have isotopic compositions matching the temperature of the surrounding environment, since they are cold-blooded and form their eggs slowly. Birds leave a recognizable non-thermal signature in the isotopic composition, which is evidence of quick eggshell formation. 

“We think this very high production rate is connected to the fact that birds, unlike reptiles, have a single ovary. Since they can produce just one egg at the time, birds have to do it more rapidly,” study author and geochemist from Goethe University Frankfurt in Germany Mattia Tagliavento said in a statement. 

The team compared these results to the remains of Troodon eggshells and did not not detect the isotopic composition which is typical for birds. According to Tagliavento,  “this demonstrates that Troodon formed its eggs in a way more comparable to modern reptiles, and it implies that its reproductive system was still constituted of two ovaries.”

As a last step, the researchers combined their results with existing knowledge about body and eggshell weight and determined that Troodon only produced only four to six eggs per reproductive phase. They found this observation particularly notable because Troodon nests are typically large and have up to 24 eggs, so the team believes that this means they laid their eggs in communal nests. This communal egg nesting behavior is seen in modern day ostriches.  

“Originally, we developed the dual clumped isotope method to accurately reconstruct Earth’s surface temperatures of past geological eras,” study co-author, geochemist, and developer of the new thermometry method Jens Fiebig, said in a statement. “This study demonstrates that our method is not limited to temperature reconstruction, it also presents the opportunity to study how carbonate biomineralization evolved throughout Earth’s history.”

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This article originally appeared in Knowable Magazine.

It’s evening at the northern tip of the Red Sea, in the Gulf of Aqaba, and Tom Shlesinger readies to take a dive. During the day, the seafloor is full of life and color; at night it looks much more alien. Shlesinger is waiting for a phenomenon that occurs once a year for a plethora of coral species, often several nights after the full moon.

Guided by a flashlight, he spots it: coral releasing a colorful bundle of eggs and sperm, tightly packed together. “You’re looking at it and it starts to flow to the surface,” Shlesinger says. “Then you raise your head, and you turn around, and you realize: All the colonies from the same species are doing it just now.”

Some coral species release bundles of a pinkish- purplish color, others release ones that are yellow, green, white or various other hues. “It’s quite a nice, aesthetic sensation,” says Shlesinger, a marine ecologist at Tel Aviv University and the Interuniversity Institute for Marine Sciences in Eilat, Israel, who has witnessed the show during many years of diving. Corals usually spawn in the evening and night within a tight time window of 10 minutes to half an hour. “The timing is so precise, you can set your clock by the time it happens,” Shlesinger says.

Moon-controlled rhythms in marine critters have been observed for centuries. There is calculated guesswork, for example, that in 1492 Christopher Columbus encountered a kind of glowing marine worm engaged in a lunar-timed mating dance, like the “flame of a small candle alternately raised and lowered.” Diverse animals such as sea mussels, corals, polychaete worms and certain fishes are thought to synchronize their reproductive behavior by the moon. The crucial reason is that such animals — for example, over a hundred coral species at the Great Barrier Reef — release their eggs before fertilization takes place, and synchronization maximizes the probability of an encounter between eggs and sperm.

How does it work? That has long been a mystery, but researchers are getting closer to understanding. They have known for at least 15 years that corals, like many other species, contain light-sensitive proteins called cryptochromes, and have recently reported that in the stony coral, Dipsastraea speciosa, a period of darkness between sunset and moonrise appears key for triggering spawning some days later.

Now, with the help of the marine bristle worm Platynereis dumerilii, researchers have begun to tease out the molecular mechanism by which myriad sea species may pay attention to the cycle of the moon.

The bristle worm originally comes from the Bay of Naples but has been reared in laboratories since the 1950s. It is particularly well-suited for such studies, says Kristin Tessmar-Raible, a chronobiologist at the University of Vienna. During its reproductive season, it spawns for a few days after the full moon: The adult worms rise en masse to the water surface at a dark hour, engage in a nuptial dance and release their gametes. After reproduction, the worms burst and die.

The tools the creatures need for such precision timing — down to days of the month, and then down to hours of the day — are akin to what we’d need to arrange a meeting, says Tessmar-Raible. “We integrate different types of timing systems: a watch, a calendar,” she says. In the worm’s case, the requisite timing systems are a daily — or circadian — clock along with another, circalunar clock for its monthly reckoning.

To explore the worm’s timing, Tessmar-Raible’s group began experiments on genes in the worm that carry instructions for making cryptochromes. The group focused specifically on a cryptochrome in bristle worms called L-Cry. To figure out its involvement in synchronized spawning, they used genetic tricks to inactivate the l-cry gene and observe what happened to the worm’s lunar clock. They also carried out experiments to analyze the L-Cry protein.

Though the story is far from complete, the scientists have evidence that the protein plays a key role in something very important: distinguishing sunlight from moonlight. L-Cry is, in effect, “a natural light interpreter,” Tessmar-Raible and coauthors write in a 2023 overview of rhythms in marine creatures in the Annual Review of Marine Science.

The role is a crucial one, because in order to synchronize and spawn on the same night, the creatures need to be able to stay in step with the patterns of the moon on its roughly 29.5-day cycle — from full moon, when the moonlight is bright and lasts all night long, to the dimmer, shorter-duration illuminations as the moon waxes and wanes.

When L-Cry was absent, the scientists found, the worms didn’t discriminate appropriately. The animals synchronized tightly to artificial lunar cycles of light and dark inside the lab — ones in which the “sunlight” was dimmer than the real sun and the “moonlight” was brighter than the real moon. In other words, worms without L-Cry latched onto unrealistic light cycles. In contrast, the normal worms that still made L-Cry protein were more discerning and did a better job of synchronizing their lunar clocks correctly when the nighttime lighting more closely matched that of the bristle worm’s natural environment.

The researchers accrued other evidence, too, that L-Cry is an important player in lunar timekeeping, helping to discern sunlight from moonlight. They purified the L-Cry protein and found that it consists of two protein strands bound together, with each half holding a light-absorbing structure known as a flavin. The sensitivity of each flavin to light is very different. Because of this, the L-Cry can respond to both strong light akin to sunlight and dim light equivalent to moonlight — light over five orders of magnitude of intensity — but with very different consequences.

After four hours of dim “moonlight” exposure, for example, light-induced chemical reactions in the protein — photoreduction — occurred, reaching a maximum after six hours of continuous “moonlight” exposure. Six hours is significant, the scientists note, because the worm would only encounter six hours’ worth of moonlight at times when the moon was full. This therefore would allow the creature to synchronize with monthly lunar cycles and pick the right night on which to spawn. “I find it very exciting that we could describe a protein that can measure moon phases,” says Eva Wolf, a structural biologist at IMB Mainz and Johannes Gutenberg University Mainz, and a collaborator with Tessmar-Raible on the work.

How does the worm know that it’s sensing moonlight, though, and not sunlight? Under moonlight conditions, only one of the two flavins was photoreduced, the scientists found. In bright light, by contrast, both flavin molecules were photoreduced, and very quickly. Furthermore, these two types of L-Cry ended up in different parts of the worm’s cells: the fully photoreduced protein in the cytoplasm, where it was quickly destroyed, and the partly photoreduced L-Cry proteins in the nucleus.

All in all, the situation is akin to having “a highly sensitive ‘low light sensor’ for moonlight detection with a much less sensitive ‘high light sensor’ for sunlight detection,” the authors conclude in a report published in 2022.

Many puzzles remain, of course. For example, though presumably the two distinct fates of the L-Cry molecules transmit different biological signals inside the worm, researchers don’t yet know what they are. And though the L-Cry protein is key for discriminating sunlight from moonlight, other light-sensing molecules must be involved, the scientists say.

In a separate study, the researchers used cameras in the lab to record the burst of swimming activity (the worm’s “nuptial dance”) that occurs when a worm sets out to spawn, and followed it up with genetic experiments. And they confirmed that another molecule is key for the worm to spawn during the right one- to two-hour window — the dark portion of that night between sunset and moonrise — on the designated spawning nights.

Called r-Opsin, the molecule is extremely sensitive to light, the scientists found — about a hundred times more than the melanopsin found in the average human eye. It modifies the worm’s daily clock by acting as a moonrise sensor, the researchers propose (the moon rises successively later each night). The notion is that combining the signal from the r-Opsin sensor with the information from the L-Cry on what kind of light it is allows the worm to pick just the right time on the spawning night to rise to the surface and release its gametes.

Resident timekeepers

As biologists tease apart the timekeepers needed to synchronize activities in so many marine creatures, the questions bubble up. Where, exactly, do these timekeepers reside? In species in which biological clocks have been well studied — such as Drosophila and mice — that central timekeeper is housed in the brain. In the marine bristleworm, clocks exist in its forebrain and peripheral tissues of its trunk. But other creatures, such as corals and sea anemones, don’t even have brains. “Is there a population of neurons that acts as a central clock, or is it much more diffuse? We don’t really know,” says Ann Tarrant, a marine biologist at the Woods Hole Oceanographic Institution who is studying chronobiology of the sea anemone Nematostella vectensis.

Scientists are also interested in knowing what roles are played by microbes that might live with marine creatures. Corals like Acropora, for example, often have algae living symbiotically within their cells. “We know that algae like that also have circadian rhythms,” Tarrant says. “So when you have a coral and an alga together, it’s complicated to know how that works.”

Researchers are worried, too, about the fate of spectacular synchronized events like coral spawning in a light-polluted world. If coral clock mechanisms are similar to the bristle worm’s, how would creatures be able to properly detect the natural full moon? In 2021, researchers reported lab studies demonstrating that light pollution can desynchronize spawning in two coral species — Acropora millepora and Acropora digitifera — found in the Indo-Pacific Ocean.

Shlesinger and his colleague Yossi Loya have seen just this in natural populations, in several coral species in the Red Sea. Reporting in 2019, the scientists compared four years’ worth of spawning observations with data from the same site 30 years earlier. Three of the five species they studied showed spawning asynchrony, leading to fewer — or no — instances of new, small corals on the reef.

Along with artificial light, Shlesinger believes there could be other culprits involved, such as endocrine-disrupting chemical pollutants. He’s working to understand that — and to learn why some species remain unaffected.

Based on his underwater observations to date, Shlesinger believes that about 10 of the 50-odd species he has looked at may be asynchronizing in the Red Sea, the northern portion of which is considered a climate-change refuge for corals and has not experienced mass bleaching events. “I suspect,” he says, “that we will hear of more issues like that in other places in the world, and in more species.”

This article originally appeared in Knowable Magazine, an independent journalistic endeavor from Annual Reviews. Sign up for the newsletter.

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This article was originally featured on Hakai Magazine, an online publication about science and society in coastal ecosystems. Read more stories like this at hakaimagazine.com.

Standing at the foot of a rocky sandstone cliff, biologist Michelle Wainstein inspected her essentials: latex gloves, two long cotton swabs, glass vials, and tubes filled with buffer solution. She placed them in a blue dry bag, rolled it up, and clipped it to a rope wrapped around her waist. It was late afternoon, and she was slick with dirt and sweat from navigating the dense terrain. Her destination lay across the frigid river: two small logs of otter fecal matter resting on a mossy boulder. In she plunged.

The river, the Green-Duwamish in Washington State, trickles out of the Cascade Range and empties 150 kilometers downstream into Puget Sound. The last eight kilometers of the run—known as the lower Duwamish—is so polluted the US Environmental Protection Agency designated it a Superfund site in 2001. For a century, Seattle’s aviation and manufacturing industries routinely dumped waste chemicals like polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) into the water.

“A lot of the river is still really polluted,” says Jamie Hearn, the Superfund program manager at Duwamish River Community Coalition. “The mud is thick and black, and you can smell it.”

Despite the pollution, river otters are everywhere along the waterway, even in the most contaminated areas near the river’s mouth. “I would be walking the docks looking for scat,” remembers Wainstein, “and a couple of times we were lucky enough to see moms with their pups.”

For several weeks in the summer of 2016 and 2017, Wainstein surveyed otter poop she collected from a dozen sites along the river. Comparing contaminant concentrations in the otters’ poop between the river’s industrial and rural zones, Wainstein uncovered the lingering legacy of the region’s toxic past. The poop from otters in the lower Duwamish contained nearly 26 times more PCBs and 10 times more PAHs than poop from their cousins in cleaner water upstream. PCBs disrupt hormonal and neurological processes and affect reproduction in mammals. Both PCBs and PAHs are human carcinogens.

The discovery that otters along the lower Duwamish are living with such high levels of contamination upends a common narrative: that river otters’ return to a once-degraded landscape is a sign that nature is healing.

In Singapore, where smooth-coated otters have reappeared in canals and reservoirs, they have been embraced as new national mascots. “It plays into that rhetoric that government agencies want to project,” says environmental historian Ruizhi Choo, “that we’ve done such a good job that nature is coming back. That image of a city in nature is the new marketing branding.”

In Europe, the once-common Eurasian otter similarly began reappearing in the late 20th century following successful river cleanup campaigns. Conservationist Joe Gaydos at the SeaDoc Society thinks that this phenomenon has helped form the mental link between otters and ecosystem health.

“The number of animals is our first indicator,” Gaydos says. But few seem to ask the next question: are those animals healthy?

As Wainstein’s study suggests, perhaps not. The otters she analyzed in the lower Duwamish have some of the highest concentrations of PCBs and PAHs ever recorded in wild river otters. Previous research has found a correlation between PCB exposure and health risks in wild river otters, including increased bone pathologies, reproductive and immunological disorders, organ abnormalities, and hormonal changes.

Even so, the contamination is not manifesting in physically obvious ways. “They’re not washing up on shore with tumors all over their bodies,” Wainstein says, and neither is their population dwindling. “They’re not setting off this direct alarm with a big change in their ability to survive.”

The otters’ ability to bear such a heavy contaminant burden suggests that a population resurgence alone may not reflect the quality of an environment. They just become as toxic as the environments they inhabit.

However, their localized bathroom habits, mixed diet of fish, crustaceans, and mammals, and persistence in the face of pollution make them useful indicators of environmental contamination.

River otters have played this role before. Following the 1989 Exxon Valdez oil spill, river otters lingered in oil-drenched waterways, allowing scientists like Larry Duffy at the University of Alaska Fairbanks to track the effectiveness of the oil cleanup. In 2014, scientists in Illinois discovered dieldrin in otter organ tissue even though the insecticide had already largely been banned for 30 years. In these cases, the collection of long-term pollution data was made possible by the creatures’ resilience in contaminated waterways. Wainstein wants to similarly use the Green-Duwamish River otters as biomonitors of the Superfund cleanup over the next decade.

Watching workers dismantle a portion of the river’s levied banks to make channels for salmon, Wainstein thinks about the seabirds, shorebirds, and small mammals, like beaver and mink, that were driven out by industrial contamination. She wonders if one day the rumbling machinery dredging up clawfuls of sediment from the riverbed will be taken over by the piercing cries of marbled murrelets, the croaks of tufted puffins, and the bubbling twittering of western snowy plovers.

“How long will it take? And will it actually work?” she says of the cleanup effort. The otters might hold the answer.

This article first appeared in Hakai Magazine and is republished here with permission.

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Real predatory dinosaurs like the infamous Tyrannosaurus rex may have looked quite a bit different than their movie star counterparts—and not just because they had feathers. Theropods like the T. rex may have also had completely different mouths. Instead of a lipless grin and permanently exposed teeth with their upper jaw hanging over the lower jaw like a crocodile, the T. rex may have boasted scaly lips covering up their teeth.

The details of this possible oral makeover are described in a new study published March 30 in the journal Science. An international team of researchers say that these lips were more similar to lizards and their relative, the tuatara. The tuatara, the last survivors of an order of reptiles that thrived during the age of the dinosaurs, is a rare reptile that is found only in New Zealand that can live up to 100 years.

[Related: What are dinosaur feathers like?]

The team examined the tooth structure, wear patterns, and jaw morphology of reptiles from both lipped and lipless groups. They found that the theropod mouth functionality and anatomy actually resembled lizards more than crocodiles. The study says this similarity implies the T. rex had lizard-like oral tissues, with scaly lips covering up their teeth.   

“Paleontologists often like to compare extinct animals to their closest living relatives, but in the case of dinosaurs, their closest relatives have been evolutionarily distinct for hundreds of millions of years and today are incredibly specialized,” study co-author and Canada’s Royal BC Museum paleontology collections manager and researcher Derek Larson, said a statement. “It’s quite remarkable how similar theropod teeth are to monitor lizards. From the smallest dwarf monitor to the Komodo dragon, the teeth function in much the same way. So, monitors can be compared quite favorably with extinct animals like theropod dinosaurs based on this similarity of function, even though they are not closely related.”

Additionally, therapod lips were likely not muscular, as seen in mammals. Most reptiles have lips that cover up teeth, but can’t be moved independently. Humans and mammals can make all sorts of movements with their lips, like curling them into a snarl or posing with “duck face” in a selfie, but reptile lips can’t. 

The study also found that the tooth wear in lipless animals was different from what has been seen in carnivorous dinosaurs. Dinosaurs also had teeth that were no larger than modern lizard teeth when compared to their relative skull size. The teeth were likely not too big to be covered up by scaly lips. 

[Related: Is T. rex really three royal species? Paleontologists cast doubt over new claims.]

Another more lizard-like feature in theropods was the distribution of small holes around the jaws that supply blood and nerves to dinosaur gums and tissues in the mouth. When modeling mouth closure in lipless theropod jaws, the team found that the lower jaw either had to crush jaw-supporting bones or disarticulate the jaw joint to seal the mouth.

“As any dentist will tell you, saliva is important for maintaining the health of your teeth. Teeth that are not covered by lips risk drying out and can be subject to more damage during feeding or fighting, as we see in crocodiles, but not in dinosaurs,” said co-author Kirstin Brink, a vertebrate paleontologist at the University of Manitoba, in a statement.

According to the team, this prehistoric lip debate has roots all the way back to the nineteenth century, when scientists began restoring dinosaur fossils. It became more prominent when blockbuster films like Jurassic Park and documentaries took to the screen and have since become deeply rooted in popular culture. 

“Curiously, there was never a dedicated study or discovery instigating this change and, to a large extent, it probably reflected preference for a new, ferocious-looking aesthetic rather than a shift in scientific thinking,” paleontologist and co-author Mark Witton from the University of Portsmouth, said in a statement. “We’re upending this popular depiction by covering their teeth with lizard-like lips. This means a lot of our favorite dinosaur depictions are incorrect, including the iconic Jurassic Park T. rex.”

This study provides new insights into how paleontologists can reconstruct both the soft tissues and appearance of extinct species, so that scientists can learn more about how they fed, maintained their tooth health, and even more broad patterns in their evolution. 

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While plants can’t chat like people, they don’t just sit in restful silence. Under certain conditions—such as a lack of water or physical damage—plants vibrate and emit sound waves. Typically, those waves are too high-pitched for the human ear and go unnoticed.

But biologists can now hear those sound waves from a distance. Lilach Hadany, a biologist at Tel Aviv University in Israel, and her colleagues even managed to record them. They published their work in the journal Cell today.

Hadany and colleagues’ work is part of a niche but budding field called “plant bioacoustics.” While scientists know plants aren’t just inert decorations in the ecological backdrop— they interact with their surroundings, like releasing chemicals as a defense mechanism—researchers don’t exactly know how plants respond to and produce sounds. Not only could solving this mystery give farmers a new way of tending to their plants, but it might also unlock something wondrous: Plants have senses in a way we never realized.

It’s established that “the sounds emitted by plants are much more prominent after some kind of stress,” says František Baluška, a plant bioacoustics researcher at Bonn University in Germany who wasn’t a part of the new study. But past plant bioacoustics experiments had to listen to plants at a very close distance to measure vibrations. Meanwhile, Hadany and her colleagues managed to pick up plant sounds from across a room.

[Related on PopSci+: Biohacked cyborg plants may help prevent environmental disaster]

The study team first tested out their ideas on tomato and tobacco plants. Some plants were watered regularly, while others were neglected for days—a process that simulated drought-like conditions. Finally, the most unfortunate plants were severed from their roots.

Plants under idyllic conditions seemed to thrive. But the damaged and dehydrated plants did something peculiar: They emitted clicking sounds once every few minutes. 

Of course, if you were to walk through a drought-stricken tomato grove with a machete, chopping every vine you see, you wouldn’t hear a chorus of distressed plants. The plants emit sounds in ultrasound: frequencies too high for the human ear to hear. That’s part of why researchers have only now perceived these clicks.
“Not everybody has the equipment to do ultrasound [or] has the mind to look into these broader frequencies,” says ecologist Daniel Robert, a professor at the University of Bristol in the United Kingdom who wasn’t an author of the paper.

The researchers were able to record similar sounds in other plants deprived of water, including wheat, maize, wine grapes, pincushion cactus, and henbit (a common spring weed in the Northern Hemisphere). 

Biologists think the clicks might come from xylem, the “piping” that transports water and nutrients through a plant. Pressure differences cause air bubbles to enter the fluid. The bubbles grow until they pop—and the burst is the noise picked up by scientists. This process is called cavitation. 

Most people who study cavitation aren’t biologists; they’re typically physicists and engineers. For them, cavitation is often a nuisance. Bursting bubbles can damage pumps, propellers, hydraulic turbines, and other devices that do their work underwater. But, on the other hand, we can put cavitation to work for us: for instance, in ultrasound jewelry cleaners.

Although it’s known cavitation occurs in plants under certain conditions, like when they’re dehydrated, scientists aren’t sure that this process can entirely explain the plant sounds they hear. “There might not be only one mechanism,” says Robert.

The authors speculate that their work could eventually help plant growers, who could listen from a distance and monitor the plants in their greenhouse. To support this potential future,  Hadany and her colleagues trained a machine learning model to break down the sound waves and discern what stress caused a particular sound. Instead of being surprised by wilted greens, this type of tech could give horticulturists a heads-up.

[Related: How to water your plants less but still keep them happy]

Robert suspects that—unlike people—animals might already be able to hear plant sounds. Insects searching for landing spots or places to lay their eggs, for instance, might pick and choose plants by listening in and selecting a plant based on their health.

If there is an observable quality like sound (or light or electric fields) in the wild, then some organisms will evolve to use it, explains Robert. “This is why we have ears,” he says

If that’s the case, perhaps it can work the other way—plants may also respond to sounds. Scientists like Baluška have already shown that plants can “hear” external sounds. For example, research suggests some leaf trichomes react to vibrations from worms chewing on them. And in the laboratory, researchers have seen some plants’ root tips grow through the soil in the direction of incoming sounds.

If that’s the case, some biologists think plants may have more sophisticated “senses” than we perhaps believed.

“Plants definitely must be aware of what is around because they must react every second because the environment is changing all the time,” says Baluška. “They must be able to, somehow, understand the environment.”

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If you give a mouse a video game, scientists can learn quite a bit about the mind. More specifically, mice playing virtual reality video games have helped researchers locate the brain circuitry that is likely responsible for filtering which daily experiences make it into our long-term memory. While there is still far more to investigate, neuroscientists are confident the rodents’ recreational activities have pinpointed key processes and locations involved in memory making.

As detailed in a new report published today in the journal Cell, a team of scientists at Rockefeller University constructed a virtual reality corridor projected in front of mice as they ran atop a rotating Styrofoam ball to control their directions. The test animals received one of three outcomes at the end of their digital journey: unlimited sugar water from a spout, a limited amount of the sweet reward, or a tiny, painless-but-annoying air puff to the face. 

During each run, sensory cues in the form of visual, auditory, and aromatic stimuli prefaced each outcome, gradually teaching the mice what to anticipate at the culmination of each trek down the corridor.

[Related: An experimental AI used human brain waves to regenerate images.]

Once the mice learned which cue anticipated which result, the team tested their ability to remember these external hints over the course of several weeks. During that period, scientists experimented with stimulating and inhibiting the hippocampus and anterior thalamus—while the former is traditionally associated with memory retention, the latter is not. Limiting the abilities of the hippocampus using chemogenetic inhibition showed that the mice had trouble remembering the VR maze’s causes and effects, even in the short-term; doing the same with the anterior thalamus, however, did not. That said, inhibiting the anterior thalamus displayed limitations on mice’s long-term memory abilities, and stimulating this part of the brain actually improved this feat.

The observations proved especially impressive for maze outcomes resulting in only a small amount of sugar water, a reward mice usually forgot more quickly than the unlimited treat access. Researchers found that the thalamus stimulation helped mice remember what should have been a less memorable experience.

[Related: These eight scientists have changed the world with biomedical and global health research.]

“We’ve identified a circuit in the brain that is important for identifying which memories are important and how they are filtered into longer-term storage,” said Rockefeller graduate student Andrew Toader, one of the study’s co-leads, in a statement. “As soon as the mice begin learning a task, the thalamus is performing this selection process and choosing which memories will go on to be stabilized in the cortex long-term.”

Going forward, researchers hope to determine if factors like adrenaline or dopamine aid thalamus in determining memory retention. Additionally, they hope to discover whether or not the memory stabilization process occurs in a short period of time, or continuously over one’s entire life.

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Scientists are only beginning to scratch the surface of understanding the over 7,000 species of bioluminescent organisms on Earth. Animals, such as glowing worms and some crustaceans, use their natural glow for multiple purposes, including attracting both mates and prey. Some species like fireflies and millipedes even use their natural shimmer as a way of scaring off predators. 

These glowing, unique critters are difficult to classify, which limits the amount of research that can be conducted on them. While working on taxonomic research that sought to better classify these shiny organisms, scientists from Japan’s Nagoya University have discovered three new species of bioluminescent polycirrus worms from different parts of Japan. Polycirrus are small, soft-bodied worms that are known for their bright bioluminescence and are typically found in shallow coastal waters of Japan. 

[Related: We finally know why sea pickles glow.]

The three new species are described in a study published March 29 in the journal Royal Society Open Science. 

Taxonomist Naoto Jimi and biochemist Manabu Bessho-Uehara led a research group with members from Japan’s Advanced Industrial Science and Technology, the Olympus Corporation, and Japan Underwater Films Corporation with the goal to organize the species within the genus Polycirrus by their diversity. 

“Initially, the bioluminescent organisms used in our study were believed to belong to a single species, but it turned out that there were actually three new species,” Jimi told PopSci. “This discovery was crucial for improving the accuracy of our research.”

The three new species, newly named Polycirrus onibi, Polycirrus aoandon, and Polycirrus ikeguchii emit blue-violet light and also have unique backstories behind their names. The team turned to Japan’s rich folk tales for the first two species that have a hazy violet-blue bioluminescence. The yokai are a various ghosts, monsters, demons, tricksters, shapeshifters, and other supernatural beings in Japanese folklore. 

Onibi–or “demon fire”– is a will-o’-the-wisp type of yokai that is shaped like a small, floating ball of light. Onibi is believed to lead travelers in mountains and forests astray. The worm Polycirrus onibi is named after this mischievous and ghostly being.  

[Related from PopSci+: Cave worms could hold the secrets to a better life.]

The “aoandon” in the species Polycirrus aoandon means “blue lantern,” which refers to a ghost-like yokai that appears in folklore as a woman wearing a white kimono, but with sharp teeth and horns. The ghost yokai haunts the lanterns in Japanese homes by turning their light an unnatural blue color 

The specimens of Polycirrus ikeguchii were collected in the Notojima region on the west coast of Japan and honors Shinichiro Ikeguchi, the former director of the Notojima Aquarium, who helped the team find the worm specimen.

According to Jimi, the next steps for the team include examining the new species’ behaviors, ecology, and distribution and what drives their bioluminescence on a genetic and molecular level.

“Understanding these luminescence mechanisms contributes to medical and life science research,” said Jimi. “Bioluminescence is a treasure trove of interesting and unusual chemistry. We intend to use our findings to deepen our understanding of the molecular nature of this phenomenon and apply this knowledge to the development of new life sciences technologies.” 

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Windows can be a death trap for birds—after all, their eyesight makes it difficult or impossible to distinguish between glass and clear flying space. Millions of birds crash into windows along their annual migratory paths and the collisions kill somewhere between 365 million to nearly one billion birds in the United States alone each year. 

Volunteers and scientists throughout the years have collected the fallen birds around the country every spring and fall to rehabilitate  injured birds and document the dead.  The bodies contain valuable scientific information, especially when they are compared over time.

[Related: How to help birds avoid crashing into your windows.]

A study published March 28 in the journal Molecular Ecology is helping scientists better understand the relationship between birds and the multiple microbes in their guts by using these unique specimens.

“In humans, the gut microbiome—the collection of bacteria, fungi, and other microbes living in our digestive tracts—is incredibly important to our general health and can even influence our behavior. But scientists are still trying to figure out how significant a role the microbiome has with birds,” co-author Heather Skeen, a biologist and research associate at Chicago’s Field Museum, said in a statement.

Different mammal species tend to have their own signature microbes living in their gut. The microbes help them digest food and fight disease, with evidence that these relationships can go back millions of years. Researchers have been finding that bird microbiomes likely play by a whole different set of rules.

“Bird gut microbiomes don’t seem to be as closely tied to host species, so we want to know what does influence them,” said Skeen. “The goal of this study was to see if bird microbiomes are consistent, or if they change over short time periods.”

Skeen focused on four common species of songbirds called thrushes, but there are dozens of species found throughout Chicago after crashing into the city’s buildings. She took samples from 747 birds over three years and included samples from the thrushes summer breeding grounds in Manitoba in Canada and the Midwestern states of Michigan and Minnesota.

To get inside of the bird bellies, she made a small incision into the abdomen to reach the bird’s intestines and squeezed out what was inside.  She then transferred bird poop from the intestines to specialized filter paper cards that preserve DNA. The genetic material was then sent away for bacteria classification. 

[Related: Puffy unicorn stickers could save millions of migrating birds each year.]

“Analyzing the bacterial DNA present in the poop allowed us to determine exactly what kinds of bacteria were present,” said Skeen. “It turns out, there were about 27,000 different types of bacteria present.”

The team looked for trends in the bacteria present across the whole sample, and found that the different bird species didn’t seem to have their own unique set of microbes—unlike mammals. Instead, time was the clearest link between the birds and the bacteria present in their microbiomes. Gut microbiomes had significant differences in the composition of the bacteria season to season and year to year.

The results suggest that bird microbiomes might have more to do with their environment than the inborn, consistent relationship that is seen in most mammal species. 

Shannon Hackett, associate curator of birds at the Field Museum and a co-author of the paper, says the museum has been scooping birds killed by buildings for 40 years and that this study helps show why museum collections are valuable for research

“At the time, people were like, ‘What the hell are you doing?’ But the fact that he’s been doing this for forty years means we have a unique opportunity to study birds across fairly short periods of time. We have more than 100,000 window-killed birds at this point, it’s an incredibly rich resource,” Hackett said in a statement. “And as technology evolves and new scientists like Heather come up, we broaden what we’re able to do with these resources.”

Some ways to help birds avoid crashing into your windows include using decals and films on them that are invisible to birds while also letting light in, supporting bird-safe buildings, and turning off interior lights at night.

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As the saying goes, “everything’s bigger in Texas.” That extends to one of the state’s famed roadside shopping hubs. Buc-ee’s boasts the world’s largest convenience store, largest car wash, and even the world’s cleanest restrooms among its numerous offerings to motorists traveling the Lone Star and six other states.

The travel center selling everything from jerky to gas grills can now boast that it has a species of ancient beaver named after its smiling cartoon beaver  mascot. A team of researchers at The University of Texas at Austin (UT)  found the fossilized beaver specimen in the school’s collection and named it Anchitheriomys buceei (A. buceei) after Buc-cee’s semi aquatic salesman. 

[Related from PopSci+: Beavers, snails, and elephants are top grads from nature’s college of engineering.]

“Buc-ee’s was founded in 1982, but we may need to rethink our beginnings,” Arch “Beaver” Aplin III, the founder and CEO of Buc-ee’s, said in a statement regarding the company mascot’s place in Texas’ history.

The new species is described in a study published in the March issue of the journal Palaeontologia Electronica.

While driving down a highway in 2020, UT research associate and study co-author Steve May spotted a Buc-ee’s billboard that said “This is Beaver Country.” May thought back to fossils of the beaver fossils he studied at the university’s Texas Vertebrate Paleontology Collections.

“I thought, ‘Yeah, it is beaver country, and it has been for millions of years,’” May said in a statement.

The new paper describes A. buceei and another much smaller species of beaver and provides an overview of beaver occurrences along the Texas Gulf Coast from 15 million to 22 million years ago.

A. buceei roamed Texas about 15 million years ago during the Miocene. A previous study described the “Texas Serengeti” at the time, where large elephant-like animals, alligators, antelopes, and rhinos roamed the state. A. buceei was about 30 percent larger than the modern beavers scurrying across current-day Texas. 

The UT collections includes A. buceei fossils from six sites in Texas, but most of what the researchers could learn about the old beaver comes from a unique partial skull from the eastern town of Burkeville, Texas. That fossil is a fusion of bone and brain cast that formed when sediment naturally seeped into the beaver’s brain cavity. This created a rock replica of the animal’s brain as a specimen fossilized. 

[Related: Wolves and beavers can have magical ecosystem effects—if they have space to thrive.]

The team took high-resolution X-ray images of the skull to get a better look at the small anatomical details of the skull which  helped May and co-author  Matthew Brown, a paleontologist at UT, confirm that the skull belonged to a new species. 

However, this team was not the first to suspect that this was a distinct new species of ancient beaver.  When the skull was originally collected in 1941, a museum curator named Curtis Hesse from Texas A&M University noted that he intended to name it a new species. However, Hesse died in 1945 before he could complete his study and publish his findings. Eighty years later, a team equipped with new technology and more understanding of the fossil record picked right up where Hesse left off.  

“New discoveries in the field capture lots of attention, but equally as valuable are the discoveries made in existing museum collections,” Brown said in a statement. “We know that these opportunities are littered throughout the drawers in these cabinets.”

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An international team of botanists recently discovered two new species of carnivorous plants in the high Andes of southern Ecuador near the Peruvian border. Both species are described in a study published March 24 in the journal PhytoKeys and part of the butterworts group. This group of about 115 species of flowering plants can catch and digest small insects with their sticky leaves. Carnivorous plants use these animals as an additional food source to compensate for any nutritional deficiencies in the soil they’re growing in.

Eating insects gives these plants a competitive advantage over other plants and helps them thrive in challenging habitats like the tropical high Andes Mountains.

[Related: Meet the world’s newest carnivorous plant.]

The team found Pinguicula jimburensis on the shore of a highland lagoon over 11,000 feet high  and Pinguicula ombrophila on a nearly vertical rock face over 9,000 feet high. The lagoon and rock face are within the Amotape-Huancabamba zone, an area with rugged terrain, a varied climate, and known for exceptional biodiversity due to these conditions. The Amotape-Huancabamba zone makes up large portions of southern Ecuador and northern Peru. 

Botanist Álvaro Pérez of the Pontificia Universidad Católica del Ecuador and his team were the first to discover the plants and worked with study co-author and botanist Tilo Henning from the Leibniz Center for Agricultural Landscape Research (ZALF) in Germany.

“As small and scattered as the species’ suitable habitats are, so is the species composition,” Henning said in a statement. “Both of these new species are only known from a single location, where only a few dozens of plant individuals occur in each case.”

Only one population with about 15 mature individuals was discovered, which makes the species quite vulnerable even if it lives in an isolated and difficult-to-access area. According to the team, this limited distribution is common in the Amotape-Huancabamba zone, and there are many more new plant and animal species awaiting discovery.

The discovery of these new species triples the number of butterwort species recorded in Ecuador and the team believes that there are more new species awaiting formal scientific recognition, but finding them has been a race against time.

“The results presented in this study show that the assessment of the Neotropical biodiversity is far from complete. Even in well-known groups such as the carnivorous plants, new taxa are continuously discovered and described, in particular from remote areas that become accessible in the course of the unlimited urban sprawl,” the team wrote in the study. “This is both encouraging and worrying at the same time.”

[Related: Scientists just rediscovered a rare, fungi-eating ‘fairy lantern.’]

They cite relentless urban sprawl and habitat destruction that are a massive threat to biodiversity in general, particularly threatening fragile microhabitats like these plants. While the new species are safe from human interference since they grow in protected areas, human-induced climate change is increasingly affecting carnivorous plants and ecosystems, particularly places like mountain wetlands that rely on regular precipitation.

This reliance on precipitation and waterlogged soil is even reflected in the name Pinguicula ombrophila, which means “rain-loving butterwort,” and more research is needed to study how these rare species will continue to fare as the climate changes.

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For decades, scientists have been studying a South African daisy’s (Gorteria diffusa) deceptive way to attract pollen. It uses its petals to trick male flies into believing the flower is actually a female fly. When a male insect approaches the flower, it jiggles around trying to mate, and typically buzzes off after a few unsuccessful attempts, leaving pollen behind.

In a study published March 23 in the journal Current Biology, scientists have identified three sets of genes that help build the fake fly appearance on the daisy’s petals. To determine what these genes do, the team compared which genes were ‘switched on’ in petals that had fake flies compared to petals without. They then compared the petals to a different type of daisy that produces a simple spot pattern on its petals, to figure out which genes were specifically involved in making the more deceptive fake fly spots.

According to the team, the surprising find is that all three sets of insect lookalike-creating genes already have other functions in the plant. One set moves iron around, one controls when flowers are made, and one makes hairs on the roots grow. 

[Related: Ecologists have declared war on this popular decorative tree.]

“This daisy didn’t evolve a new ‘make a fly’ gene. Instead it did something even cleverer – it brought together existing genes, which already do other things in different parts of the plant, to make a complicated spot on the petals that deceives male flies,” said study co-author and University of Cambridge plant biologist Beverley Glover, in a statement.

To make this work, the ‘iron moving’ genes add iron to the flower petal’s typically reddish-purple pigments, which changes the color to a more fly-like hue of blue-green. The root hair genes create hairs that expand the petal and give it more texture, making  the fake flies appear in different positions on the petals.

According to the team, this method of attracting more male flies to pollinate gives the plant an evolutionary advantage. The daisies grow in a harsh desert environment with a short rainy season, with makes for a  compressed flower producing, pollination, and seeding schedule. There’s intense competition for the plants to attract pollinators, and these fake lady flies help the daisies stand out. 

By evolutionary standards, this daisy is fairly young at 1.5 to two million years old. These fake fly spots were not on the planet’s oldest daisies, so they likely appeared on petals early on in their evolution. 

“We’d expect that something as complex as a fake fly would take a long time to evolve, involving lots of genes and lots of mutations. But actually by bringing together three existing sets of genes it has happened much more quickly,” said study co-author and plant evolution specialist Roman Kellenberger, in a statement. 

[Related: Bees can sense a flower’s electric field—unless fertilizer messes with the buzz.]

The authors add that this is the only example of a flower producing multiple fake flies on top of its petals. Other daisies make simpler spots like those around the petals, but they are not as convincing to real flies. Orchids can also use sexual deception to trick males into mating with its petals.
“It’s almost like evolving a whole new organ in a very short time-frame,” said Kellenberger.“Male flies don’t stay long on flowers with simple spots, but they’re so convinced by these fake flies that they spend extra time trying to mate, and rub off more pollen onto the flower – helping to pollinate it.”

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As winter melts into the spring, flowers start to bloom and  some unique animals also begin to change color. The white-tailed jackrabbit is one of close to 20 species of animals and birds that have evolved to change colors with the seasons. The rabbit is not white all year, changing from its winter white into spring and summer brown with the season. It’s a survival tactic, as darker hued animals stand out to predators in snowy climates. 

A team of researchers from the United States and Portugal sought out to learn more about the genetics involved in these colorful seasonal changes. Their study, published today in the journal Science, details the evolution of winter camouflage in white-tailed jackrabbits. They uncovered how the genes that control this winter color variation could be a key to their survival as the planet warms and snow cover reduces.

[Related: How a peculiar parasitic plant relies on a rare Japanese rabbit.]

“Several members of the research team live and work in the Rocky Mountains, with a close connection to nature and the incredible changes that we are all experiencing year to year in the intensity of extreme weather and climate,” study co-author and ecologist/evolutionary biologist Jeffrey Good from the University of Montana, told PopSci. 

When beginning this research over a decade ago, Good said that a team member discovered a natural history study from 1963 which described more complicated, but intriguing patterns of continuous color variation in a white-tailed jackrabbit population in Colorado.

Study lead author and evolutionary biologist Mafalda Sousa Ferreira from BIOPOLIS-CIBIO at the University of Porto in Portugal was conducting this research as part of her PhD and took a closer look. “This made this part of my PhD project a bit risky,” Sousa Ferreira told PopSci. “If the paper was correct, we could explain something very unique, but if we couldn’t sample the specimens to characterize it, I might have to rethink part of my thesis.” 

With this half a century old clue in tow, they used museum specimens collected over the years to characterize the variations in color. The oldest of their 196 specimens dated back from 1906, sourced  from multiple museums including the Denver Museum of Nature & Science and the American Museum of Natural History in New York. Importantly, they confirmed the study from 1963 on color variation in white-tailed jackrabbits.

“It is very exciting to see something described years earlier materialize like that before your eyes. The high-risk project was actually possible, and eventually successful!” said Sousa Ferreira.

[Related: This hybrid hummingbird’s colorful feathers are a genetic puzzle.]

After categorizing the fur color variation, the team then used genetic sequencing and determined that the jackrabbits’ color variation in winter is primarily determined by three genes (EDNRB, CORIN, and ASIP) that control the production and localization of melanin pigments.

“Fur coat color is determined by pigments that are produced in special cells in the skin (melanocytes). You can think of these cells as pigment factories. How active these factories are—what type of pigment (black and brown, red and yellow) and how much is produced determines the color of hair,” explained Good. 

This process is quite common across mammals and are the same pigments that determine the color and darkness of hair in humans. Jackrabbits can display white, brown, or more intermediate-colored coats depending on what versions they get from their parents. 

After establishing how winter color variation, the environment, and the rabbit’s genetics were related, they combined these results with climate projections on expected snow loss due to climate change.

Surprisingly, they found that rabbit populations with higher variability in their color genes should be well prepared to face snow loss over the next 100 years. These projections indicate that the winter-brown jackrabbits will actually expand their range and could even help rescue the whole species from decline. 

It was a welcome bit of positive news, but the team still cautions that human-caused threats (disease, habitat loss, etc.) put this adaptability in jeopardy and highlights the importance of conservation at the species level.

“The jackrabbits and their coat colors show how understanding and preserving the genetic diversity of a species is just as important, particularly in this rapidly changing natural world,” said Good.

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Swifties, Jerry Garcia’s Deadheads, and Beyoncé’s BeyHive have nothing on Symphony No. 5 in C Minor composer Ludwig van Beethoven’s fandom. The composer is considered one of the most influential musicians of all time and he defied the onset of deafness in his mid-20s and went on to compose 722 works of music, including 16 string quartets, 35 piano sonatas, and 9 symphonies.

Thanks to locks of hair saved by his devoted fans and collaborators, a team of researchers have analyzed his DNA to learn more about the composer’s ailments, almost 200 years after his death. The research is detailed in a study published this week in the journal Current Biology.

Starting at the end of the 1790s, Beethoven started losing his hearing for unknown reasons. In 1802, 25 years before his death, Beethoven asked that his doctor describe his progressive hearing loss to the world so that “as far as possible at least the world will be reconciled to me after my death.” He was also plagued with gastrointestinal ailments and jaundice. 

[Related: Oldest DNA ever sampled paints a lush portrait of a lost Arctic world.]

Beethoven’s desire for a postmortem description of his illness inspired a team of scientists in Europe to pursue this study. Improvements in DNA analysis enabled them to completely sequence a genome from small quantities of very old hair. 

“Our primary goal was to shed light on Beethoven’s health problems, which famously include progressive hearing loss, beginning in his mid- to late-20s and eventually leading to him being functionally deaf by 1818,” said study co-author Johannes Krause from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, in a statement. 

Saving locks of hair of the deceased was a common mourning practice in the Nineteenth Century. In 1804, Treasury Secretary Alexander Hamilton was famously killed in a duel with his political rival Aaron Burr and his wife Eliza clipped a lock of her late husband Alexander Hamilton’s hair and kept it in a ring. 

The team on this study first analyzed the locks of hair attributed to Beethoven, soon finding five others that were confirmed to come from the same European male. They deemed that the five locks were “almost certainly authentic” and then sequenced the composer’s Beethoven’s genome.

While the team was unable to find a definitive cause for the musician’s gastrointestinal problems or deafness, they did find evidence of a hepatitis B infection and a number of significant genetic risk factors for liver disease. These factors together with his overconsumption of alcohol likely contributed to his death at the age of 56. Earlier medical biographers had suggested that Beethoven may have had substantial inherited health troubles, but they did not find any evidence of this in his genome. 

[Related: Autopsies are more important than ever. Here’s what they can tell us.]

They also uncovered another surprise locked within the composer’s DNA. Beethoven’s Y chromosome does not match the Y chromosome of any of the five living relatives who share the same last name and common ancestor on Beethoven’s paternal line. There likely was an extramarital “event” on Beethoven’s father’s side.

“This finding suggests an extrapair paternity event in his paternal line between the conception of Hendrik van Beethoven in Kampenhout, Belgium in c.1572 and the conception of Ludwig van Beethoven seven generations later in 1770, in Bonn, Germany,” said study co-author Tristan Begg, now at the University of Cambridge, in a statement. 

The DNA they found in Beethoven’s hair is genetically most similar to that of people living in the present day state of North Rhine-Westphalia, in the western Germany. 

Additional studies of the hair samples may help clarify when Beethoven was infected with hepatitis B. Further studies of his close relatives might also help to clarify his biological relationship to living descendants of the Beethoven family.

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Everything we’ve learned about dinosaurs essentially comes from fossils. But million-year-old rocks and bones have left a few hulking gaps in our understanding of the prehistoric world. Dinosaur Mysteries digs into the more secretive side of the “terrible lizards,” and all the questions that keep paleontologists up at night.

DINOSAURS DOMINATED EARTH. We all know the trope. The stupendous reptiles were so numerous and unique that they claimed a 150-million-year-long chunk of Earth’s history as the Age of Dinosaurs. 

But talking about a single group of organisms “dominating” the planet is silly. For one thing, the only dinosaurs bobbing in the ocean waves were carcasses, washed out by coastal storms.

Oceans have covered the vast majority of our planet for billions of years and contain more than 96 percent of Earth’s water at present. Dinosaurs, so far as we can tell, never made the sea their home. And paleontologists still don’t know why.

If there’s anything more challenging than understanding why a species evolved a particular way, it’s trying to backtrack on the evolutionary roads it didn’t take. Nature is full of invisible barriers and bottlenecks that open and close based on previous change. We usually don’t perceive these biological constraints until we run into a “Why not?” question. And even then, it can be difficult to distinguish between what’s actually impossible and what simply didn’t happen due to coincidence. In the case of the dinosaurs, though, we have a few clues as to why the seas remained beyond their domain.

For the most part, dinosaurs were atrocious swimmers. But it took decades for paleontologists to figure this out as they waited for the right fossil tracks, analyses of dinosaur bone structure, and computer methods capable of estimating the buoyancy of dinosaurs. During much of the 20th century, when experts insulted living reptiles and dinosaurs alike by characterizing the extinct saurians as dimwitted slowpokes, some paleontologists thought long-necked sauropods like Brachiosaurus could only support their weight in water. They also posited that the “duck-billed” dinosaurs, or hadrosaurids, plunged into lakes when tyrannosaurs stalked too near—the only defense herbivores that weren’t covered in armor or horns could have, apparently. Starting in the 1970s, paleontologists realized that fossilized tracks and other clues about the sauropods and duck-bills indicated they lived in terrestrial environments and weren’t adept in water. Not only that, but the relatively few trace fossils made by swimming dinosaurs—scrapes in the sediment from when they kicked their feet—were created by carnivorous dinosaurs, undercutting the idea that water was a refuge for plant eaters. 

A key dinosaurian trait may have prevented the reptiles from getting cozy in the water. The bony respiratory systems of sauropods and theropods show evidence of a unique set of air sacs connected to the lungs and other parts of the respiratory system. These soft-tissue pockets allowed the creatures to breathe more efficiently than mammals by keeping new air constantly flowing instead of relying on distinct inhales and exhales. (Birds have the same feature, with the added benefit that it keeps their skeletons light by filling bony spaces with air.) But when modeling how these air pockets would have affected dinosaurs’ swimming ability, paleontologists found that even large species would have acted like inflatable pool toys—too light for their size to be stable in the water. Adaptations to a life aquatic usually involve denser bones as a form of natural ballast—too much internal air would make dinosaurs work too hard to stay submerged. So much like us, while some dinosaurs could swim, they certainly weren’t diving neck and neck with the prehistoric sea turtles and plesiosaurs.

The same problem comes up for dinosaurs that were once considered skilled swimmers. The sail-backed, roughly 50-foot-long Spinosaurus has a few anatomical hallmarks associated with dipping and diving: Some of its bones seem extra dense, like those of other semiaquatic animals, and its tail is long and eel-esque, like a giant hitched-on paddle. But recent studies have found that Spinosaurus’ airy skeletal structure would have made it unstable in water too, and that the huge sail would have hampered the dinosaur’s ability to chase after prey while submerged. It’s more likely that the creature, once heralded as the world’s first swimming dinosaur, was more of a wader that plodded through the shallows as it tried to ambush fish. While additional evidence might alter the picture, especially because no one has found anything close to a complete Spinosaurus skeleton, for now the dinosaur most closely associated with the water was less aquatic than an alligator.

In all, after more than two centuries of searching, paleontologists have not identified a single dinosaur fossil that definitely spent most of its life at sea. The few specimens dug up from marine sediments—like the beautifully preserved armored Borealopelta from Alberta—represent dinosaurs that perished inland or along the coasts and were washed out to sea by storms or local flooding. Some became food for sharks and marine reptiles; some formed temporary reefs; and some quickly got buried under rock and soil, preserving their scales in place. But there were plenty of other reptiles in the sea—fish-like ichthyosaurs, long-necked plesiosaurs, and mosasaurs that were the ocean equivalent of Komodo dragons—that prove the dominion of dinosaurs was exaggerated. 

Of course, we know that dinosaurs eventually did wander into the water. For example, about 5 million years after the asteroid impact that ended the Cretaceous, the first ancestors of penguins took the plunge. Today, these water-savvy birds “fly” by flapping their wings underwater and sport a variety of adaptations, from hydrophobic feathers to salt-excreting vessels in their bills, that allow them to spend a great deal of their time in the ocean. But they still reproduce on land, shedding yet another clue to why extinct dinosaurs never hit the deep blue.

So far as we know, all dinosaurs laid eggs—from the very first terrible lizard (“dinosaur” translated into Greek) 243 million years ago to the chickadees bouncing around on the sidewalk in the present. Whereas other marine reptiles repeatedly evolved ways to give birth, likely starting with the soft-shelled eggs that some snakes and lizards retain today, dinosaurs don’t seem to have ever evolved a different capability. Or perhaps they did but were so late to the party that the seas were already full of nimble, sharp-toothed reptiles ready to munch on any awkward dino-paddlers. The ancient world of the dinosaurs was one that ended at the shoreline, leaving plenty of space for other creatures to rule the water.

We hope you enjoyed Riley Black’s column, Dinosaur Mysteries. Check back on PopSci+ in May for the next article.

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Thom van Dooren is a field philosopher at the University of Sydney and the University of Oslo. He is the author of several books, including “Flight Ways: Life and Loss at the Edge of Extinction, “The Wake of Crows: Living and Dying in Shared Worlds,” and “A World in a Shell: Snail Stories for a Time of Extinctions,” from which this article is adapted.

This excerpt was originally featured on MIT Press Reader.

There have been surprisingly few experimental efforts to explore the possible avenues by which Hawai‘i’s snails might have crossed oceans to arrive in their new home. In fact, to date there has been precisely one study on this topic of which I am aware. In 2006, Brenden Holland, a researcher in the biology department at Hawai‘i Pacific University, placed a piece of tree bark with 12 live snails of the species Succinea caduca into a saltwater aquarium. This is one of Hawai‘i’s nonendangered snail species; in fact, it is one of the few species that is found on multiple islands and seems to be doing okay. It is a coastal species, and the individuals enrolled into the study were from populations living as little as 10 meters from the beach. Brenden explained to me: “After heavy rain, they are commonly seen in gullies by the coast so there’s no question that they are going to get washed down pretty frequently.”

The purpose of Brenden’s experiment was to determine whether, when this happens, it might be possible for these snails to move around by sea and successfully establish themselves in new places. The answer, it seems, is yes. Brenden and his colleague Rob Cowie reported that: “After 12 h of immersion, all specimens were alive, indicating that sea water is not immediately lethal and suggesting the potential for rafting between islands on logs and vegetation.”

Why, you might wonder, does this matter? Far from being an abstract, albeit fascinating, scientific curiosity, I am convinced that attending to snail biogeography and evolution is particularly important at our present juncture. Hawai‘i was once home to one of the most diverse assemblages of land snails found anywhere on the planet, over 750 species. Today, however, the vast majority of these species are extinct, and most of those that remain are headed in the same direction. As they disappear from their island homes en masse, my hope is that paying attention to the deep-time processes of snail movement that brought them all here in the first place could help us to understand and appreciate these snails in new ways. As the writer Robert Macfarlane has argued, a deep time perspective can offer “a means not of escaping our troubled present, but rather of re-imagining it; countermanding its quick greeds and furies with older, slower stories of making and unmaking.”

Beyond Hawai‘i’s shores there have been numerous efforts to experimentally explore or otherwise interrogate the puzzle that is the evolution and distribution of island land snails. Charles Darwin, in a letter to Alfred Russel Wallace in 1857, summed up the situation succinctly: “One of the subjects on which I have been experimentising and which cost me much trouble, is the means of distribution of all organic beings found on oceanic islands and any facts on this subject would be most gratefully received: Land-Molluscs are a great perplexity to me.” Or, as he put it in a letter to another correspondent a year earlier: “No facts seem to me so difficult as those connected with the dispersal of land Mollusca.”

“No facts seem to me so difficult as those connected with the dispersal of land Mollusca,” Darwin wrote in 1857.

In an effort to address this perplexity, Darwin submerged land snails in saltwater to discover whether and how long they might survive. Among his other findings was the fact that estivating snails of the species Helix pomatia recovered after 20 days in seawater. The fact that these snails were estivating is important. During these periods snails can create a thin layer of mucus to cover their aperture and prevent them drying out. As long as they are sealed up inside their shells in this way, it seems that many snails can survive being submerged in saltwater for weeks at a time.

Inspired by Darwin, a French study in the 1860s placed 100 land snails of 10 different species in a box with holes and immersed it in seawater. Roughly a quarter of the snails, from six different species, survived for 14 days — which was calculated to be about half the time it would take for an object like a log to float across the Atlantic.

All of these years of submerging snails — of gastropods drowned and survived — have produced one primary, albeit tentative, finding: It is at least possible that land snails are floating around the world to establish themselves in distant places. We just don’t know enough about Hawai‘i’s snails to know how likely a vector this is for their movements; we have a single, short-term study on one of the over 750 known species.

But floating is by no means the only mode of transportation open to snails. In fact, most of the biologists I spoke to were of the view that it probably isn’t the primary way in which they have moved across large distances. While snails have possibly floated around within the Hawaiian archipelago, between islands, it is thought to be unlikely that the first snails to arrive did so in this way: The distances of open ocean are just too vast. But here, things get even stranger, and even less amendable to experimentation.

As we walked along a winding path around the summit of Pu‘u ‘Ōhi‘a on a cool, rainy, afternoon, Brenden Holland and I discussed some of these other potential modes of snail movement across oceans. He explained to me that not all of these possibilities are immediately obvious if we look only at organisms in their current forms. Many species change after arriving on islands; some, for example, undergo processes of “gigantism” or “dwarfism” in which their new environmental conditions lead to a significantly increased or decreased body size. Alongside these kinds of changes, many entirely new species evolve on islands after initial arrival events. In the case of Hawai‘i’s snails, phylogenetic analysis indicates that the vast majority of species evolved in the islands in this way, a single arrival giving rise to multiple new species over a few million years (these analyses compare genetic material to determine how closely related species on different islands are to one another, and in this way piece together their histories of arrival and evolutionary divergence). Some of these new island species will continue to look a great deal like the ancestor that made that initial oceanic crossing; others will not.

As we walked that day, Brenden pointed out to me tiny snails of the species Auriculella diaphana, moving around among the introduced ginger plants. It was these snails he had brought me here to see. He explained that despite their very different appearance, these snails are actually close relatives of the much larger, brightly colored, Achatinella tree snails that have become the poster-children of endangered snail conservation in Hawai‘i. The former is about 7 millimeters in length, the latter about 2 centimeters. But, Brenden told me, Auriculella and Achatinella have a smaller common relative still, and phylogenetic analysis indicates that it is an even more likely candidate for having made the initial trip to the islands. There, among the ginger leaves, we were lucky enough to also encounter some of these tiny beings, members of the subfamily Tornatellidinae.

The Tornatellidinae snails we saw that day, along with some other species within this subfamily, reach a maximum size of about 2 millimeters in length, roughly the size of a grain of rice. But this size difference is more significant than these simple length measurements imply. As Rob Cowie explained to me, the mass of a snail is roughly equivalent to the cube of its length. As such, one of the tiny Tornatellidinae snails might be as much as 1,000 times lighter than its Achatinella brethren. If a minute creature similar to these tiny snails was the ancestor that first made its way to the Hawaiian Islands, then it might have had many other modes of transportation open to it. It might even have arrived by bird.

At some point in the distant past, a tiny snail climbed on board a migratory bird, perhaps a golden plover, as it perched or nested overnight.

In numerous conversations with biologists, again and again I was told with varying degrees of confidence that the most likely answer to the puzzle of Hawai‘i’s snails is that the first ones flew here. Everybody narrated this hypothetical scene a little differently, but the main events remained the same. At some point in the distant past, a tiny snail climbed on board a migratory bird, perhaps a golden plover, as it perched or nested overnight. As snails are nocturnal, it makes sense that they might encounter a perched bird in this way, and that this wayward passenger might then be able to hunker down, deep in the bird’s feathers, sealing itself up. Days or weeks later, having rested through the exhausting crossing, the snail then climbed off the bird in its new home.

I must admit that on first hearing this explanation I was somewhat dubious. This sequence of events just seemed so horribly unlikely. I reminded myself, though, that in the vastness of evolutionary time, “horribly unlikely” is actually pretty decent odds. But as I continued to talk to scientists and read the literature, I discovered an unseen world of surprising snail journeys. For the most part, scientists have not deliberately gone looking for snails on birds, but in a handful of articles published over the last several decades they have nonetheless reported on their accidental encounters with them, usually in the course of routine bird banding or observation. In these cases, it seems, snails have sometimes been present with surprising regularity and abundance.

Across several studies, the snail Vitrina pellucida has been found on a variety of migratory birds in Europe, while Succinea riisei has been found on three different types of birds in North America, with anywhere from one to 10 snails on a single bird. In one particular study, focused on migratory birds in Louisiana, snails were found on three different bird species. The main focus of the research was the woodcock, and it was only on these birds that the researchers really monitored snail presence: “Of the 96 woodcock checked, 11.4% had snails present,” they report. “Of those, the average number of snails per bird was 3.”

In Hawai‘i, there has never been a targeted scientific search for snails on birds, so it is hard to know which species might be climbing on board and with what kinds of frequency. Partway through my research, however, Nori Yeung at the Bishop Museum came across and shared with me a tantalizing snippet from a field notebook. The collecting note was made in 1949 by Yoshio Kondo who was at the time in Nori’s current position as curator of the museum’s malacology collection. There at the top of a grid-lined page, in neat cursive writing, he reported: “a juvenile sooty tern on which were Succinea and Elasmias. Brought bird back. Unfortunately, did not keep shells on bird separate.”

But there is another fascinating, albeit equally speculative, avenue by which tiny snails might move around the globe. They might fly without the aid of birds, blown on leaves and other debris, or just on their own, sealed up in their shells. Indeed, there is significant evidence from sampling, conducted with nets attached to airplanes, that rock particles the size and weight of some of these tiny snails can move around in this way, sometimes being found at altitudes of more than 2,000 meters. Drawing on these findings, some scientists have argued that it is not at all unreasonable to think that snails might travel in similar ways, definitely over shorter distances but perhaps also for transoceanic journeys. At least a couple of the scientists I spoke to, including Brenden and Rob, were holding open the possibility that the progenitors of at least some of Hawai‘i’s snail families may have blown to the islands in this way, perhaps even carried by the winds of a hurricane.

Of course, once a snail species has made that first giant leap across oceans, a range of other options open up for the shorter, inter-island, movements that genetic analysis indicates have taken place at various points in the past. As we have seen, some snails might survive a floating journey between islands. Others, it seems, might be making these briefer trips inside birds: studies in various parts of the world have now shown that a variety of snail species — including as least one species of the Tornatellidinae — can survive passage through avian digestive tracts at a relatively high frequency.

These are, undoubtedly, all rather unreliable ways to travel. For every snail that successfully arrived in a strange new land on a bird or a floating branch, countless millions must have been washed, blown, or flown out to sea without such luck. The odds must be slightly better traveling by bird than log: At least in theory, if you hop onto or into a migratory bird in a forest, you are reasonably likely to be taken to another forest. Of course, for those snails unfortunate enough to be traveling inside the bird, they would have to survive the journey through the digestive system too.

However they travel, snails are largely at the whim of external forces in these movements, subject to what biologists call “passive dispersal.” As Brenden helpfully summed it up for me: “biogeographically, snails are plants” — both groups share many of the same vectors for movement, the latter usually by seed or spore. This is clearly a “system” of island dispersal that can hope to achieve results only with immense periods of time at its disposal. Over millions of years, a few lucky snails made these journeys successfully. We can’t know for certain how many times this happened in the Hawaiian Islands. But by tracing species back to their common ancestors in Hawai‘i and beyond its shores, Brenden and Rob have estimated that things must have worked out for around 20, and likely fewer than 30, intrepid travelers, or groups of travelers, over roughly the past 5 million years (when Kaua‘i, the oldest of the current high islands with suitable snail habitat, formed). All of the rest of Hawai‘i’s incredible gastropod diversity is thought to have evolved in the islands from this small number of common ancestors.

While there is undoubtedly something very “passive” about this dispersal of snails — always at the whim of others, be they birds, storms, or tides, traveling under their steam and direction — this isn’t the whole of the story. Deep evolutionary histories have produced these possibilities. Snails’ modes of passive movement only “work” because they have evolved some remarkable traits for dispersal, survival, and reproduction, across and into isolated new lands: from epiphragms that seal them up inside their shells and sticky eggs that can attach themselves to birds and debris, to hermaphroditism, sperm storage, and self-fertilization which all potentially allow a single snail introduced to a new land to begin reproducing. While not all snails can do all of these things, where these traits are present, they are surely a huge advantage. Millions of years and countless generations of more or less successful journeying have selected for those individuals that survived and established themselves best.

There is a profound kind of evolutionary agency at work here, a creative, experimental, adaptive working-out of living forms with particular capacities and propensities. For the most part, individual snails are indeed relatively passive in all this. They’re not, however, irrelevant. The particular actions of those snails that crawled onto a bird, that opted to seal up their apertures, that safely stored away sperm for future use, mattered profoundly. But neither are snails involved in the more active, sometimes even deliberate, dispersal undertaken by many other animals.

Instead, if we pay attention, snails amaze with their capacity to move so far, to spread so widely, while doing so little. This, it seems to me, is one of the real marvels of snail biogeography. Individuals do not need to exert great effort because natural selection has acted for them, acted on them, acted with them, to produce these beings that are so unexpectedly but uniquely suited to a particular form of deep time travel, drifting. From such a perspective, rather than being any kind of deficiency, the highly successful passivity of snails might be seen as a remarkable evolutionary achievement.

It’s likely that in the history of these islands, on average one successful snail arrival event has taken place every few hundred thousand years.

There is so much more to learn here, so much to learn about not just the vectors but the patterns under which dispersal takes place: Are they laid down by atmospheric and oceanic currents, or by the inherited paths of avian migration? And yet to some extent this must remain a space of uncertainty and even mystery. How can one really study processes of biogeography that take place across such vast periods of time and space? As Brenden reminded me, it’s likely that in the history of these islands, on average one successful snail arrival event has taken place every few hundred thousand years. Put simply, it’s not something that any of us are likely to ever see, let alone study, firsthand.

It is hard to really make sense of the vast, deep-time assemblage of Hawaiian snail life. I imagine it as something like a giant network with strands stretching out across the Pacific Ocean and beyond, extending back over evolutionary and geological time frames. Each strand represents one of hundreds of unique species. Millions of years of unlikely journeys — nestled into a bird’s feathers, or perhaps tucked away in the crevice of a floating log — heading to destinations unknown. Millions of years that have produced these intrepid, even if somewhat unlikely, island dispersers with the reproductive and other adaptations that made these movements possible. These are at least some of the processes that have produced the breathtakingly diverse, utterly unrepeatable assemblage of snail life in Hawai‘i.

To labor to hold this network in mind, however imperfectly, however impossibly, might offer us a glimpse into one of the reasons why these snails matter, and so the significance of what is being lost in their extinction. Doing so might remind us that each of the fragile, fleshy, little individuals of Auriculella diaphana or Achatinella mustelina is not so much a “member” of a species as it is a “participant” in a lineage, one link in a vast, improbable, intergenerational project. These are projects — made up of the lives, histories, and possibilities of diverse snail species — that are today being radically truncated, or simply shorn off, all within the space of a few generations of human life. With them is disappearing countless unique ways of life and the vast evolutionary heritage — to borrow Loren Eiseley’s apt term, the “immense journey” — that they together comprise.

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Artificial light at night can wreak havoc on a number of animals, from confusing moonlight-following sea turtle hatchlings to disrupting the sleep patterns of free-living animals like birds, to even stressing out caterpillars and making them age quicker.

Scientists are continuing to look more at the effects of artificial night light on insect larvae–like caterpillars.  A study published this month in the journal Proceedings of the Royal Society B: Biological Sciences found that even moderate levels of artificial light attract more caterpillar predators and reduce the chance that their larvae grow up into moths. Moths are part of the order lepidoptera that also contains butterflies and skippers ,and their larvae can serve as food for larger prey like birds, wasps, and some small amphibians. 

[Related: The switch to LEDs in Europe is visible from space.]

To test this light theory, scientists from Cornell University placed 552 lifelike caterpillar replicas made of soft clay in a forest in New Hampshire, gluing them to leaves to look as real as possible. They were made from a green clay that mimics the color and size of two moth caterpillars: Noctuidae (owlet moths) and Notodontidae (prominent moths). The marks of predators like birds, other insects, and arthropods can be left in the soft clay if they tried to take a bite of the fake caterpillars. 

Some of the models were placed on experimental lots that had 10 to 15 lux LED lighting, or roughly the brightness of a streetlight. The lights stayed on at night for about seven weeks in June and July 2021.

Of the 552 caterpillars deployed, 521 models were recovered. Almost half (249 fake caterpillars) showed predatory marks from arthropods, during the summer-long nighttime study. Additionally, they found that the rate of caterpillar predation was 27 percent higher on the experimental plots compared with the control areas that didn’t have the LED lighting.

Since the night sky is getting increasingly more polluted with artificial light, this poses another ecological problem for lepidopterans. These creatures already suffer from  threats like  habitat loss, chemical pollutants used in farming, climate change, and increasingly prevalent invasive species, according to the team.

[Related: ‘Skyglow’ is rapidly diminishing our nightly views of the stars.]

These findings are particularly worrisome for caterpillars at a larval stage when they are eating leaves to ensure that they grow into their next stage of development. Study co-author and research ecologist Sara Kaiser told the Cornell Chronicle, “When you turn on a porch light, you suddenly see a bunch of insects outside the door. But when you draw in those arthropod predators by adding light, then what is the impact on developing larvae? Top-down pressure – the possibility of being eaten by something.”
Some simple ways to reduce artificial light are by using smart lighting control to remotely manage any outside lighting, making sure that lights are close to the ground and shielded, and using the lowest intensity lighting possible.

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Starting around seven million years ago, the Thylacosmilus atrox, also known as the “marsupial sabertooth,” prowled South America with canine teeth so large that they reached the top of their skull. The hypercarnivore, meaning it had a diet of at least 70 percent meat, and possibly used its tongue to slurp out the innards of its prey. Thylacosmilus went extinct about 3 million years ago and was a member of Sparassodonta, a group of carnivorous mammals that related to living marsupials.

The 200 pound beast had wide-set eyes like a cow, which are considerably different compared to the forward facing eye sockets of cats.  The strange setup helped the creature see in stereoscopic vision (or 3D).

[Related: Giant wombats the size of small cars once roamed Australia.]

With eyes like this, objects do not overlap sufficiently for the brain to integrate them in three-dimensions. Scientists have long been perplexed as to why the ferocious hunter would evolve such a strange adaptation in its skull. 

Now, a study published March 21 in the journal Communications Biology answers a few questions on how this extinct animal with a unique skull could see and hunt in its ancient world. 

Scientists from Argentina and the US used CT scanning and 3D virtual reconstructions to assess how the nasal cavities were organized in both modern and fossilized mammals.  The scans and reconstructions enabled the team to compare Thylacosmilus’ visual system with other carnivores or other mammals in general and study orbital convergence. This is the way the eyes move together and point inward when they look at objects that are close by. 

Thylacosmilus had an orbital convergence value as low as 35 degrees, which is pretty extreme compared to that of a typical predator at around 65 degrees. 

“Thylacosmilus was able to compensate for having its eyes on the side of its head by sticking its orbits out somewhat and orienting them almost vertically, to increase visual field overlap as much as possible,” said co-author Analia M. Forasiepi, from Instituto Argentino de Nivología, Glaciología, y Ciencias Ambientales (INAGLIA) and a researcher at the Argentinian science and research agency, in a statement. “Even though its orbits were not favorably positioned for 3D vision, it could achieve about 70 percent of visual field overlap—evidently, enough to make it a successful active predator.”

According to the team, how Thylacosmilus was able to compensate for low orbital convergence appears to be the key to understanding how this extinct marsuipial’s skull was put together. The growth patterns in their canines during early stages of development would have moved the eye sockets away from the face, resulting in the wide-set eyes seen in adults. 

“You can’t understand cranial organization in Thylacosmilus without first confronting those enormous canines,” said Charlène Gaillard, a Ph.D. student also at INAGLIA and study co-author, in a statement. “They weren’t just large; they were ever-growing, to such an extent that the roots of the canines continued over the tops of their skulls. This had consequences, one of which was that no room was available for the orbits in the usual carnivore position on the front of the face.”

[Related: Koalas use their noses to find friends and avoid enemies.]

The strange placement of the eye sockets was not the only modification that Thylacosmilus developed to accommodate its enormous canines. Since their eyes are much closer to their chewing muscles, these muscles risk getting deformed while eating. The eyes on the side of the skull also brings them closer to the mouth’s chewing muscles, possibly resulting in a deformation of the mouth muscles. Some mammals, including primates and Thylacosmilus, have developed a bony structure that closes off the eye sockets from the side as a way to control this. 

Now, a new question remains—why would the animal develop huge, constantly growing teeth that required its whole skull to be re-engineered? 

“It might have made predation easier in some unknown way,” said Gaillard. “The canines of Thylacosmilus did not wear down, like the incisors of rodents. Instead, they just seem to have continued growing at the root, eventually extending almost to the rear of the skull.”

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The United Nations’ Intergovernmental Panel on Climate Change (IPCC) released their Sixth Synthesis Report on climate change (AR6), following a week-long meeting in Switzerland. The up to 50 page-long report finds that there is still a chance for humanity to avoid the worst of climate change’s future harms, but it might be our last chance.

“This report can be summarized as a message of hope,” said IPCC Chair Hoesung Lee in a press conference. “This report clearly emphasizes that we do have technology and know how and tools to solve climate problems.” These are the major takeaways from the new report.

We must reduce fossil fuel emissions by 2035

According to the report, carbon pollution and fossil fuel use must be reduced by nearly two-thirds by 2035 in order to stave off the worst effects of climate change. More than 100 years of burning fossil fuels, in addition to unequal and unsustainable energy and land use ,has led to global warming of 2°F above pre-industrial levels. This increase has caused more frequent and intense extreme weather events, and makes the world more dangerous for life in every region of the planet.

[Related: Here’s how global warming will change your town’s weather by 2080.]

United Nations Secretary-General Antonio Guterres called for an end to all new fossil fuel exploration by 2040. Additionally, he called for carbon-free electricity generation in the developed world as early as 2035.

“Humanity is on thin ice — and that ice is melting fast,” Guterres said. “Our world needs climate action on all fronts — everything, everywhere, all at once.”

The report also says that investment and adaptation measures to climate change must be ramped up to reach the goal of the 2015 Paris climate agreement of limiting the amount of warming to 2.7°F.  The world has already warmed 2°F, making it a few tenths of a degree away from some of the most dire effects of climate change. Earlier IPCC reports detailed the harms at this level of warming, which includes worsened storms, famine, and sea level rise. 

Adaptation and mitigation has huge net benefits

AR6 also outlines that the solutions lie in climate resistant development, which provide wider benefits to society as a whole. Better access to clean energy and technology can improve health outcomes, particularly for women and children. Low-carbon forms of transportation (walking, cycling, public transit, etc.) can improve air quality. The economic benefits from improving people’s health by reducing greenhouse gas emissions would be roughly the same or possibly greater than the costs it will take to reduce emissions. 

[Related: Pandemic shipping took a heavy toll on the climate.]

The panelists at the press conference stressed how actions this decade are crucial to ensure a safe future and that this report points to the co-benefits from acting now will have more than the IPCC’s report from 2014 (AR5).  

Political and financial will is key

The report also highlights the imperative role of financing adaptation and mitigation measures. The authors found that while government’s are key to enforcing policy, the financial sector must play their role too. 

“At the core, the financial system needs to be able to respond to the challenges ahead,” said Amjad Abdulla, IPCC Vice Chair. “There’s plenty of financing that’s available for multiple reasons and multiple activities, but our underlying assessment suggests, in that context, the investments that need to take place in both climate adaptation and mitigation needs to rise by three to six times at least.”

The report and press conference focused on the disparity between rich and developing nations, as wealthier nations cause more carbon dioxide emissions, while poorer countries get hit harder by extreme weather. The report calls for an increase in financial help for developing countries to adapt to a warmer world and switch to environmentally sustainable forms of energy. Following the UN’s Climate Conference in November 2022, financial pledges were made for a damage and compensation fund for developing countries. 

[Related: 3 of the the biggest climate decisions from COP27.]

The report is based on data from a few years ago, and does not take into account fossil fuel projects that are already in development and comes one week after President Biden approved the massive Willow oil project in Alaska. This new site could produce up to 180,000 barrels of oil a day and is seen by some political columnists and Democrats as a betrayal by President Biden. 

“The Synthesis Report makes clear that we need swift and bold action to have any chance of averting the worst of the climate crisis. Under President Biden’s leadership, the U.S. has made historic progress in building an equitable clean energy economy, including the passage of the Inflation Reduction Act,” said Jill Tauber, EarthJustice Vice President of Litigation for Climate & Energy, in a press release. “However, the administration is undermining its own gains by greenlighting carbon bombs, like the Willow project, which would lock us into decades of more greenhouse gas emissions.”

In tandem with the reports findings, the World Resources Institute also points to fact that it is not too late to work to ensure a better future for the planet. 

“Despite their dire warnings, the IPCC offers reasons to be hopeful,” said World Resources Institute President and CEO Ani Dasgupta, in a press release. “The report shows a narrow path to secure a livable future if we rapidly correct course. This involves deep emission reductions from every sector of the economy, as well as much greater investments to build resilience to climate impacts and support for people facing unavoidable climate losses and damage. 

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Around a decade ago, Kobe University biologist Kenji Suetsugu took a research trip to Japan’s Chiba Prefecture on the eastern outskirts of Tokyo. While there, pops of vivid colored flowers rising out from the green and brown grassland caught his eye.

“Its vibrant colors immediately caught my attention. I remember being struck by its unique rosy pink petals that bear a striking resemblance to glasswork,” Suetsugu tells PopSci in an email. 

[Related: This incredibly rare orchid survives by making male beetles horny.]

What he saw was actually an undiscovered species of orchid, a rarity in a country whose plant species have been extensively studied and classified.  The discovery of the delicate, elegant, pink-petaled Spiranthes hachijoensis (S. hachijoensis) is detailed in a new study co-authored by Suetsugu and published on March 17 in the Journal of Plant Science. 

S. hachijoensis is actually found in many common places in Japan like parks, lawns, and gardens,  but the striking plant was not named.  Scientists believed that all the Spiranthes on the Japanese mainland were actually one species. The blooms of S. hachijoensis are pink, purple, and white and its petals are about 0.1 to 0.2 inches long. 

Additional specimens have been collected in Japan and as far away as Taiwan and Laos. “After collecting some samples, we took the flowers back to the laboratory and dissected them. We noticed that the morphology was different from other plants we had studied,” Suetsugu explains. 

They analyzed the samples DNA and reproductive biology and found that this cryptic species had genetic differences from other orchids in the genus at the molecular level. S. hachijoensis has a smooth stem instead of the typically hairy stem of another lookalike species named Spiranthes australis. While the new species grows alongside S. australis, it blooms about a month later, leading to reproductive isolation between the two distinct plant species. 

The orchid species that make up the Spiranthes genus are commonly called ladies’ tresses, due to their resemblance to locks of hair. Their dainty, bell shaped flowers bloom  in a variety of colors from yellow to purple to pink or white, and are typically grown from a hairy central stem in a spiral. There are roughly 50 Spiranthes found in tropical or temperate regions of North and South America, Eurasia, and Australia. According to Suetsugu, Spiranthes have been known to Japan for centuries and is the country’s most familiar orchid. It is even featured in Manyoshu, or “Collection of Ten Thousand Leaves,” Japan’s oldest anthology of poetry dating back to 750 CE.

[Related: How a peculiar parasitic plant relies on a rare Japanese rabbit.]

The team will continue to keep studying S. hachijoensis to better understand its DNA, ecology, evolutionary history, and conservation status. While orchids are a very prolific plant with roughly 28,000 known species around the world, habitat loss has endangered the beautiful and ephemeral flowers.

“Discovering a new species is not only exciting, but also important for our understanding of biodiversity and for conservation efforts,” says Suetsugu. “The discovery of this new species hiding in mundane places demonstrates the need for persistent exploration even in seemingly unremarkable places. I think it’s a discovery that reminds us that there is still an unknown world in nature that we come into contact with on a daily basis.”

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Over 60,000 years ago, an eagle relative with an almost 10 foot wingspan stalked the skies over southern Australia. Dynatoaetus gaffae (Gaff’s powerful eagle) had talons that could even snatch a koala or small kangaroo for dinner. The massive bird of prey was likely the largest continental eagle the world had ever seen. 

A study published March 16 in the Journal of Ornithology details how a team of fossil hunters from Flinders University in Australia put together this bird’s story. Four large fossilized bones were collected in Mairs Cave southern Australia’s Flinders Ranges  as far back as 1956 and 1969. The authors found an additional 28 bones scattered among the boulders in the site whoch helped them create a better picture of this giant extinct bird. 

[Related: This dragon-like reptile once soared over Australia.]

This now extinct raptor is closely related to Old World vultures that prowled Africa and Asia during the Pleistocene. In today’s fauna, its closest relative is likely the critically endangered monkey-munching Philippine Eagle. During the late Pleistocene Epoch, when giant megafauna like the mammoth roamed the Earth and ice sheets and glaciers were growing, Dynatoaetuswas likely the top avian predator on the planet. 

“It’s often been noted how few large land predators Australia had back then, so Dynatoaetus helps fill that gap,” said study author and Flinders University paleontologist Ellen Mather, in a statement.  “This discovery reveals that this incredible family of birds was once much more diverse in Australia, and that raptors were also impacted by the mass extinction that wiped out most of Australia’s megafauna.”

Dynatoaetus and another recently described smaller bird named Cryptogyps represent a new genera of raptors that are unique to Australia. 

“[Dynatoaetus] was humongous. Larger than any other eagle from other continents, and almost as large as the world’s largest eagles once found on the islands of New Zealand and Cuba, including the whopping extinct 13kg [28 pound] Haast’s eagle of New Zealand,” said Trevor Worthy, a study co-author and paleontologist at Flinders University, in a statement. 

[Related: Giant wombats the size of small cars once roamed Australia.]

Dynatoaetus also coexisted with the Wedge-tailed Eagle, a species that currently lives in Australia. The team says that this has interesting implications.

“Given that the Australian birds of prey used to be more diverse, it could mean that the Wedge-tailed Eagle in the past was more limited in where it lived and what it ate,” said Mather. “Otherwise, it would have been directly competing against the giant Dynatoaetus for those resources.”

Most of Australia’s eagles and vultures like the Dynatoaetus went extinct about 50,000 years ago, along with most of the continents’s megafauna.  One 2020 study found that a possible explanation is extreme environmental change and deterioration (loss of water, increased burning of trees and grass, etc.) that wiped out at least 13 super-sized megafauna species, including the world’s largest wombats and kangaroos.

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Using microscopes to observe living things has been one of the most powerful ways to understand how biology works, at least since Dutch naturalist Antonie van Leeuwenhoek first zoomed in on bacteria in the 1600s. Today, high-magnification images can help design new medical tools, enrich our understanding of diseases, and explain how embryos develop. And, as shown by the 2023 winners from the MIT Koch Institute Image Awards, they can be works of art, too.

The above image shows Arabidopsis thaliana pollen with proteins removed from their nuclear lamina, a membrane of dense filaments that provides structure to cells. Humans who lack lamina (a mutation seen in some skeletal and muscular conditions) generally cannot survive for more than 20 years, according to the biologists at MIT’s Whitehead Institute and the Koch Institute who took this image. They stuck the grains to carbon tape and imaged them with a Zeiss Crossbeam microscope. Without these proteins, pollen also appear misshapen—underscoring the importance of this meshwork for plants as well.

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