Number of fish species at risk of extinction fivefold higher than previous estimates, according to a new prediction

Researchers predict that 12.7% of marine teleost fish species are at risk of extinction, up fivefold from the International Union for Conservation of Nature's prior estimate of 2.5%. Nicolas Loiseau and Nicolas Mouquet from the MARBEC Unit (the Marine Biodiversity, Exploitation and Conservation Unit) in Montpellier, France, and colleagues report these findings in a study published August 29th in the open-access journal PLOS Biology. Their report includes nearly 5,000 species that did not receive an IUCN conservation status due to insufficient data.

The IUCN's Red List of Threatened Species tracks more than 150,000 species to guide global conservation efforts on behalf of the most threatened.

However, 38% of marine fish species (or 4,992 species at the time of this research) are considered Data-Deficient and do not receive an official conservation status or the associated protections.

To better direct conservation efforts toward the species that need them, Loiseau and colleagues combined a machine learning model with an artificial neural network to predict the extinction risks of Data-Deficient species.

The models were trained on occurrence data, biological traits, taxonomy and human uses from 13,195 species.

They categorized 78.5% of the 4,992 species as Non-Threatened or Threatened (which includes Critically Endangered, Endangered and Vulnerable IUCN categories). Predicted Threatened species increased fivefold (from 334 to 1,671) and predicted Non-Threatened species increased by a third (from 7,869 to 10,451).

Predicted Threatened species tended to have a small geographic range, large body size and low growth rate.

The extinction risk was also correlated with shallow habitats.

The South China Sea, the Philippine and Celebes Seas and the west coasts of Australia and North America emerged as hotspots for predicted Threatened species.

The researchers recommend increased research and conservation efforts in these areas.

The researchers observed "a marked change in conservation priority ranking after species IUCN predictions," recommending that the Pacific Islands and Southern Hemisphere's polar and subpolar regions be prioritized to account for emerging at-risk species.

Many species that remained Data-Deficient occur in the Coral Triangle, indicating that additional research is needed there.

The researchers note that models cannot replace direct evaluations of at-risk species but AI offers a unique opportunity to provide a rapid, extensive and cost-effective evaluation of extinction risk of species.

Read more at Science Daily

Tracking down the asteroid that sealed the fate of the dinosaurs

Geoscientists from the University of Cologne have led an international study to determine the origin of the huge piece of rock that hit the Earth around 66 million years ago and permanently changed the climate. The scientists analysed samples of the rock layer that marks the boundary between the Cretaceous and Paleogene periods. This period also saw the last major mass extinction event on Earth, in which around 70 percent of all animal species became extinct. The results of the study published in Science indicate that the asteroid formed outside Jupiter's orbit during the early development of our solar system.

According to a widely accepted theory, the mass extinction at the Cretaceous-Paleogene boundary was triggered by the impact of an asteroid at least 10 kilometres in diameter near Chicxulub on the Yucatán Peninsula in Mexico.

On impact, the asteroid and large quantities of earth rock vaporized.

Fine dust particles spread into the stratosphere and obscured the sun.

This led to dramatic changes in the living conditions on the planet and brought photosynthetic activity to a halt for several years.

The dust particles released by the impact formed a layer of sediment around the entire globe.

This is why the Cretaceous-Paleogene boundary can be identified and sampled in many places on Earth.

It contains high concentrations of platinum-group metals, which come from the asteroid and are otherwise extremely rare in the rock that forms the Earth's crust.

By analysing the isotopic composition of the platinum metal ruthenium in the cleanroom laboratory of the University of Cologne's Institute of Geology and Mineralogy, the scientists discovered that the asteroid originally came from the outer solar system.

"The asteroid's composition is consistent with that of carbonaceous asteroids that formed outside of Jupiter's orbit during the formation of the solar system," said Dr Mario Fischer-Gödde, first author of the study.

The ruthenium isotope compositions were also determined for other craters and impact structures of different ages on Earth for comparison. This data shows that within the last 500 million years, almost exclusively fragments of S-type asteroids have hit the Earth. In contrast to the impact at the Cretaceous-Paleogene boundary, these asteroids originate from the inner solar system. Well over 80 percent of all asteroid fragments that hit the Earth in the form of meteorites come from the inner solar system. Professor Dr Carsten Münker, co-author of the study, added: "We found that the impact of an asteroid like the one at Chicxulub is a very rare and unique event in geological time. The fate of the dinosaurs and many other species was sealed by this projectile from the outer reaches of the solar system."

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New study reveals insight into which animals are most vulnerable to extinction due to climate change

In a new study, researchers have used the fossil record to better understand what factors make animals more vulnerable to extinction from climate change. The results could help to identify species most at risk today from human-driven climate change. The findings have been published today in the journal Science.

Past climate change (often caused by natural changes in greenhouse gases due to volcanic activity) has been responsible for countless species' extinctions during the history of life on Earth. But, to date, it has not been clear what factors cause species to be more or less resilient to such change, and how the magnitude of climate change affects extinction risk.

Led by researchers at the University of Oxford, this new study sought to answer this question by analysing the fossil record for marine invertebrates (such as sea urchins, snails, and shellfish) over the past 485 million years. Marine invertebrates have a rich and well-studied fossil record, making it possible to identify when, and potentially why, species become extinct.

Using over 290,000 fossil records covering more than 9,200 genera, the researchers collated a dataset of key traits that may affect resilience to extinction, including traits not studied in depth previously, such as preferred temperature. This trait information was integrated with climate simulation data to develop a model to understand which factors were most important in determining the risk of extinction during climate change.

Key findings:

• The authors found that species exposed to greater climate change were more likely to become extinct. In particular, species that experienced temperature changes of 7°C or more across geological stages were significantly more vulnerable to extinction.
• The authors also found that species occupying climatic extremes (for instance in polar regions) were disproportionately vulnerable to extinction, and animals that could only live in a narrow range of temperatures (especially ranges less than 15°C) were significantly more likely to become extinct.
• However, geographic range size was the strongest predictor of extinction risk. Species with larger geographic ranges were significantly less likely to go extinct. Body size was also important, with smaller-bodied species more likely to become extinct.
• All of the traits studied had a cumulative impact on extinction risk. For instance, species with both small geographic ranges and narrow thermal ranges were even more susceptible to extinction than species that had only one of these traits.

Cooper Malanoski (Department of Earth Sciences, University of Oxford), first author of the study, said: 'Our study revealed that geographic range was the strongest predictor of extinction risk for marine invertebrates, but that the magnitude of climate change is also an important predictor of extinction, which has implications for biodiversity today in the face of climate change.'

With current human-driven climate change already pushing many species up to and beyond the brink of extinction, these results could help identify the animals that are most at risk, and inform strategies to protect them.

Lead author Professor Erin Saupe (Department of Earth Sciences, University of Oxford) said: 'The evidence from the geological past suggests that global biodiversity faces a harrowing future, given projected climate change estimates. In particular, our model suggests that species with restricted thermal ranges of less than 15°C, living in the poles or tropics, are likely to be at the greatest risk of extinction. However, if the localized climate change is large enough, it could lead to significant extinction globally, potentially pushing us closer to a sixth mass extinction.'

According to the research team, future work should explore how climate change interacts with other potential drivers of extinction, such as ocean acidification and anoxia (where seawater becomes depleted of oxygen).

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World's first successful embryo transfer in rhinos paves the way for saving the northern white rhinos from extinction

BioRescue, an international consortium of scientists and conservationists, succeeded in achieving the world's first pregnancy of a rhinoceros after an embryo transfer. The southern white rhino embryo was produced in vitro from collected egg cells and sperm and transferred into a southern white rhino surrogate mother at the Ol Pejeta Conservancy in Kenya on September 24, 2023. The BioRescue team confirmed a pregnancy of 70 days with a well-developed 6.4 cm long male embryo. The successful embryo transfer and pregnancy are a proof of concept and allow to now safely move to the transfer of northern white rhino embryos -- a cornerstone in the mission to save the northern white rhino from extinction.

On September 24, 2023, the BioRescue scientists and veterinarians, led by the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW), transferred two southern white rhino embryos into Curra, a southern white rhinoceros, selected as a surrogate mother at the Ol Pejeta Conservancy in Kenya. The oocytes used in producing the embryos were retrieved from Elenore, a southern white rhinoceros living in the Pairi Daiza Zoo in Belgium. The sperm used for fertilisation originated from the male Athos from the Zoo Salzburg in Hellbrunn, Austria. The oocytes from Elenore were fertilised in vitro by intracytoplasmic sperm injection (ICSI) and developed into blastoscysts at Avantea's laboratories in Cremona, Italy. For the embryo transfer in Kenya, the BioRescue scientists transferred two embryos to increase the chance of a successful outcome.

So far, the BioRescue team has performed 13 embryo transfers in rhinoceroses, three in Kenya and ten in Europe. Previously, an embryo transfer, which is a widely used technique in domestic species, has never been attempted in rhinos. BioRescue scientists developed the necessary techniques, by building on decades of their own research.

Currently, there are only two northern white rhinos left in the world: The female Najin and her daughter Fatu. Additionally, living cells from 12 different northern white rhino individuals are stored in liquid nitrogen. The last two females currently live in Kenya, at Ol Pejeta Conservancy, where they are guarded and cared for day and night. Since 2019, the BioRescue conservation science programme produced and cryopreserved 30 northern white rhino embryos. These are currently stored in liquid nitrogen at minus 196 degrees Celsius in Berlin, Germany, and Cremona, Italy, awaiting embryo transfer into southern white rhino surrogate mothers. The successful transfer of a southern white rhino embryo is a proof of concept that allows to take this crucial step -- an embryo transfer with a northern white rhino embryo -- for the first time.

The embryo transfer in this subspecies is entirely new ground as a veterinary and scientific procedure, and all protocols, methods and pieces of equipment had to be newly developed from scratch. As it is the established routine with all BioRescue procedures, the embryo transfers are accompanied by an ethical assessment conducted by Padua University. This was also the case in September, when all participants of the embryo transfer filled out a questionnaire that proposed any possible scenarios during the procedure, and attendant risks to animals and participants.

The vasectomised, sterile teaser bull Ouwan mated with Curra on September 17 and 18, signalling the ideal timing for the embryo transfer, which took place on September 24. After the procedure until November 2023, Curra was monitored on a daily basis in the enclosure at the Ol Pejeta Conservancy. During this period, Ouwan showed no further interest in Curra, a first sign of a successful embryo transfer resulting in pregnancy. The BioRescue team was scheduled for November 28 to perform a pregnancy check in Curra, but the teaser bull Ouwan was found dead on November 22 and Curra was found dead on November 25. Apparently, extremely heavy rains led to a flooding of the surrogate enclosure and set free dormant clostridianbacteria spores. The dissection of the animals revealed a severe systemic infection by a clostridian bacterial strain and resultant intoxication by the bacterial toxin. It also revealed that Curra was pregnant with a 70 days old male fetus that was 6.4 cm long. Tissue samples of the fetus were collected and transported to the Max Delbrück Centre for Molecular Medicine and the Leibniz-IZW in Berlin, Germany. In January 2024, it was confirmed through the analysis of the fetus DNA that the pregnancy resulted from the embryo transfer.

When the BioRescue team arrived in Kenya on November 28, the preliminary results indicated an intoxication with the clostridian bacterial strains Paraclostridium bifermentans and Paenicolostridium sordellii. Immediately after the incident, the BioRescue team, including Kenya Wildlife Service, Wildlife Training Research Institute, Ol Pejeta Conservancy and Safari Park Dvur Králové formed a crisis team on site and established fast and effective measures to protect all current semi-captive rhinos including the last two northern white rhinos Najin and Fatu. The measures included a vaccination programme, quarantine of affected areas and fencing of new emergency enclosures.

The next steps in the BioRescue research programme included the selection and preparation of a new teaser bull. The bull will allow the scientists to know when a possible surrogate female is ready to receive an embryo implantation. The team also has to select the next surrogate mothers. After these steps, which will take several months, an embryo transfer with a northern white rhino embryo will be attempted.

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Sea otters helped prevent widespread California kelp forest declines over the past century

Monterey Bay Aquarium researchers strengthen the link between sea otters and long-term health of California kelp forests in a new study released today. The paper, published in the journal PLOS Climate, finds that sea otter population growth during the last century enhanced kelp forest resilience in the state. This finding reinforces the importance of conservation and recovery of the threatened southern sea otter and highlights a potential nature-based solution for restoring kelp forests along the California coast, and perhaps beyond.

The study revealed dramatic regional kelp canopy changes over a 100-year period, from 1910 to 2016.

During this time there was a significant increase in kelp forest canopy along the central coast, the only region of California where southern sea otters survived after being hunted nearly to extinction for their fur in the 1800s.

At the century scale, the species' favorable impact on kelp forests along the central coast nearly compensated for kelp losses along both northern and southern California resulting in a slight overall decline statewide during this period.

"Our study showed that kelp forests are more extensive and resilient to climate change where sea otters have reoccupied the California coastline during the last century. Where sea otters are absent, kelp forests have declined dramatically. In fact, we found sea otter population density as the strongest predictor of change in kelp canopy coverage across this hundred-year span," said lead author Teri Nicholson, Senior Research Biologist with the Monterey Bay Aquarium Sea Otter Program.

Aquarium scientists used historical surveys of kelp forests dating back to the early 1900s to perform detailed estimates of canopy extent, biomass, and carbon storage -- while correcting for annual variation and differences in survey methods.

This allowed the scientists to examine California's kelp forest trends over a longer time period, going back more than 60 years before available data from modern surveys based on aerial or satellite imagery.

The team then compared the corrected and conservative historical estimates to contemporary datasets and used a machine learning framework to assess the dominant drivers of change over the last century.

"The use of historical maps provided an important opportunity to help us examine long-term kelp forest trends," said Monterey Bay Aquarium Sea Otter Program Manager, Jess Fujii.

"This broader view is important for understanding trends related to climate change, and developing effective science-based conservation strategies."

Statewide, the data showed only a six percent decline in kelp canopy from 1910 to 2016.

Regional changes, however, proved more sizable. Kelp canopy decreased in northern and southern regions by 63 and 52 percent, respectively.

It increased nearly everywhere throughout the central coast, contrastingly, gaining an estimated 56 percent of kelp forest coverage.

While the modeling showed sea otter population density was the strongest predictor of change in kelp coverage, it also identified other factors, including extreme marine heat due to climate change.

"Today, extreme heat in the ocean is intense and persistent. Beginning a decade ago, this threat now affects more than half the ocean's surface," said Kyle Van Houtan, a Research Scientist at Duke University, and senior author of the study.

"This is a major problem for kelp forests as chronic temperature stress undermines kelp growth and health. Ecosystems are complex, and to give them their best chance at surviving these extreme changes, they need all their component parts. Sea otters, of course, are hugely influential for Pacific kelp forests. Historical studies like this are a crucial demonstration of this dynamic over the long term."

Read more at Science Daily

More than a meteorite: New clues about the demise of dinosaurs

What wiped out the dinosaurs? A meteorite plummeting to Earth is only part of the story, a new study suggests. Climate change triggered by massive volcanic eruptions may have ultimately set the stage for the dinosaur extinction, challenging the traditional narrative that a meteorite alone delivered the final blow to the ancient giants.

That's according to a study published in Science Advances, co-authored by Don Baker, a professor in McGill University's Department of Earth and Planetary Sciences.

The research team delved into volcanic eruptions of the Deccan Traps -- a vast and rugged plateau in Western India formed by molten lava.

Erupting a staggering one million cubic kilometres of rock, it may have played a key role in cooling the global climate around 65 million years ago.

The work took researchers around the world, from hammering out rocks in the Deccan Traps to analyzing the samples in England and Sweden.

A new season?: 'Volcanic winters'

In the lab, the scientists estimated how much sulfur and fluorine was injected into the atmosphere by massive volcanic eruptions in the 200,000 years before the dinosaur extinction.

Remarkably, they found the sulfur release could have triggered a global drop in temperature around the world -- a phenomenon known as a volcanic winter.

"Our research demonstrates that climatic conditions were almost certainly unstable, with repeated volcanic winters that could have lasted decades, prior to the extinction of the dinosaurs. This instability would have made life difficult for all plants and animals and set the stage for the dinosaur extinction event. Thus our work helps explain this significant extinction event that led to the rise of mammals and the evolution of our species," said Prof.

Don Baker.

New technique

Uncovering clues within ancient rock samples was no small feat.

In fact, a new technique developed at McGill helped decode the volcanic history.

The technique for estimating sulfur and fluorine releases-a complex combination of chemistry and experiments-is a bit like cooking pasta.

"Imagine making pasta at home. You boil the water, add salt, and then the pasta. Some of the salt from the water goes into the pasta, but not much of it," explains Baker.

Similarly, some elements become trapped in minerals as they cool following a volcanic eruption.

Just as you could calculate salt concentrations in the water that cooked the pasta from analyzing salt in the pasta itself, the new technique allowed scientists to measure sulfur and fluorine in rock samples.

With this information, the scientists could calculate the amount of these gases released during the eruptions.

Read more at Science Daily

Scientists zero in on timing, causes of ice age mammal extinctions in southern California

The end of the last Ice Age also marked the end for more than three dozen genera of large mammals in North America, from mammoths and mastodons to bison and saber-toothed cats. Details concerning the precise timing and circumstances, however, have remained murky ever since.

A team of scientists that included Texas A&M University archaeologist Dr. Michael Waters recently focused on the well-known Rancho La Brea Tar Pits in southern California in their quest to provide answers to these questions, resulting in the most exact and detailed timeline for the extinctions that happened during the latter part of the Pleistocene period in North America, along with some foreboding insight into the area's present and future. Their work is featured on the cover of the current issue of Science.

Waters, a distinguished professor in the Department of Anthropology and director of the Center for the Study of the First Americans (CSFA), along with roughly a dozen fellow researchers, examined the timing and cause of the extinction of a variety of large mammals, known as megafauna, that got stuck in tar at Rancho La Brea, ensuring the preservation of their bones. The team used the radiocarbon dating method to date 169 bones from seven different animals -- bison, horse, camel and ground sloths as well as the carnivores that ate them, including the saber-toothed cat, dire wolf and American lion. They also compared those findings to regional pollen and charcoal records along with continent-wide data on human and large mammal populations.

Armed with their new data, the researchers subsequently used time-series modeling to produce the most detailed chronobiology to date, showing the relationships between climate and vegetation change, fire activity, human demographics and megafauna extinctions -- groundbreaking results they report in the Aug. 18 edition of the world-leading academic journal.

Waters says the team's findings reveal that Ice Age mammal populations in southern California were steady from 15,000 to around 13,250 years ago. Afterward, there was a sharp decline in the population of the seven animals studied, and they all became extinct between 13,070 to 12,900 years ago.

In an interesting modern-day parallel, this extinction event corresponds with a change in the environment from 13,300 to 12,900 years ago marked by warming and drying that made the land more vulnerable to fires in southern California. Charcoal records show that fires increased around 13,500 years ago and peaked between 13,200 and 12,900 years ago. Studies show that humans arrived in North America's Pacific coast 16,000 to 15,000 years ago and lived alongside the megafauna for 2,000 to 3,000 years before their extinction.

While humans hunted animals during this period, Waters says the impact of hunting on the demise of the megafauna likely was minor because of the low population of humans on the landscape. However, the fires would have been devastating, resulting in the loss of habitat causing the rapid decline and extinction of the megafauna in southern California. The study suggests these fires were ignited by humans, which had increased in number by that time.

"Fire is a way that small numbers of humans can have a large impact over a broad area," said Waters, who also cautions that climate changes observed in present-day California are similar to those of the late Pleistocene.

"This study has implications for the changes we see in southern California today," Waters added. "The temperatures are rising, and the area is drying. We also see a dramatic increase in fires. It appears that history may be repeating itself."

While Waters acknowledges that this is the story of extinction at Rancho La Brea, he says it has the potential to offer insights into when extinctions happened across all of North America.

"Mammoths and mastodons survived in many parts of North America until around 12,700 years ago," he added. "These animals were hunted by the Clovis people between about 13,000 and 12,700 years ago. We are now dating megafauna remains from other locations to give a broader understanding of the Rancho La Brea research in the context of North America."

The museum at La Brea Tar Pits holds the world's largest collection of fossils from the Ice Age and has been central to the study of animal and plant life at the end of the Pleistocene epoch for more than a century. Its naturally occurring asphalt pools entrapped and preserved the bones of thousands of individual animals representing dozens of megafaunal species during the last 60,000 years, enabling scientists to determine when different species disappeared from the ecosystem and why.

Read more at Science Daily

Lost giants: New study reveals the abundance decline of African megafauna

Faysal Bibi (Museum für Naturkunde, Berlin) and Juan L. Cantalapiedra (University of Alcalá, Madrid) used measurements of thousands of fossil teeth to reconstruct the size and abundance of African large mammals (>15 kg) over the last 10 million years. Despite many uncertainties affecting preservation in the fossil record, the study revealed a highly similar relationship between an animal's size and its abundance between fossil and extant communities, indicating that fundamental ecological processes governing the structure of living communities are also preserved in the fossil record.

Above 45 kg, the researchers found evidence for decreasing abundance with increasing size, a pattern that aligns with the ecological 'rule of metabolic scaling', whereby larger species have lower population densities compared to smaller ones. A deviation from the predicted ecological pattern was that mammals between ~15 and 45 kg were far less numerous than expected, both in living and fossil communities. They interpreted this as a signature of savanna habitats (where monkeys and small forest-living antelopes are rare).

The big surprise came when the researchers examined how size-abundance distributions changed over time. They discovered that earlier communities, older than ~4 million years ago, had a considerably higher number of large-sized individuals and a greater proportion of total biomass in larger size categories, than did younger communities. The high abundance of large individuals in these fossil African communities -- with some individual elephants reaching sizes over 10 tons -- is unparalleled in ecosystems today. Since that time, there has been a gradual loss of large-sized individuals from the fossil record, reflecting the long-term decline of late Pliocene and Pleistocene large mammal diversity, and resulting in the impoverished and 'miniaturized' communities we know today.

The study confirms recent work arguing for the deep-time antiquity of African megafaunal losses and challenging the idea that the decline of African megafauna was primarily driven by human activities. While the spread of humans across the globe during the late Pleistocene and Holocene (the last ~100,000 years) coincided with major extinction of many large animals, the research supports the idea that megafaunal losses in Africa began much earlier, around 4 million years ago, and long before humans learned to engage in efficient hunting. Instead, the study highlights environmental factors, such as the long-term decrease in global temperatures and the expansion of tropical grasslands, as potential drivers of megafaunal extinctions.

The study also found that the loss of large individuals and the restructuring of biomass distributions in African large mammal communities could have been linked to decreases in primary productivity. Using an established relationship between the types of mammalian tooth shapes (morphological traits) and plant productivity (net primary productivity) today, the researchers calculated productivity for African communities in the past. They found an approximately two-thirds decrease in productivity since the Late Miocene (> 5 million years ago), a pattern observed globally, and that could have significantly diminished the carrying capacity of large mammal communities, leading to reduced diversity and accelerated extinction of large species.

The research opens new avenues for understanding the dynamics of ecosystems and the complex interactions between individuals, species, and their environment. By analyzing fossil abundance data and incorporating size-based approaches, scientists can gain valuable insights into the ecological dynamics underlying extinction.

Read more at Science Daily

Dinosaurs were the first to take the perspectives of others

When someone near you turns their head towards something in the environment, you likely can't help to follow their gaze direction. This reaction is observed in mammals, birds and even reptiles alike. It's an effective way to gather information about what caught the attention of your fellow, which you might otherwise have missed. However, a far more advanced behavior is to follow someone's gaze to a location that is initially obstructed from your view. By repositioning yourself to see what the other person is looking at, you demonstrate an understanding that the other has a different perspective. This ability, known as visual perspective taking develops in children between the ages of one-and-a-half to two years and serves as the foundation for later comprehending referential communication and that others have minds that differ from your own.

Visual perspective taking has, to date, only been found in very few species. Mainly in apes and some monkeys, but also in dogs and crow birds. However, there is limited knowledge regarding the evolutionary origins of this crucial social skill. A team of researchers from Lund University aimed to investigate a potential early emergence of visual perspective taking in dinosaurs. Through a comparison of alligators with the most primitive existing birds, known as palaeognaths, they discovered that visual perspective taking originated in the dinosaur lineage likely 60 million years, or more, prior to its appearance in mammals.

Crocodilians are the closest living relatives to birds. Their neuroanatomy has remained largely unchanged for hundreds of millions of years, and is similar to that of the common ancestor of dinosaurs and crocodilians. Palaeognath birds comprise the ostrich birds, such as emus and rheas, but also the flighted tinamous. Their brains are in large parts comparable to their forebearers, the non- avian paravian dinosaurs, which feature such celebrities as the velociraptors. Comparing these two groups of animals creates a bracket around the extinct lineage of dinosaurs leading up to modern birds.

The study revealed that alligators do not demonstrate visual perspective taking, although they do follow gaze to a visible location. In contrast, all tested bird species exhibited visual perspective taking. Additionally, the birds engaged in a behaviour called "checking back," where the observer looks back into the eyes of the gazer, and re-tracks the gaze, when unable to find anything in the direction of their gaze the first time. This behaviour indicates an expectation that the gaze is referring to a target in the environment. Previously, this has only been observed in humans, apes and monkeys, and ravens.

Palaeognath birds emerged 110 million years ago, predating the two mammal groups endowed with visual perspective taking -- primates and dogs -- with 60 million years. Considering the neuroanatomical similarities between these birds and their non-avian forebearers, it is plausible that the skill originated even earlier in the dinosaur lineage. However, it is less likely to have been present among the earliest dinosaurs, which had more alligator-like brains. Maybe future research will show the ability to be more widespread among mammals than currently known, but even if that would be the case it will most probably still be predated by the dinosaur origin. Nevertheless, it is not surprising that visual perspective taking emerged earlier in the dinosaurs, which include the birds, given their superior vision compared to most mammals, that historically relied on nocturnal adaptations. It was only with the emergence of the primates and certain carnivores that our visual capabilities improved.

This is yet another finding that calls into question the prevailing view that mammals drove the evolution of complex cognition, and that they are the cognitive yardstick to which other animals should be compared. An increasing number of studies show the remarkable neurocognition of the avian dinosaurs, the birds, which might prompt a rethinking of the natural history of cognition.

Comments from the authors:

Senior author, prof. Mathias Osvath: "Early in my career, crow birds earned the nickname "feathered apes," due to numerous research findings that showcased their remarkable cognition. However, I'm beginning to question whether it would be more fitting to consider primates as honorary birds."

First author (then PhD-student), Dr Claudia Zeiträg: "Birds are commonly being overlooked when it comes to their cognitive skills. Our findings show that they do not only have several cognitive skills on par with those of apes, but that their forebearers most likely had these skills long before they evolved in mammals."

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Global warming puts whales in the Southern Ocean on a diet

In the month of June, when winter bites in the southern hemisphere and the sea around the Antarctic freezes over, right whales swim north. Many of them gather in the bay outside the town of Hermanus in South Africa.

Here, the warmer South African water is perfect for mating or raising newborn calves. However, there is no food for the whales, and all winter long the right whale mothers use up their fat reserves to produce milk for their calves.

It is therefore extremely important that the whales eat a lot and fatten up in the cold waters around the Antarctic throughout the summer. But it seems there is not enough food. The whales arriving at the coasts of South Africa are thinner than they used to be.

This is the result of new research from Aarhus University. Since the researchers started to measure right whales in the 1980s, the whales have become increasingly thinner. This is explained by Fredrik Christiansen, a senior researcher at the Department of Ecoscience at Aarhus University, who is behind the new results.

"Right whales are 25 per cent thinner than they were in the 1980s. This is bad for the whale population, because it means that the newborn whale calves have a higher risk of dying. Fortunately, the right whales in the Southern Ocean are not endangered, but if this continues, they could become so," he says.

When the ice melts, food disappears

When winter comes, and the cows leave the Antarctic and swim north, they have to cope for several months without food. Several months in which they eat into the fat reserves they have built up through the warm and light summer season.

Throughout the summer, right whales swim around beneath the sea ice, open their mouths to take in seawater, krill and water fleas. The baleen inside their mouth is a sort of a giant filter and it filters the small animals from the salt water. This allows the whales to eat huge amounts of food without using a lot of energy.

But the large shoals of krill are shrinking -- and this means that the whales can't fatten up before winter as they used to," explains Fredrik Christiansen.

"The shoals of krill live on phytoplankton, which thrive best in the cold waters around the Antarctic. Here -- like plants on land -- they transform sunlight into energy. Rising sea temperatures mean there is less phytoplankton, fewer krill and thus less food for the whales.

Instead, the whales forage for food further north, where there is another and less energy-rich form of krill.

"Further north, there's less food for these small crustaceans. Therefore, they're not as big and fat as the animals living beneath the Antarctic sea ice," he says.

How to weigh a whale

How exactly do scientists know that the whales have become thinner? Do Fredrik Christiansen and his colleagues lift the huge animals out of the water with oversized weighing scales? No, he explains. Instead, the researchers have invented a method to work out the weight of the whales based on photographs taken by drones.

"Right whales like to lie flat on the sea surface. This makes them easy to photograph from above. When the drone has taken some photographs -- and we know the height of the drone -- we can calculate the size of the animal," he explains.

However, in order to know the weight of the whale, it is necessary to know the volume of the whale -- not just the length and width. But because scientists like Fredrik Christiansen have observed many right whales rolling around on the sea surface over the years -- and thereby have been able to measure their size -- the scientists now know the relationship between length, width and volume of the whales.

"We calculate the volume using the drone photographs -- and when we know the volume, we more or less know the weight. In this way, we can see that the whales have become thinner over the past 30 years -- and that's serious. The weight of the mothers has a huge impact on their calves," he says.

Small and weak whale calves

Thirty to forty years ago, the southern right whale had calves every three years on average. But this is no longer true, explains Fredrik Oscar Christiansen.

"In the 1980s, researchers observed that the right whales off the coast of South Africa gave birth to a new calf every three years. But because it's now difficult for them to fatten up during summer, this has fallen to every five years. This means that the population is growing significantly more slowly.

And not only do the whale calves come more rarely. The calves born today are smaller and grow more slowly.

"The amount of fat on the whale mother is directly linked to how much energy she can give to her calf through her milk. When the mother is thin, the calf gets less energy and grows more slowly," he says.

The researchers have discovered that the northern right whales in the waters off Canada and the northern US are not growing quite as big as before. This is possibly because the calves are born smaller. According to the researchers' calculations, a whale born in 2019 will be one metre shorter on average when it is fully grown than a whale born in 1981.

"Small calves have a higher risk of dying. They're more vulnerable if a killer whale attacks."

Hunted close to extinction

Right whales were given their name because they were considered the "right" whales to catch. People began hunting the large whales as early as in the 14th century, and for hundreds of years, they were hunted fiercely in both northern and southern parts of the Atlantic.

Oil from the whales' fat was one of the most important sources of energy. Train oil, which the oil used to be called, became a fuel in lamps -- both for indoors and for street lights. The demand for train oil was also one of the most important reasons why Denmark colonised Greenland in the 18th century.

Around 1900, train oil was replaced by another more efficient energy source: crude oil. The black gold pumped up from the underground meant that whale hunting was no longer profitable.

The southern right whale is one of the species that benefitted from the end of whaling. For more than 100 years, the population has been allowed to grow large and healthy again. And this is not just good for the whales, but also for the entire Southern Ocean ecosystem.

Because the whales bring nourishment to areas of the sea with little food.

Extremely important for the marine ecosystem

The sea around the Antarctic where the right whales come to eat has more life than any other sea on the planet. Despite the fact that the area only contains five per cent of the Earth's sea water, 20 per cent of all marine life lives in the area.

The many hours of sunshine in the summer, turbulent sea currents and the low temperature are perfect for teeming life.

The light makes marine algae grow explosively. The sea currents swirl the algae and nourishment around so that krill and plankton can gorge themselves. When full, the small crustaceans reproduce and form gigantic swarms. In some places, there may be as many as 35,000 krill in one cubic metre of water.

The right whales -- and many other animals -- stuff themselves with the abundance of krill, but unlike many other species, the whales migrate thousands of kilometres north to overwinter.

"The whales are extremely important for the parts of the sea where there is not much food. When the whales die, their huge bodies sink to the bottom. In the depths, they become food for a whole ecosystem of eel, sharks, crabs, lobsters, worms and microorganisms," says Fredrik Christiansen.

Read more at Science Daily

Scientists show how we can anticipate rather than react to extinction in mammals

Most conservation efforts are reactive. Typically, a species must reach threatened status before action is taken to prevent extinction, such as establishing protected areas. A new study published in the journal Current Biology on April 10 shows that we can use existing conservation data to predict which currently unthreatened species could become threatened and take proactive action to prevent their decline before it is too late.

"Conservation funding is really limited," says lead author Marcel Cardillo of Australian National University. "Ideally, what we need is some way of anticipating species that may not be threatened at the moment but have a high chance of becoming threatened in the future. Prevention is better than cure."

To predict "over-the-horizon" extinction risk, Cardillo and colleagues looked at three aspects of global change -- climate change, human population growth, and the rate of change in land use -- together with intrinsic biological features that could make some species more vulnerable. The team predicts that up to 20% of land mammals will have a combination of two or more of these risk factors by the year 2100.

"Globally, the percentage of terrestrial mammal species that our models predict will have at least one of the four future risk factors by 2100 ranges from 40% under a middle-of-the-road emissions scenario with broad species dispersal to 58% under a fossil-fueled development scenario with no dispersal," say the authors.

"There's a congruence of multiple future risk factors in Sub-Saharan African and southeastern Australia: climate change (which is expected to be particularly severe in Africa), human population growth, and changes in land use," says Cardillo. "And there are a lot of large mammal species that are likely to be more sensitive to these things. It's pretty much the perfect storm."

Larger mammals in particular, like elephants, rhinos, giraffes, and kangaroos, are often more susceptible to population decline since their reproductive patterns influence how quickly their populations can bounce back from disturbances. Compared to smaller mammals, such as rodents, which reproduce quickly and in larger numbers, bigger mammals, such as elephants, have long gestational periods and produce fewer offspring at a time.

"Traditionally, conservation has relied heavily on declaring protected areas," says Cardillo. "The basic idea is that you remove or mitigate what is causing the species to become threatened."

"But increasingly, it's being recognized that that's very much a Western view of conservation because it dictates separating people from nature," says Cardillo. "It's a sort of view of nature where humans don't play a role, and that's something that doesn't sit well with a lot of cultures in many parts of the world."

In preventing animal extinction, the researchers say we must also be aware of how conservation impacts Indigenous communities. Sub-Saharan Africa is home to many Indigenous populations, and Western ideas of conservation, although well-intended, may have negative impacts.

Australia has already begun tackling this issue by establishing Indigenous Protected Areas (IPAs), which are owned by Indigenous peoples and operate with the help of rangers from local communities. In these regions, humans and animals can coexist, as established through collaboration between governments and private landowners outside of these protected areas.

Read more at Science Daily

Thousands of native plants are unphotographed, and citizen scientists can help fill the gaps

Scientists have documented plant species for centuries to help us understand and protect the incredible diversity of flora in our world. But according to new research, many have never actually been photographed in their natural habitats -- and that's a problem.

Researchers from UNSW Sydney and the Australian Institute of Botanical Science, part of the Royal Botanic Gardens and Domain Trust, surveyed 33 major online databases of plant photographs to examine the photographic record of Australian plant species. The findings, published in New Phytologist, reveal out of 21,077 native Australian vascular plant species, almost 20 per cent lack a verifiable photograph.

Lead author of the study and UNSW Science PhD student Thomas Mesaglio says Australia is one of the richest areas in the world for native species.

"It was surprising to see how many plant species had just line drawings, illustrations, paintings, or even no media at all," Mr Mesaglio says.

Dr Hervé Sauquet, co-author of the study and Senior Research Scientist at the Australian Institute of Botanical Science, is based at the National Herbarium of New South Wales.

"All species of plants ultimately rely on specimens in herbarium collections for their identification," Dr Sauquet says. "Yet, even in this digital age where most herbarium specimens have been scanned and are accessible on the web, photos of live plants in the wild remain in critical need."

Senior author of the study from UNSW Science Associate Professor Will Cornwell says a lack of detailed photos can have real consequences. Many plant species that are difficult to identify in the wild may go extinct if scientists cannot properly identify them with the help of photos.

"We had assumed every plant species would have simply been photographed by someone, somewhere, throughout history. But it turns out this isn't the case," says A/Prof. Cornwell.

"This is where citizen scientists can come in and help us fill this gap with their photos."

Gaps in the photographic record

Photographs can help botanists and taxonomists who work with plant specimens by preserving characteristics like flower colour that get lost over time in their samples. They can also show additional features, such as the orientation of leaves or bark appearance, and add ecological context.

"Having a comprehensive photographic set helps us to be confident in our identifications," Mr Mesaglio says. "Particularly when it is practically challenging to collect and preserve the entire plant, photos complement the physical voucher by showing the soil type, the habitat it's growing in, and other species growing alongside it."

But it turns out not all plant groups are photographed equally. Just as some animals receive less attention than others, there might also be a bias against less charismatic plants.

The study found the most well-photographed plant groups tend to be shrubs or trees with more noticeable or spectacular features, such as colourful flowers. Banksia, for example, is one of only two Australian plant genera with more than 40 species to have a complete photographic record. Meanwhile, the family with the most significant photo deficit was Poaceae -- commonly known as grasses -- with 343 unphotographed species.

"We noticed a charisma deficit, so the species that tend to be harder to see are the ones missing out," Mr Mesaglio says. "They may have innocuous or pale-looking flowers or be smaller and harder to spot grasses, sedges and herbs."

Geography also affected the photographic record. While most species across the south-eastern states of Australia have comprehensive records, Western Australia had the largest void, with 52 per cent of all unphotographed species found there.

"The primary 'hotspots' for unphotographed Australian plants are areas with high plant diversity, but the environments are rugged and often difficult to access, particularly by road," Mr Mesaglio says. "But it means there's an exciting opportunity to visit these locations because we might capture something that has never before been photographed."

Activating citizen scientist snaps

It's one thing to have comprehensive photographic records for professional scientists to use in identification guides. But when the plant world is under threat from multiple fronts, including habitat clearing and climate change, photos can help engage the public in plant science.

"People can engage with, sympathise with, and get much more excited about plants with photographs, which is vital when our natural environments are more at risk than ever," Mr Mesaglio says.

"Because digital photography is so accessible now, anyone can also help make a meaningful contribution to science using the camera in their pocket."

Using a platform like iNaturalist, keen citizen scientists can have their snaps identified by experts and share the data with aggregators like the Atlas of Living Australia and the Global Biodiversity Information Facility to be used in research and conservation.

"Since April last year, we've identified nearly 10 per cent of those previously unphotographed species thanks to members of the public uploading their photographs and experts who've kindly identified them," Mr Mesaglio says. "There could be many more in personal collections or behind paywalls just waiting to be shared."

The researchers recommend a standardised system for scientific plant photography be developed, starting with a requirement in the International Code of Nomenclature for Plants to include at least one field photograph where possible in new species descriptions. They also suggest all new species descriptions be published as Open Access in searchable databases with Creative Commons licensing to maximise their usage.

"We also suspect more photos exist, but they're hidden away on social media or behind scientific paywalls that aren't accessible, discoverable, or searchable," Mr Mesaglio says.

Read more at Science Daily

Climate change played key role in dinosaur success story

Climate change, rather than competition, played a key role in the ascendancy of dinosaurs through the Late Triassic and Early Jurassic periods.

According to new research, changes in global climate associated with the Triassic-Jurassic mass extinction -- which wiped out many large terrestrial vertebrates such as the giant armadillo-like aetosaurs -- actually benefitted the earliest dinosaurs.

In particular, sauropod-like dinosaurs, which became the giant herbivore species of the later Jurassic like Diplodocus and Brachiosaurus, were able to thrive and expand across new territories as the planet warmed up after the extinction event, 201 million years ago.

The new evidence is published in Current Biology, by an international team of palaeontologists led by the Universities of Birmingham and Bristol, in the UK, Friedrich-Alexander University Erlangen-Nu?rnberg (FAU), in Germany, and the University of São Paulo in Brazil.

The team compared computer models of prehistoric global climate conditions such as temperature and rainfall with data on the different locations of dinosaurs taken from sources such as the Paleobiology Database. They showed how the sauropods, and sauropod-like animals, with their long tails and necks and small heads, were the runaway success story of a turbulent period of evolution.

Dr Emma Dunne, now a lecturer in palaeontology at FAU, carried out the research while at the University of Birmingham. She said: "What we see in the data suggests that instead of dinosaurs being outcompeted by other large vertebrates, it was variations in climate conditions that were restricting their diversity. But once these conditions changed across the Triassic-Jurassic boundary, they were able to flourish.

"The results were somewhat surprising, because it turns out that sauropods were really fussy from the get-go: later in their evolution they continue to stay in warmer areas and avoid polar regions."

Co-author on the paper, Professor Richard Butler, at the University of Birmingham, said: "Climate change appears to have been really important in driving the evolution of early dinosaurs. What we want to do next is use the same techniques to understand the role of climate in the next 120 million years of the dinosaur story."

Read more at Science Daily

Mammoth problem with extinction timeline

Precisely when mammoths went extinct has fascinated paleontologists for generations, perhaps because their decline coincided with the arrival of people to North and South America.

So it's only natural to wonder if humans contributed to the extinction of these enormous beasts of the ice age more than 10,000 years ago.

A University of Cincinnati paleontologist refutes the latest timeline published in 2021 in the journal Nature that suggested mammoths met their end much more recently than we believed. An international team of researchers examined environmental DNA of mammoth remains and more than 1,500 arctic plants to conclude that a wetter climate quickly changed the landscape from tundra grassland steppe to forested wetlands that could not support many of these big grazing animals, driving mammoths to extinction as recently as 3,900 years ago.

But in a rebuttal paper in Nature, UC College of Arts and Sciences assistant professor Joshua Miller and co-author Carl Simpson at the University of Colorado Boulder argue that the environmental DNA used to establish their updated timeline is more complex than previously recognized.

"The issue is you have no idea how old that DNA is," Miller said. "Sedimentary deposits are complex. Materials of different ages are routinely buried together."

Researchers have many tools to date sedimentary deposits and the materials contained in them. But not everything can be dated, Miller said.

"We can radiocarbon date all kinds of things: bones, teeth, charcoal, leaves. That's very powerful. But currently we can't independently date DNA found in sediments," Miller said.

From recent discoveries like the baby mammoth found in Canada this year, we know that many ice age animals that died tens of thousands of years ago can become mummified in the arctic's dry, cold environment. Miller said researchers can't tell whether environmental DNA preserved in sediment was shed from a living or dead animal.

"DNA is shed from organisms all the time," Miller said. "In fact, DNA continues to be shed long after the animal dies. In places where decomposition is slow, that means long-dead and even long-extinct species can continue to make their way into surrounding sediments. In the arctic and other cold-weather places, it can take thousands of years for something to decompose."

The researchers say the slow decomposition of animals in arctic regions could explain how mammoth DNA is showing up thousands of years later than the most recent mammoth fossil discovered. The paper notes that the mummified remains of elephant seals near Antarctica can be more than 5,000 years old.

Simpson said his work studying marine environments from recently eroded hillsides demonstrates how difficult it is to date ancient specimens.

"Seashells can sit on the seafloor for thousands of years. When you see shells on the beach, some could be from animals that died recently while others might be from shellfish that died millennia ago," Simpson said. "This happens in the vertebrate record as well."

Miller said the question remains what impact, if any, humans had on the global decline and extinction of mammoths. Humans were known to use fire to alter landscapes in profound ways, Miller said. They also hunted mammoths and made use of their ivory tusks.

So when did the last mammoths die off? Scientists say most mammoths went extinct more than 10,000 years ago, but remnant populations lived on islands such as Russia's Wrangel Island until much more recently.

This cohabitation with modern humans is one reason mammoths capture our imaginations, researchers said.

"They're tantalizingly similar to animals that live among us today," Miller said. "We can almost touch them. That makes mammoths really alluring. For many people they are the poster children of ice age megafauna."

Simpson noted that mammoths once lived on the Channel Islands of California near where he grew up. The islands were home to a pygmy mammoth weighing 2,000 pounds. Today, the biggest mammal on the island is a tiny endemic fox.

Read more at Science Daily

Planet's rarest birds at higher risk of extinction

A new study finds that bird species with extreme or uncommon combinations of traits face the highest risk of extinction. The findings are published in the British Ecological Society journal Functional Ecology.

A new study led by researchers at Imperial College London finds that the most unique birds on the planet are also the most threatened. Losing these species and the unique roles they play in the environment, such as seed dispersal, pollination and predation, could have severe consequences to the functioning of ecosystems.

The study analysed the extinction risk and physical attributes (such as beak shape and wing length) of 99% of all living bird species, making it the most comprehensive study of its kind to date.

The researchers found that in simulated scenarios in which all threatened and near-threatened bird species became extinct, there would be a significantly greater reduction in the physical (or morphological) diversity among birds than in scenarios where extinctions were random.

Bird species that are both morphologically unique and threatened include the Christmas Frigatebird (Fregata andrewsi), which nests only on Christmas Island, and the Bristle-thighed Curlew (Numenius tahitiensis), which migrates from its breeding grounds in Alaska to South Pacific islands every year.

Jarome Ali, a PhD candidate at Princeton University who completed the research at Imperial College London and was the lead author of the research, said: "Our study shows that extinctions will most likely prune a large proportion of unique species from the avian tree. Losing these unique species will mean a loss of the specialised roles that they play in ecosystems.

"If we do not take action to protect threatened species and avert extinctions, the functioning of ecosystems will be dramatically disrupted."

In the study, the authors used a dataset of measurements collected from living birds and museum specimens, totalling 9943 bird species. The measurements included physical traits like beak size and shape, and the length of wings, tails and legs.

The authors combined the morphological data with extinction risk, based on each species' current threat status on the IUCN Red List. They then ran simulations on what would happen if the most threatened birds were to go extinct.

Although the dataset used in the study was able to show that the most unique birds were also classified as threatened on the Red List, it was unable to show what links uniqueness in birds to extinction risk.

Read more at Science Daily

Entomologists issue warning about effects of climate change on insects

In a new scientific review, a team of 70 scientists from 19 countries warned that if no steps are taken to shield insects from the consequences of climate change, it will "drastically reduce our ability to build a sustainable future based on healthy, functional ecosystems."

Citing research from around the world, the team painted a bleak picture of the short- and long-term effects of climate change on insects, many of which have been in a state of decline for decades. Global warming and extreme weather events are already threatening some insects with extinction -- and it will only get worse if current trends continue, scientists say. Some insects will be forced to move to cooler climes to survive, while others will face impacts to their fertility, life cycle and interactions with other species.

Such drastic disruptions to ecosystems could ultimately come back to bite people, explained Anahí Espíndola, an assistant professor of entomology at the University of Maryland and one of the paper's co-authors.

"We need to realize, as humans, that we are one species out of millions of species, and there's no reason for us to assume that we're never going to go extinct," Espíndola said. "These changes to insects can affect our species in pretty drastic ways."

Insects play a central role in ecosystems by recycling nutrients and nourishing other organisms further up the food chain, including humans. In addition, much of the world's food supply depends on pollinators like bees and butterflies, and healthy ecosystems help keep the number of pests and disease-carrying insects in check.

These are just a few of the ecosystem services that could be compromised by climate change, the team of scientists cautioned. Unlike mammals, many insects are ectotherms, which means they are unable to regulate their own body temperature. Because they are so dependent on external conditions, they may respond to climate change more acutely than other animals.

One way that insects cope with climate change is by shifting their range, or permanently relocating to places with lower temperatures. According to one study cited by Espíndola and other scientists, the ranges of nearly half of all insect species will diminish by 50% or more if the planet heats up 3.2°C. If warming is limited to 1.5°C -- the goal of the global Paris Agreement on climate change -- the ranges of 6% of insects will be affected.

Espíndola, who studies the ways in which species respond to environmental changes over time, contributed to the sections of the paper that address range shifts. She explained that drastic changes to a species' range can jeopardize their genetic diversity, potentially hampering their ability to adapt and survive.

On the other hand, climate change may make some insects more pervasive -- to the detriment of human health and agriculture. Global warming is expected to expand the geographical range of some disease vectors (such as mosquitoes) and crop-eating pests.

"Many pests are actually pretty generalist, so that means they are able to feed on many different types of plants," Espíndola said. "And those are the insects that -- based on the data -- seem to be the least negatively affected by climate change."

The team noted that the effects of climate change are often compounded by other human-caused impacts, such as habitat loss, pollution and the introduction of invasive species. Combined, these stressors make it more difficult for insects to adapt to changes in their environment.

Though these effects are already being felt by insects, it is not too late to take action. The paper outlined steps that policymakers and the public can take to protect insects and their habitats. Scientists recommended "transformative action" in six areas: phasing out fossil fuels, curbing air pollutants, restoring and permanently protecting ecosystems, promoting mostly plant-based diets, moving towards a circular economy and stabilizing the global human population.

The paper's lead author, Jeffrey Harvey of the Netherlands Institute of Ecology (NIOO-KNAW) and Vrije Universiteit Amsterdam, said in a statement that urgent action is needed to protect insects and the ecosystems they support.

"Insects are tough little critters, and we should be relieved that there is still room to correct our mistakes," Harvey said. "We really need to enact policies to stabilize the global climate. In the meantime, at both government and individual levels, we can all pitch in and make urban and rural landscapes more insect-friendly."

The paper suggested ways that individuals can help, including managing public, private or urban gardens and other green spaces in a more ecologically-friendly way -- for instance, incorporating native plants into the mix and avoiding pesticides and significant changes in land usage when possible.

Read more at Science Daily

Impact that killed the dinosaurs triggered 'mega-earthquake' that lasted weeks to months

66 million years ago, a 10-kilometer asteroid hit Earth, triggering the extinction of the dinosaurs. New evidence suggests that the Chicxulub impact also triggered an earthquake so massive that it shook the planet for weeks to months after the collision. The amount of energy released in this "mega-earthquake" is estimated at 1023 joules, which is about 50,000 times more energy than was released in the magnitude 9.1 Sumatra earthquake in 2004.

Hermann Bermúdez will present evidence of this "mega-earthquake" at the upcoming GSA Connects meeting in Denver this Sunday, 9 October. Earlier this year, with support from a GSA Graduate Student Research Grant, Bermúdez visited outcrops of the infamous Cretaceous-Paleogene (K-Pg) mass extinction event boundary in Texas, Alabama, and Mississippi to collect data, supplementing his previous work in Colombia and Mexico documenting evidence of the catastrophic impact.

In 2014, while doing fieldwork on Colombia's Gorgonilla Island, Bermúdez found spherule deposits -- layers of sediment filled with small glass beads (as large as 1.1 mm) and shards known as 'tektites' and 'microtektites' that were ejected into the atmosphere during an asteroid impact. These glass beads formed when the heat and pressure of the impact melted and scattered the crust of the Earth, ejecting small, melted blobs up into the atmosphere, to then fall back to the surface as glass under the influence of gravity.

The rocks exposed on the coast of Gorgonilla Island tell a story from the bottom of the ocean -- roughly 2 km down. There, about 3,000-km southwest from the site of the impact, sand, mud, and small ocean creatures were accumulating on the ocean floor when the asteroid hit. Layers of mud and sandstone as far as 10-15 meters below the sea floor experienced soft-sediment deformation that is preserved in the outcrops today, which Bermúdez attributes to the shaking from the impact. Faults and deformation due to shaking continue up through the spherule-rich layer that was deposited post-impact, indicating that the shaking must have continued for the weeks and months it took for these finer-grained deposits to reach the ocean floor. Just above those spherule deposits, preserved fern spores signal the first recovery of plant-life after the impact.

Bermúdez explains, "The section I discovered on Gorgonilla Island is a fantastic place to study the K-Pg boundary, because it is one of the best-preserved and it was located deep in the ocean, so it was not affected by tsunamis."

Evidence of deformation from the mega-earthquake is also preserved in Mexico and the United States. At the El Papalote exposure in Mexico, Bermúdez observed evidence of liquefaction -- when strong shaking causes water-saturated sediments to flow like a liquid. In Mississippi, Alabama, and Texas, Bermúdez documented faults and cracks likely associated with the mega-quake. He also documents tsunami deposits at several outcrops, left by an enormous wave that was part of the cascading catastrophes resulting from the asteroid collision.

Bermúdez will deliver a talk about evidence for the mega-earthquake at the GSA Connects meeting in Denver on Sunday, 9 October. He will also present a poster about his observations of tsunami deposits and earthquake-related deformation on Monday, 10 October, which will be available in English, Spanish, Italian, French, and Chinese. In discussing his research, he emphasized the important role collaboration has played in visiting and studying so many outcrops that tell the story of this extreme event in Earth's history.

Read more at Science Daily

Surprising discovery shows a slowing of continental plate movement controlled the timing of Earth's largest volcanic events

Scientists have shed new light on the timing and likely cause of major volcanic events that occurred millions of years ago and caused such climatic and biological upheaval that they drove some of the most devastating extinction events in Earth's history.

Surprisingly the new research, published today in the journal Science Advances, suggests a slowing of continental plate movement was the critical event that enabled magma to rise to the Earth's surface and deliver the devastating knock-on impacts.

Earth's history has been marked by major volcanic events, called Large Igneous Provinces (LIPs) -- the largest of which have caused major increases in atmospheric carbon emissions that warmed Earth's climate, drove unprecedented changes to ecosystems, and resulted in mass extinctions on land and in the oceans.

Using chemical data from ancient mudstone deposits obtained from a 1.5 km-deep borehole in Wales, an international team led by scientists from Trinity College Dublin's School of Natural Sciences was able to link two key events from around 183 million years ago (the Toarcian period).

The team discovered that this time period, which was characterised by some of the most severe climatic and environmental changes ever, directly coincided with the occurrence of major volcanic activity and associated greenhouse gas release on the southern hemisphere, in what is nowadays known as southern Africa, Antarctica and Australia.

On further investigation -- and more importantly -- the team's plate reconstruction models helped them discover the key fundamental geological process that seemed to control the timing and onset of this volcanic event and others of great magnitude.

Micha Ruhl, Assistant Professor in Trinity's School of Natural Sciences, led the team. He said:

"Scientists have long thought that the onset of upwelling of molten volcanic rock, or magma, from deep in Earth's interior, as mantle plumes, was the instigator of such volcanic activity but the new evidence shows that the normal rate of continental plate movement of several centimetres per year effectively prevents magma from penetrating Earth's continental crust.

"It seems it is only when the speed of continental plate movement slows down to near zero that magmas from mantle plumes can effectively make their way to the surface, causing major large igneous province volcanic eruptions and their associated climatic perturbations and mass extinctions.

"Crucially, further assessment shows that a reduction in continental plate movement likely controlled the onset and duration of many of the major volcanic events throughout Earth's history, making it a fundamental process in controlling the evolution of climate and life at Earth's surface throughout the history of this planet."

The study of past global change events, such as in the Toarcian, allows scientists to disentangle the different processes that control the causes and consequences of global carbon cycle change and constrain fundamental Earth system processes that control tipping points in Earth's climate system.

Read more at Science Daily

Only 10 vaquita porpoises survive, but species may not be doomed, scientists say

The vaquita porpoise, the world's smallest marine mammal, is on the brink of extinction, with 10 or fewer still living in Mexico's Gulf of California, their sole habitat. But a genetic analysis by a team of UCLA biologists and colleagues has found that the critically endangered species remains relatively healthy and can potentially survive -- if illegal "gillnet" fishing ceases promptly.

"Interestingly, we found the vaquita is not doomed by genetic factors, like harmful mutations, that tend to affect many other species whose gene pool has diminished to a similar point," said Christopher Kyriazis, a UCLA doctoral student in ecology and evolutionary biology and a co-lead author of the research. "Outlawed fishing remains their biggest threat."

The small porpoises, which range from 4 to 5 feet in length, often become entangled and die in the large mesh gillnets used by poachers hunting the totoaba, an endangered fish highly valued in some countries for its perceived medicinal properties. While Mexico has outlawed totoaba fishing and made the use of these nets in the vaquitas' habitat illegal, many say the bans are not always enforced.

The researchers analyzed the genomes of 20 vaquitas that lived between 1985 and 2017 and conducted computational simulations to predict the species' extinction risk over the next 50 years. They concluded that if gillnet fishing ends immediately, the vaquita has a very high chance of recovery, even with inbreeding. If, however, the practice continues, even moderately, the prospects of recovery are less optimistic.

The research is published May 6 in the journal Science.

"Relative to other species, the vaquita has a higher chance of rebounding from an extreme population crash without suffering severe genetic consequences from inbreeding," said co-lead author Jacqueline Robinson, a postdoctoral scholar at UC San Francisco who earned her doctorate in biology at UCLA. "Genetic diversity in vaquitas is not so low that it constitutes a threat to their health and persistence. It simply reflects their natural rarity."

Genetic diversity is a measure of the differences that exist across the genome among individuals in a population. Large populations tend to have many differences, while naturally smaller or decimated ones have fewer, resulting in individuals that are more genetically similar. That similarity can often result in a greater incidence of harmful mutations that endanger the population since individuals are more likely to inherit the same muted gene from both parents, said senior author Kirk Lohmueller, UCLA associate professor of ecology and evolutionary biology and of human genetics.

"A prevailing view in conservation biology and population genetics is that small populations can accumulate deleterious mutations," Lohmueller said. "However, our finding that the vaquita likely has fewer strongly deleterious mutations hiding in the population means that they are better poised to survive future inbreeding, which bodes well for their overall recovery."

So what protects the vaquitas from the genetic perils of inbreeding? Much of it has to do with the fact that they have always been a small population in a very small habitat in the northern tip of the gulf, the researchers said. While their historic numbers are unknown, the first comprehensive survey in 1997 counted roughly 570 porpoises -- a number that has declined steadily over the last 25 years but which was not large to begin with.

"They're essentially the marine equivalent of an island species," said Robinson, who noted that the species has survived for tens of thousands of years with low genetic diversity. "The vaquitas' naturally low abundance has allowed them to gradually purge highly deleterious recessive gene variants that might negatively affect their health under inbreeding."

In fact, Robinson said, of the 12 marine mammal species -- including vaquitas -- the researchers genetically analyzed, vaquitas had the lowest number of potentially harmful mutations.

While the interplay among small population size, inbreeding and harmful genetic variations is complex, the approach used by the team in this study can help shed light on these dynamics.

"With genomic datasets, we now have the ability to address this complexity," Robinson said. "Species can vary in their levels of harmful genetic variation, and they will not all be affected exactly the same way by reduced population size or inbreeding. There are now many examples of species recovering from extreme declines."

"We hope our analysis is useful not only in demonstrating the potential for the vaquita to recover," Kyriazis said, "but also in highlighting a novel genomics-based simulation approach for endangered species."

Encouragingly, the surviving vaquitas in the northern Gulf of California are actively reproducing and appear healthy. But poachers' gillnets continue to pose an existential threat to the species, and unless further measures are taken to protect the porpoises, there is a distinct possibility they may go extinct. The loss would be a great tragedy, said the study's senior author, UCLA's Robert Wayne.

"The vaquita is symbolic of the unique diversity found in the Gulf of California, which was described by John Steinbeck in his wonderful 1951 book 'The Log From the Sea of Cortez,'" said Wayne, a distinguished professor of ecology and evolutionary biology and a Howard Hughes Medical institute professor. "It represents a unique evolutionary lineage -- there is no similar species anywhere in the world -- and its loss would rob the ecosystem of an important predator adapted to this unique ecosystem."

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Research reveals human-driven changes to distinctive foraging patterns in North Pacific Ocean

The first large-scale study of its kind has uncovered more than 4,000 years' worth of distinctive foraging behaviour in a species once driven to the brink of extinction.

An international team of researchers, led by the University of Leicester, identified long-term patterns in the behaviour of the short-tailed albatross (Phoebastria albatrus) in the North Pacific Ocean by studying isotopes found in archaeological and museum-archived samples of the bird, dating as far back as 2300 BCE.

Their findings, published today (Thursday) in Communications Biology, show long-term patterns in foraging behaviour for the short-tailed albatross for the first time -- and demonstrate how individual birds foraged the same hyper-localised sites for thousands of years in spite of the species' huge potential foraging range across thousands of miles of Pacific coastline and open ocean.

But this behaviour, a demonstration of long-term individual foraging site fidelity (LT-IFSF), can pose significant risks for animals who specialise in areas which may be impacted by human activity.

The short-tailed albatross was brought to the brink of extinction by feather hunters between the 1880s and 1930s and though careful conservation has resulted in exponential population growth in recent decades, this trend of LT-IFSF has not been observed in the last century.

Dr Eric Guiry is Lecturer in Biomolecular Archaeology at the University of Leicester and corresponding author for the study, which focused on two locations close to Yuquot, Canada, and compared findings to sites in the USA, Russia and Japan. He said:

"Understanding migratory behaviour is critical for global biodiversity restoration because it helps identify vulnerable regions for environmental protection.

"Although evidence for the extent and depth of LT-IFSF across other species is still emerging, the extreme distances and time scale of the behaviour seen here indicates that this foraging strategy may be a fundamental, density-driven adaptation that could become widespread again as recovering animal populations reach pre-industrial levels."

The research team from Leicester, the Land of Maquinna Cultural Society (Canada), Vrije Universiteit Brussel (Belgium) and Simon Fraser University (Canada) were able to track this foraging behaviour by examining stable carbon and nitrogen isotope compositions in samples of bone collagen.

In contrast to most other tissues such as muscle or feather, which turn over on a scale of days, weeks, or months), isotopic compositions from bone collagen, which remodels slowly over the entire lifespan on an individual, reflect an average of foods consumed over the last several years of an individual's life.

This provides a unique perspective for exploring lifetime trends in animal diet and migration behaviour.

By mapping these biological markers against known isotopic baselines across the species' foraging range, linked to factors such as sea surface temperature and CO2 concentrations, the researchers were able to build up a picture of the short-tailed albatross' migratory and foraging behaviour over hundreds of generations.

But, crucially, as this behaviour is no longer observed among these birds, their findings show this hyper-specialised foraging in specific locations disappeared after the birds were hunted to near extinction in the 1880s, when only a handful of birds remained. Dr Guiry continued:

"We think this behaviour could be driven by competition among birds, meaning that, as the population recovers, we could see it re-emerge. This kind information is important because it provides advanced warning that monitoring for this remarkable behaviour, which can make the birds more vulnerable to human impacts, may need close attention.

"One of the most exciting findings, however, is actually quite a positive note. Our data also indicate that Indigenous communities at Yuquot were harvesting these birds with little impact on their population for thousands of years.

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