Dinosaur tongues, new research


This 2017 video is called How to Sculpt a Dinosaur Part 2 – Eyes, Teeth, Tongue & Skin Texture – PREVIEW.

From the University of Texas at Austin in the USA:

T. Rex couldn’t stick out its tongue

June 20, 2018

Dinosaurs are often depicted as fierce creatures, baring their teeth, with tongues wildly stretching from their mouths like giant, deranged lizards. But new research reveals a major problem with this classic image: Dinosaurs couldn’t stick out their tongues like lizards. Instead, their tongues were probably rooted to the bottoms of their mouths in a manner akin to alligators.

Researchers from The University of Texas at Austin and the Chinese Academy of Sciences made the discovery by comparing the hyoid bones — the bones that support and ground the tongue — of modern birds and crocodiles with those of their extinct dinosaur relatives. In addition to challenging depictions of dino tongues, the research proposes a connection on the origin of flight and an increase in tongue diversity and mobility.

The research was published June 20 in the journal PLOS ONE.

“Tongues are often overlooked. But, they offer key insights into the lifestyles of extinct animals,” said lead author Zhiheng Li, an associate professor at the Key Laboratory of Vertebrate Evolution and Human Origins of the Chinese Academy of Sciences.He conducted the work while earning his Ph.D. at the UT Jackson School of Geosciences.

The researchers made their discovery by comparing the hyoid bones of extinct dinosaurs, pterosaurs and alligators to the hyoid bones and muscles of modern birds and alligator specimens. Hyoid bones act as anchors for the tongue in most animals, but in birds these bones can extend to the tip. Because extinct dinosaurs are related to crocodiles, pterosaurs and modern birds, comparing anatomy across these groups can help scientists understand the similarities and differences in tongue anatomy and how traits evolved through time and across different lineages.

The comparison process involved taking high-resolution images of hyoid muscles and bones from 15 modern specimens, including three alligators and 13 bird species as diverse as ostriches and ducks, at the Jackson School’s High-Resolution X-Ray Computed Tomography Facility (UTCT). The fossil specimens, most from northeastern China, were scrutinized for preservation of the delicate tongue bones and included small bird-like dinosaurs, as well as pterosaurs and a Tyrannosaurus rex.

The results indicate that hyoid bones of most dinosaurs were like those of alligators and crocodiles — short, simple and connected to a tongue that was not very mobile. Co-author and Jackson School Professor Julia Clarke said that these findings mean that dramatic reconstructions that show dinosaurs with tongues stretching out from between their jaws are wrong.

“They’ve been reconstructed the wrong way for a long time”, Clarke said. “In most extinct dinosaurs their tongue bones are very short. And in crocodilians with similarly short hyoid bones, the tongue is totally fixed to the floor of the mouth.”

Clarke is no stranger to overturning dinosaur conventions. Her 2016 study on dinosaur vocalizations found evidence that large dinosaurs might make booming or cooing sounds, similar to the sounds made by crocodiles and ostriches.

In contrast to the short hyoid bones of crocodiles, the researchers found that pterosaurs, bird-like dinosaurs, and living birds have a great diversity in hyoid bone shapes. They think the range of shapes could be related to flight ability, or in the case of flightless birds such as ostriches and emus, evolved from an ancestor that could fly. The researchers propose that taking to the skies could have led to new ways of feeding that could be tied to diversity and mobility in tongues.

“Birds, in general, elaborate their tongue structure in remarkable ways”, Clarke said. “They are shocking.”

That elaboration could be related to the loss of dexterity that accompanied the transformation of hands into wings, Li said.

“If you can’t use a hand to manipulate prey, the tongue may become much more important to manipulate food”, Li said. “That is one of the hypotheses that we put forward.”

The scientists note one exception linking tongue diversity to flight. Ornithischian dinosaurs — a group that includes Triceratops, ankylosaurs and other plant-eating dinosaurs that chewed their food — had hyoid bones that were highly complex and more mobile, though they were structurally different from those of flying dinosaurs and pterosaurs.

Further research on other anatomical changes that occurred with shifts in tongue function could help improve our knowledge of the evolution of birds, Clarke said, giving an example of how changes in the tongues of living birds are associated with changes in the position of the opening of the windpipe. These changes could in turn affect how birds breathe and vocalize.

However, the researchers note that the fossil record as yet can’t pin down when these changes to the windpipe occurred.

“There is more work to be done,” Li said.

The study was funded by the Chinese Academy of Sciences, The University of Texas at Austin, the Smithsonian Institution and the Gordon and Betty Moore Foundation.

Advertisements

How primates got fingernails, new research


This 2016 video says about itself:

Nails evolved from claws roughly 50 million years ago. Why did this happen and what purpose do nails serve?

Oldest evidence of nails in modern primates: “From hot pink to traditional French and Lady Gaga‘s sophisticated designs, manicured nails have become the grammar of fashion. Scientists have now recovered and analyzed the oldest fossil evidence of fingernails in modern primates, confirming the idea nails developed with small body size and disproving previous theories nails evolved with an increase in primate body size.” Read more here.

“Which came first, the nail or the claw? The answer is unclear, but researchers have discovered a clue: an early primate that had a toe bone with features of both a grooming claw and a nail. A fossil of the 47-million-year-old primate, Notharctus tenebrosus, had a lemur-like grooming claw on its second digit, but it was flattened, a bit like a nail, according to a new study in the journal PLoS One.” Read more here.

Evidence for a Grooming Claw in a North American Adapiform Primate: Implications for Anthropoid Origins: “Among fossil primates, the Eocene adapiforms have been suggested as the closest relatives of living anthropoids (monkeys, apes, and humans). Central to this argument is the form of the second pedal digit. Extant strepsirrhines and tarsiers possess a grooming claw on this digit, while most anthropoids have a nail. While controversial, the possible presence of a nail in certain European adapiforms has been considered evidence for anthropoid affinities.” Read more here.

From the University of Florida in the USA:

Fossils show ancient primates had grooming claws as well as nails

Why don’t we have them? Maybe because we have each other

June 20, 2018

Humans and other primates are outliers among mammals for having nails instead of claws. But how, when and why we transitioned from claws to nails has been an evolutionary head-scratcher.

Now, new fossil evidence shows that ancient primates — including one of the oldest known, Teilhardina brandti — had specialized grooming claws as well as nails. The findings overturn the prevailing assumption that the earliest primates had nails on all their digits and suggest the transition from claws to nails was more complex than previously thought.

“We had just assumed nails all evolved once from a common ancestor, and in fact, it’s much more complicated than that,” said Jonathan Bloch, study co-author and Florida Museum of Natural History curator of vertebrate paleontology at the University of Florida.

The findings are scheduled to be published today in the Journal of Human Evolution.

Grooming in mammals is not just about looking good. Thick body hair is a haven for ticks, lice and other parasites — possible health threats, as well as nuisances. Having a specialized claw for removing pests would be an evolutionary advantage, said Doug Boyer, an associate professor in the department of evolutionary anthropology at Duke University and the study’s lead author.

It’s one that has been retained in many primates. Lemurs, lorises, galagoes and tarsiers have nails on most of their digits and grooming claws on their second — and in tarsiers, second and third — toes.

So, why did the ancestors of monkeys, apes and humans lose their grooming claws? One possible answer: because we have each other.

“The loss of grooming claws is probably a reflection of more complex social networks and increased social grooming”, Boyer said. “You’re less reliant on yourself.”

This could explain why more solitary monkey species, such as titi and owl monkeys, have re-evolved a grooming claw, he said.

Researchers had thought grooming claws likely developed independently several times along the lines that gave rise to living primates. But these fossils suggest grooming claws were hallmark features of the earliest primates, dating back at least 56 million years.

They also come from five different genera of ancient primates that belonged to the omomyoids, the ancestors of monkeys, apes, humans and tarsiers — not the branch of primates that gave rise to lemurs, lorises and galagoes.

In 2013, Boyer was at the University of California Museum of Paleontology, sifting through sediment collected in Wyoming several decades earlier, when he found several curious primate fossils. They were distal phalanges, the bones at the tips of fingers and toes, from omomyoids. The shape of these bones reveals whether they support a claw or nail. Bones topped with a claw mimic its narrow, tapered structure while bones undergirding a nail are flat and wide. The distal phalanges that Boyer discovered looked like they belonged to animals with grooming claws.

“Prior to this study, no one knew whether omomyoids had grooming claws”, Boyer said. “Most recent papers came down on the side of nails.”

Meanwhile, Bloch, picking through collections recently recovered from Bighorn Basin, Wyoming, came across what looked like a “strange, narrow nail” bone. But when he compared it to modern primates, “it looked just like a tarsier grooming claw.” Smaller than a grain of rice, it matched the proportions of Teilhardina brandti, a mouse-sized, tree-dwelling primate.

Bloch and Boyer had co-authored a 2011 study describing the first fossil evidence of nails in Teilhardina. At the time, they believed the primate had nails on all its digits. Now, fossils were making them reevaluate their assumptions, not only about Teilhardina, but other omomyoids.

On the off-chance that they could add one more ancient primate to the growing list of claw-bearers, the pair drove out to Omomys Quarry, Wyoming, once inhabited by another genus of omomyoid, Omomys.

“We spent a day combing that site, never expecting to find something as tiny and delicate as a grooming claw,” Boyer said.

The team picked one right off the surface. They had found grooming claws at three independent sites from omomyoids spanning about 10 million years in the fossil record.

“That was the last nail in the coffin”, Boyer said.

Why did primates develop nails at all? The question is a contentious one, but Bloch and Boyer think the transition away from claws could have mirrored changes in primate movement. As we ramped up climbing, leaping and grasping, nails might have proven more practical than claws, which could snag or get in the way.

Grooming claws might seem insignificant, but they can provide crucial insights into ancient primates, many of which are known only from fossil teeth, Bloch said. These tiny claws offer clues about how our earliest ancestors moved through their environment, whether they were social or solitary and what their daily behavior was like.

“We see a bit of ourselves in the hands and feet of living primates”, Bloch said. “How they got this way is a profoundly important part of our evolutionary story.”

Sponge-like Cambrian fossil discovery


Allonia nuda. Credit: Derek Siveter/Tom Harvey/Peiyun Cong

From the University of Leicester in England:

Strange sponge-like fossil creature from half a billion years ago

June 19, 2018

Summary: A discovery of a new species of sponge-like fossil from the Cambrian Period sheds light on early animal evolution.

Scientists have discovered the fossil of an unusual large-bodied sponge-like sea-creature from half a billion years ago.

The creature belongs to an obscure and mysterious group of animals known as the chancelloriids, and scientists are unclear about where they fit in the tree of life.

They represent a lineage of spiny tube-shaped animals that arose during the Cambrian evolutionary “explosion” but went extinct soon afterwards. In some ways they resemble sponges, a group of simple filter-feeding animals, but many scientists have dismissed the similarities as superficial.

The new discovery by a team of scientists from the University of Leicester, the University of Oxford and Yunnan University, China, adds new evidence that could help solve the mystery.

The researchers have published their findings in the Royal Society journal Proceedings of the Royal Society B. The Leicester authors are Tom Harvey, Mark Williams, David Siveter & Sarah Gabbott.

The new species, named Allonnia nuda, was discovered in the Chengjiang deposits of Yunnan Province, China. It was surprisingly large in life (perhaps up to 50 cm or more) but had only a few very tiny spines. Its unusual “naked” appearance suggests that further specimens may be “hiding in plain sight” in fossil collections, and shows that this group was more diverse than previously thought.

Furthermore, the new species holds clues about the pattern of body growth, with clear links to modern sponges. It is too soon to say the mystery has been solved, but the discovery highlights the central role of sponge-like fossils in the debate over earliest animal evolution.

Dr Tom Harvey, from the University of Leicester’s School of Geography, Geology and the Environment, explained: “Fossil chancelloriids were first described around 100 years ago, but have resisted attempts to place them in the tree of life. We argue that their pattern of body growth supports a link to sponges, reinvigorating an old hypothesis. We’re not suggesting that it’s “case closed” for chancelloriids, but we hope our results will inspire new research into the nature of the earliest animals.”

Dr Peiyun Cong, from the Yunnan Key Laboratory for Palaeobiology, Kunming, China, and The Natural History Museum, UK, added: “The Chengjiang deposits of Yunnan Province continue to reveal surprising new fossils we could hardly have imagined. Together, they provide a crucial snapshot of life in the oceans during the Cambrian explosion.”

Ancient Precambrian animals named after Attenborough, Obama


This 14 November 2014 video says about itself:

The fossils of the first animal can be found in the Ediacara Hills in South Australia. This animal is called Dickinsonia. It was a cushion like creature that lay on the seafloor. Its size ranged from a penny to a bath mat. It crept around very slowly to look for food.

From the University of California Riverside in the USA:

Two new creatures discovered from dawn of animal life

June 18, 2018

Earth’s first complex animals were an eclectic bunch that lived in the shallow oceans between 580-540 million years ago.

The iconic Dickinsonia — large flat animals with a quilt-like appearance — were joined by tube-shaped organisms, frond-like creatures that looked more like plants, and several dozen other varieties already characterized by scientists.

Add to that list two new animals discovered by a UC Riverside-led team of researchers:

Obamus coronatus, a name that honors President Barack Obama’s passion for science. This disc-shaped creature was between 0.5-2 cm across with raised spiral grooves on its surface. Obamus coronatus did not seem to move around, rather it was embedded to the ocean mat, a thick layer of organic matter that covered the early ocean floor.

Attenborites janeae, named after the English naturalist and broadcaster Sir David Attenborough for his science advocacy and support of paleontology. This tiny ovoid, less than a centimeter across, was adorned with internal grooves and ridges giving it a raisin-like appearance.

The discovery of Obamus coronatus was published online June 14 in the Australian Journal of Earth Sciences, or AJES, and the Attenborites janeae paper is forthcoming in the same journal. The studies were led by Mary Droser, a professor of paleontology in UCR’s Department of Earth Sciences. Both papers will be included in print in a 2019 thematic AJES issue focusing on South Australia’s Flinders Ranges region, where the discoveries were made.

Part of the Ediacara Biota, the soft-bodied animals are visible as fossils cast in fine-grained sandstone that have been preserved for hundreds of millions of years. These Precambrian lifeforms represent the dawn of animal life and are named after the Ediacara Hills in the Flinders Ranges, the first of several areas in the world where they have been found.

In the hierarchical taxonomic classification system, the Ediacara Biota are not yet organized into families, and little is known about how they relate to modern animals. About 50 genera have been described, which often have only one species.

“The two genera that we identified are a new body plan, unlike anything else that has been described”, Droser said. “We have been seeing evidence for these animals for quite a long time, but it took us a while to verify that they are animals within their own rights and not part of another animal.”

The animals were glimpsed in a particularly well-preserved fossil bed described in another paper published by Droser’s group that will be included in the Flinders Ranges issue of AJES. The researchers dubbed this fossil bed “Alice’s Restaurant Bed”, a tribute to the Arlo Guthrie song and its lyric, “You can get anything you want at Alice’s Restaurant.”

“I’ve been working in this region for 30 years, and I’ve never seen such a beautifully preserved bed with so many high quality and rare specimens, including Obamus and Attenborites”, Droser said. “The AJES issue on the Flinders Ranges will support South Australia’s effort to obtain World Heritage Site status for this area, and this new bed demonstrates the importance of protecting it.”

Prehistoric panda discovery in China


This 18 June 2018 video is called Oldest Known Giant Panda Fossil Found In China.

From ScienceDaily:

22,000-year-old panda from cave in Southern China belongs to distinct, long-lost lineage

June 18, 2018

Researchers who’ve analyzed ancient mitochondrial (mt)DNA isolated from a 22,000-year-old panda found in Cizhutuo Cave in the Guangxi Province of China — a place where no pandas live today — have revealed a new lineage of giant panda. The report, published in Current Biology on June 18, shows that the ancient panda separated from present-day pandas 144,000 to 227,000 years ago, suggesting that it belonged to a distinct group not found today.

The newly sequenced mitochondrial genome represents the oldest DNA evidence from pandas.

“Using a single complete mtDNA sequence, we find a distinct mitochondrial lineage, suggesting that the Cizhutuo panda, while genetically more closely related to present-day pandas than other bears, has a deep, separate history from the common ancestor of present-day pandas”, says Qiaomei Fu from the Chinese Academy of Sciences. “This really highlights that we need to sequence more DNA from ancient pandas to really capture how their genetic diversity has changed through time and how that relates to their current, much more restricted and fragmented habitat.”

Very little has been known about pandas’ past, especially in regions outside of their current range in Shaanxi province or Gansu and Sichuan provinces. Evidence suggests that pandas in the past were much more widespread, but it’s been unclear how those pandas were related to pandas of today.

In the new study, the researchers used sophisticated methods to fish mitochondrial DNA from the ancient cave specimen. That’s a particular challenge because the specimen comes from a subtropical environment, which makes preservation and recovery of DNA difficult.

The researchers successfully sequenced nearly 150,000 DNA fragments and aligned them to the giant panda mitochondrial genome reference sequence to recover the Cizhutuo panda’s complete mitochondrial genome. They then used the new genome along with mitochondrial genomes from 138 present-day bears and 32 ancient bears to construct a family tree.

Their analysis shows that the split between the Cizhutuo panda and the ancestor of present-day pandas goes back about 183,000 years. The Cizhutuo panda also possesses 18 mutations that would alter the structure of proteins across six mitochondrial genes. The researchers say those amino acid changes may be related to the ancient panda’s distinct habitat in Guangxi or perhaps climate differences during the Last Glacial Maximum.

The findings suggest that the ancient panda’s maternal lineage had a long and unique history that differed from the maternal lineages leading to present-day panda populations. The researchers say that their success in capturing the mitochondrial genome also suggests that they might successfully isolate and analyze DNA from the ancient specimen’s much more expansive nuclear genome.

“Comparing the Cizhutuo panda’s nuclear DNA to present-day genome-wide data would allow a more thorough analysis of the evolutionary history of the Cizhutuo specimen, as well as its shared history with present-day pandas”, Fu says.

Dinosaur age crocodilians, new research


This video says about itself:

4 May 2018

Evolution of crocodiles: Of all the reptiles alive today, crocodiles and alligators may be the least changed from their prehistoric forebears of the late Cretaceous period, over 65 million years ago—although the even earlier crocodiles of the Triassic and Jurassic periods sported some distinctly un-crocodile-like features, such as bipedal postures and vegetarian diets.

Along with pterosaurs and dinosaurs, crocodiles were an offshoot of the archosaurs, the “ruling lizards” of the early to middle Triassic period; needless to say, the earliest dinosaurs and the earliest crocodiles resembled one another a lot more than either resembled the first pterosaurs, which also evolved from archosaurs.

1. Xilousuchus
250,000,000 bc – 200,000,000 bc
2. Phytosaur
228,000,000 bc – 199,000,000 bc
3. Erpetosuchus
200,000,000 bc
4. Sarcosuchus
110,000,000 bc
5. Stomatosuchus
100,000,000 bc – 95,000,000 bc
6. Deinosuchus
80,000,000 bc
7. Champsosaurus [not a crocodile, though looking like one]
70,000,000 bc – 50,000,000 bc
8. Cretaceous-Paleogene Extinction Event
65,000,000 bc
9. Crocodylidae (Modern day crocodile)
55,000,000 bc – Present
10. Quinkana
23,000,000 bc – 40,000 bc
11. Crocodylus thorbjarnarsoni
4,200,000 bc

From the University of the Witwatersrand in South Africa:

In the gaping mouth of ancient crocodiles

As an apex predator, the crocodile’s mode of attack — its mouth — had humble beginnings

June 18, 2018

Summary: A new study has endeavoured to further explore the mouth of one of the earliest occurring and least understood groups of crocodilians, the shartegosuchids.

The mouth of today’s crocodilians inspires fear and awe, with their wide gape and the greatest known bite force in the vertebrate animal kingdom. However, this apex predator of today and its modus of attack (its mouth) had humble beginnings.

The very earliest crocodilians were very different to the beasts we know well today, they were much smaller bodied, slender and had longer legs. It is speculated that they led a much different lifestyle to the crocodiles we all know and fear today.

A new study by a team of international experts, led by University of Witwatersrand PhD candidate Kathleen Dollman and Professor Jonah Choiniere published today in the American Museum Novitates, endeavoured to further explore the mouth of one of the earliest occurring and least understand groups of crocodilians, the shartegosuchids.

In 2010, Choiniere was a part of a field team working in the Late Jurassic (±160 mya) exposures in the western Gobi in Mongolia, when he found the fossil of a small snout of a shartegosuchid. This work was co-authored by researchers based at the American Museum of Natural History, the George Washington University and the Institute for Vertebrate Palaeontology and Palaeoanthropology.

The snout was later CT scanned at the American Museum of Natural History, exposing an unusual, closed secondary palate. Crocodilians are one of only a few groups of animals that evolve a completely closed, bony secondary palate (along with turtles and mammals). A closed secondary palate has many biological implications for crocodilians, including breathing whilst under water and reinforcing the skull to allow for their incredible bite force.

This study showed that these early crocodilians, the shartegosuchids, are important because they evolved a completely closed secondary palate much earlier than previously thought. This is an interesting example of convergent evolution, whereby a similar feature evolves independently in two completely unrelated groups. The advent of a convergent evolutionary event allows scientists to test questions about why that feature evolved and even the function of that feature which in this case is the first step in understanding the purpose of a closed secondary palate in crocodilians.

“I was surprised to find that there were many features in the palate and snout that were completely different between shartegosuchids and extant crocodilians,” says Dollman. Shartegosuchids have a thickened and sculptured palate together with a tall and short rostrum, whereas extant crocodilians have a smooth palate with a long and broad rostrum.

“We would expect to see the same palatal structures and snout shapes in both shartegosuchids and extant crocodiles if they were using it for similar functions and had evolved a closed palate for similar reasons”, says Dollman. “The observed differences tell us that shartegosuchids likely had predation practices to which there is no modern analogue in crocodilians.”

“It’s been nearly 10 years since we collected this fossil after driving 5 days across the Gobi Desert,” said Choiniere, “and I am delighted that it’s formed a part of Kathleen’s PhD.”

Dinosaur age and modern frog discoveries


This 14 June 2018 video says about itself:

Frogs trapped in amber for 99 million years are giving a glimpse of a lost world. The tiny creatures have been preserved in sticky tree resin from the later part of the Age of the Dinosaurs.

From the Florida Museum of Natural History in the USA:

Amber fossils provide oldest evidence of frogs in wet, tropical forests

June 14, 2018

Summary: 99-million-year-old amber fossils from Myanmar provide the earliest evidence of frogs in wet, tropical forests.

About 99 million years ago, a tiny juvenile frog in present-day Myanmar was suddenly trapped in sap with a beetle, perhaps its intended next meal.

Unlucky for the frog, but lucky for science.

An extinct species now named Electrorana limoae, it’s one of four fossils that provide the earliest direct evidence of frogs living in wet, tropical forests and are the oldest-known examples of frogs preserved in amber.

“It’s almost unheard of to get a fossil frog from this time period that is small, has preservation of small bones and is mostly three-dimensional. This is pretty special,” said David Blackburn, study co-author and the associate curator of herpetology at the Florida Museum of Natural History. “But what’s most exciting about this animal is its context. These frogs were part of a tropical ecosystem that, in some ways, might not have been that different to what we find today — minus the dinosaurs.”

The findings and species description were published today in Nature’s Scientific Reports.

Frogs have been around for at least 200 million years, but glimpsing their early heyday is tough. Often small and lightly built, frogs don’t tend to preserve well. The frog fossil record skews toward more robust species from arid, seasonal environments, although the bulk of frog diversity today lives in tropical forests.

“Ask any kid what lives in a rainforest, and frogs are on the list”, Blackburn said. “But surprisingly, we have almost nothing from the fossil record to say that’s a longstanding association.”

The amber deposits of northern Myanmar in Southeast Asia provide a unique record of ancient forest ecosystems, with fossil evidence of mosses, bamboo-like plants, aquatic spiders and velvet worms. The discovery of Electrorana and the other fossils, the first frogs to be recovered from these deposits, help add to our understanding of frogs in the Cretaceous period, showing they have inhabited wet, tropical forests for at least 99 million years.

Frogs in amber are quite rare, with previous examples found in the Dominican Republic and Mexico and dating back only about 40 million and 25 million years, respectively.

Less than an inch long, Electrorana is the most well-preserved of the group. Clearly visible in the amber are the frog’s skull, its forelimbs, part of its backbone, a partial hind limb and the unidentified beetle. The other amber fossils contain two hands and an imprint of a frog that likely decayed inside the resin.

But Electrorana raises more questions than it answers, Blackburn said.

Many characteristics herpetologists use to discern details of a frog’s life history and determine how it’s related to other frogs — wrist bones, the pelvis, hip bones, the inner ear, the top of the backbone — are either missing or were not yet fully developed in the juvenile frog.

The existing bones provide clues about Electrorana’s possible living relatives, Blackburn said, but the results are puzzling: Species that have similar features include fire-bellied toads and midwife toads — Eurasian species that live in temperate, not tropical, ecosystems.

Gathering CT skeletal data for both living and extinct frogs, one of Blackburn’s long-term projects, could help illuminate ancient evolutionary relationships, possibly clarifying how Electrorana fits into the frog tree of life.

In the meantime, Blackburn nurtures the hope that other frogs in amber will be discovered, making Electrorana more than a one-hit wonder.

“We don’t have a lot of single-species frog communities in forests. It seems extremely unlikely that there’s only one. There could be a lot more fossils coming.”

In a new study, researchers have investigated how the endocrine-disrupting substance linuron affects reproduction in the West African clawed frog, Xenopus tropicalis. The scientists found that linuron, which is used as a pesticicide, impaired the males’ fertility, and that tadpoles developed ovaries instead of testicles to a greater extent, which caused a female-biased sex ratio: here.