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Tag: Paleontology

  • Fossilized Bee Nests Inside Skeletons Are Unlike Anything We’ve Seen Before

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    Scientists studying a Caribbean island cave have unearthed something unexpected: ancient bees very much unlike the hive-dwelling insects we’re most familiar with.

    For the first time ever, paleontologists have found fossil traces of burrowing bees nesting inside the buried bones of other animals. These fossils, thousands of years old, are the end result of a macabre life cycle that involved ancient rodents and giant barn owls. And they might also teach us a few lessons about bees today, the researchers say.

    “I think the most important outcome is to show how diverse the nesting behavior of bees can be,” study researcher Lazaro Viñola Lopez told Gizmodo.

    A “fortuitous” discovery

    Viñola Lopez was working as a doctoral student for the Florida Museum of Natural History when he helped excavate the fossils from inside the cave on the island of Hispaniola (the cave is located on the eastern half of the island, owned by the Dominican Republic). But neither he nor his colleagues were planning to make such a find.

    “The discovery was very fortuitous. We were looking for primates, rodents, lizards, and other vertebrates for our work on late Quaternary extinctions in the islands associated with humans and climatic changes,” he said. “We weren’t looking for any insects because they usually don’t preserve in that kind of environment.”

    The cave, named Cueva de Mono, contained thousands of fossils belonging to hutia, rodents related to the guinea pig. This discovery was amazing enough, given how rare hutia fossils were to find in the area. But Viñola Lopez also noticed that one of the fossils, a specimen of hutia mandibles, had an unusual smoothness to it.

    Viñola Lopez didn’t immediately dig deeper into his potential finding, and there were some bumps along the way. Based on his earlier work with dinosaur fossils, he initially speculated the hutia remains were used by wasps to build their nests, but the features of such nests didn’t quite match up with what he found.

    Eventually though, he realized these remains were likely used by a different insect, an ancient species of burrowing bee, named Osnidum almontei, that lived thousands of years ago. Thanks to later trips inside the cave to recover more fossils, they also found evidence of these nests inside the vertebra of a hutia and the pulp cavity of a sloth tooth (sloths used to live in the Caribbean islands, but were largely wiped out by human activity).

    The team’s findings were published Tuesday in the Proceedings of the Royal Society B Biological Sciences.

    Unusual bees

    Though we most commonly think of bees as social insects that build elaborate nests in plain sight, Viñola Lopez notes that most bee species are solitary and use a wide range of structures and materials for nesting. But while these ancient bees seem to share a lot in common with modern counterparts, they also stand out in important and mysterious ways.

    “The bees that created these traces are similar to other bees in that they nested in the ground, but differ from all other known species in that they regularly used chambers in buried bones (such as tooth sockets),” he said. Another key distinction is the cave setting of these fossils. There’s only been one other documented instance of burrowing bees using a cave for their nests, according to the researchers, and that didn’t involve the bees using another animal’s fossil remains.

    As best as they can tell, the cave was home to a population of ancient barn owls that also regularly used it as a dumping ground for the hutia they hunted. The owls might have taken the rodents back home for dinner or sometimes just pooped them out from a meal on-the-go; these remains then later proved to be an appealing site for the bees’ nesting. And while much of the surrounding area is unsuitable for these insects, the cave and others like it might have contained enough built-up soil for the bees to rely on for their nests.

    Aside from learning more about bees, the team’s research has also taught them to be more cautious.

    “It changed how we look at and prepare fossils from these cave deposits in the Dominican Republic. Now we take much more care before cleaning them to make sure we don’t destroy any other interesting behavior of ancient insects hiding in the sediment inside the fossils,” he said.

    The ancient cave bees aren’t the only discovery the researchers are hoping to make. They’re already working to describe the many other fossils recovered from the cave, which should include never-before-characterized species of mammals, reptiles, and birds.

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    Ed Cara

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  • Brazilian physician hails love of paleontology that led to major ancient reptile discovery

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    By Diego Vara

    PARAISO DO SUL, Brazil (Reuters) -When physician Pedro Lucas Porcela Aurelio unearthed a fossil in Brazil’s southern Rio ​Grande do Sul state in 2014, he could barely imagine his discovery ‌would later help scientists better understand the rise of early reptiles.

    Research identified that fossil as belonging to a ‌four-legged ancient reptile, roughly the size of a small dog and with a long tail, dating back some 237 million years – making it one of the world’s oldest.

    Finding the fossil of the species formally named Gondwanax paraisensis was a result of ⁠Aurelio’s longstanding love of ‌paleontology, which he says has become much more than a hobby since he first started going on field trips in 1996.

    “I adopted ‍it as part of my life,” the 66-year-old nephrologist from the town of Paraiso do Sul, where he unearthed the fossil, told Reuters.

    He donated it to a local ​university, prompting new research that paleontologist Rodrigo Temp Muller detailed in a study published ‌last year.

    Unearthed in a rock layer dating back to the Triassic period, between 252 million and 201 million years ago, the fossil comes from the time when dinosaurs as well as mammals, crocodiles, turtles and frogs first arose.

    “How can I touch millions of years? When I held it, I would sweat from emotion,⁠” said Aurelio.

    Muller said that many fossils currently ​found in local collections were discovered by Aurelio, ​praising his love for paleontology and awareness of fossil heritage as inspiring for both professionals and students.

    While still working as a doctor, Aurelio vowed ‍to keep searching for ⁠fossils.

    “Here I can rub my hands in Triassic sediments. And honestly, I prefer that to washing blood off my hands,” he said. ⁠”I’ll continue field trips until the day I’m gone. As long as I have ‌strength, I’ll keep going.”

    (Reporting by Sergio Queiroz ‌and Diego Vara; Editing by Bill Berkrot)

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  • Rediscovered Fossil Redraws the Map of Woolly Mammoth Territory

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    Sometimes the greatest discoveries are actually rediscoveries. In Canada, for example, researchers revealed North America’s most northeasterly woolly mammoth find after taking a second look at a mammoth tooth first discovered in 1878.

    In a study published last month in the journal Canadian Science Publishing, researchers analyzed a worn mammoth tooth found almost 150 years ago on an island in Nunavut—a northern Canadian territory. The results have led the team to reclassify the tooth, formerly believed to have belonged to a Columbian mammoth, as the remains of an older cold-adapted woolly mammoth. The research sheds light on this individual in its final days and reveals woolly mammoths reached significantly farther east than previously thought.

    A prehistoric tooth

    “On the basis of morphology, we cautiously identify the tooth as the worn stump of the third left upper molar of a woolly mammoth (Mammuthus primigenius),” the researchers wrote in the study.

    They re-examined the tooth’s morphology, dated the fossil, and conducted isotope analyses. Simply put, isotopes are different versions of the same element, and experts use stable isotope analysis to investigate ancient diets, among other things. Louis-Philippe Bateman, lead author of the study and a graduate student in McGill University’s Department of Biology, compares isotopic analysis to “high-stakes dentistry on precious fossil remains.”

    The isotopic tests revealed that the mammoth consumed standard Ice Age vegetation, grasses, and other plants, even though it likely lived during an interglacial period (a time between ice ages free of large ice sheets) between 130,000 and 100,000 years ago, when the area had similar temperatures to today’s. The tests also showed higher nitrogen levels than expected, suggesting that the animal may have suffered from malnutrition at the end of its life.

    Peek-a-mammoth

    “Now that we know woolly mammoths likely ranged here, it’s very tempting to go out and look for some more. They can turn up in the most unexpected of places!” Louis-Philippe Bateman added. On a broader scale, the paper underscores museum collections’ long-lasting value. “A specimen kept for almost 150 years still has secrets to reveal,” Bateman added. “Studying them can give us insights into how organisms evolve and respond to climate change.”

    In other words, museum collections have the potential to be a gift that keeps on giving. On a different note, I don’t know why anyone would be surprised at the idea of a woolly mammoth roaming farther than expected. After all, Manfred (aka Manny, everyone’s favorite mammoth in the animated movie Ice Age) certainly went out of his way to return a human child to its family. Maybe the owner of this tooth was on a similar mission.

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    Margherita Bassi

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  • PHOTOS: 66 million-year-old dinosaur ‘mummy’ skin was actually a perfect clay mask

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    In the badlands of eastern Wyoming, the Lance Formation is a trove of prehistoric fossils. And one area in particular — a region less than 10 kilometers (6 miles) across — has provided scientists with at least half a dozen remarkably well-preserved dinosaur specimens complete with details of scaly skin, hooves and spikes.The paleontologist Dr. Paul Sereno and his colleagues dub it “the mummy zone” in a new study that aims to explain why this particular area has given rise to so many amazing finds and define exactly what a dinosaur “mummy” is.In the early 1900s, a fossil hunter named Charles Sternberg found two specimens of a large duck-billed dinosaur, Edmontosaurus annectens, in the Lance Formation. The skeletons were so pristine that Sternberg, along with H.F. Osborn, a paleontologist at New York’s American Museum of Natural History, could make out what appeared to be large swaths of skin with discernible scales and a fleshy crest that seemed to run along the reptile’s neck.Sereno, lead study author and a professor of organismal biology and anatomy at the University of Chicago, described the initial discovery as “the greatest dinosaur mummy — until maybe the juvenile that we found” in the year 2000.Separated by nearly a century, Sereno and his team’s find shared common traits with Sternberg’s: The skeletons were preserved in three-dimensional poses and showed clear evidence of skin and other attributes that don’t usually survive 66 million years in the ground. “Osborn said in 1912 he knew that it wasn’t actual, dehydrated skin, like in Egyptian mummies,” Sereno said. “But what was it?”Whatever it was, “we actually didn’t know how it was preserved,” he said. “It was a mystery.”The new research puts that mystery to rest and can help paleontologists find, recognize and analyze future mummy finds for tiny clues into how giant dinosaurs really looked.A dinosaur death cast in claySereno and his collaborators used CT scanning, 3D imaging, electron microscopy and X-ray spectroscopy to analyze two Edmontosaurus mummies they discovered in the Lance Formation in 2000 and 2001 — a juvenile and a young adult. “We looked and we looked and we looked, we sampled and we tested, and we didn’t find any” remnants of soft tissue, Sereno said.What the team found instead was a thin layer of clay, less than one-hundredth of an inch thick, which had formed on top of the animals’ skin. “It’s so real-looking, it’s unbelievable,” he said.Whereas Sternberg and Osborn referred to the “impression” of skin in their specimens, Sereno’s paper proposes an alternate term — “rendering” — which he argues is more precise.The study lays out the conditions that would produce such a rendering. In the Late Cretaceous Period, when Edmontosaurus roamed what is now the American West, the climate cycled between drought and monsoon rains. Drought has been determined to have been the cause of death of the original mummy found by Sternberg and described by Osborn, and of other animals whose fossils were found nearby. Assuming the same is true of the new specimens, the carcasses would have dried in the sun in a week or two.Then, a flash flood buried the bodies in sediment. The decaying carcasses would have been covered by a film of bacteria, which can electrostatically attract clay found in the surrounding sediment. The wafer-thin coating of clay remained long after the underlying tissues decayed completely, retaining their detailed morphology and forming a perfect clay mask.“Clay minerals have a way of attracting to and sticking onto biological surfaces, ensuring a molding that can faithfully reproduce the outermost surfaces of a body, such as skin and other soft tissues,” said Dr. Anthony Martin, professor of practice in the department of environmental sciences at Emory University in Atlanta, who was not involved in the research. “So it makes sense that these clays would have formed such fine portraits of dinosaurs’ scales, spikes and hooves.”Dr. Stephanie Drumheller-Horton, a vertebrate paleontologist at the University of Tennessee, Knoxville, who also was not involved in the study, is an expert in taphonomy, which she described as “the study of everything that happens to an organism from when it dies until when we find it.” She is particularly interested in how these fossils formed.“Dinosaur mummies have been known for over one hundred years, but there has definitely been more emphasis on describing their skin and less on understanding how they fossilized in the first place,” she said via email. “If we can understand how and why these fossils form, we can better target where to look to potentially find more of them.”A detailed portrait of a duck-billed dinosaurTogether, the two more recently unearthed mummies allowed Sereno and his team to create a detailed update of what Edmontosaurus probably looked like.According to their analyses, the dinosaur, which could grow to over 12 meters (40 feet) long, had a fleshy crest along the neck and back and a row of spikes running down the tail. The creature’s skin was thin enough to produce delicate wrinkles over the rib cage and was dotted with small, pebble-like scales.The clay mask revealed that the animal had hooves, a trait previously preserved only in mammals. That makes it the oldest land animal proven to have hooves and the first known example of a hoofed reptile, Sereno said. “Sorry, mammals, you didn’t invent it,” he joked. “Did we suspect it? Yeah, we suspected it had a hoof from the footprints, but seeing it is believing.”

    In the badlands of eastern Wyoming, the Lance Formation is a trove of prehistoric fossils. And one area in particular — a region less than 10 kilometers (6 miles) across — has provided scientists with at least half a dozen remarkably well-preserved dinosaur specimens complete with details of scaly skin, hooves and spikes.

    The paleontologist Dr. Paul Sereno and his colleagues dub it “the mummy zone” in a new study that aims to explain why this particular area has given rise to so many amazing finds and define exactly what a dinosaur “mummy” is.

    In the early 1900s, a fossil hunter named Charles Sternberg found two specimens of a large duck-billed dinosaur, Edmontosaurus annectens, in the Lance Formation. The skeletons were so pristine that Sternberg, along with H.F. Osborn, a paleontologist at New York’s American Museum of Natural History, could make out what appeared to be large swaths of skin with discernible scales and a fleshy crest that seemed to run along the reptile’s neck.

    Sereno, lead study author and a professor of organismal biology and anatomy at the University of Chicago, described the initial discovery as “the greatest dinosaur mummy — until maybe the juvenile that we found” in the year 2000.

    Separated by nearly a century, Sereno and his team’s find shared common traits with Sternberg’s: The skeletons were preserved in three-dimensional poses and showed clear evidence of skin and other attributes that don’t usually survive 66 million years in the ground. “Osborn said in 1912 he knew that it wasn’t actual, dehydrated skin, like in Egyptian mummies,” Sereno said. “But what was it?”

    Whatever it was, “we actually didn’t know how it was preserved,” he said. “It was a mystery.”

    The new research puts that mystery to rest and can help paleontologists find, recognize and analyze future mummy finds for tiny clues into how giant dinosaurs really looked.

    A dinosaur death cast in clay

    Sereno and his collaborators used CT scanning, 3D imaging, electron microscopy and X-ray spectroscopy to analyze two Edmontosaurus mummies they discovered in the Lance Formation in 2000 and 2001 — a juvenile and a young adult. “We looked and we looked and we looked, we sampled and we tested, and we didn’t find any” remnants of soft tissue, Sereno said.

    What the team found instead was a thin layer of clay, less than one-hundredth of an inch thick, which had formed on top of the animals’ skin. “It’s so real-looking, it’s unbelievable,” he said.

    Whereas Sternberg and Osborn referred to the “impression” of skin in their specimens, Sereno’s paper proposes an alternate term — “rendering” — which he argues is more precise.

    The study lays out the conditions that would produce such a rendering. In the Late Cretaceous Period, when Edmontosaurus roamed what is now the American West, the climate cycled between drought and monsoon rains. Drought has been determined to have been the cause of death of the original mummy found by Sternberg and described by Osborn, and of other animals whose fossils were found nearby. Assuming the same is true of the new specimens, the carcasses would have dried in the sun in a week or two.

    Then, a flash flood buried the bodies in sediment. The decaying carcasses would have been covered by a film of bacteria, which can electrostatically attract clay found in the surrounding sediment. The wafer-thin coating of clay remained long after the underlying tissues decayed completely, retaining their detailed morphology and forming a perfect clay mask.

    “Clay minerals have a way of attracting to and sticking onto biological surfaces, ensuring a molding that can faithfully reproduce the outermost surfaces of a body, such as skin and other soft tissues,” said Dr. Anthony Martin, professor of practice in the department of environmental sciences at Emory University in Atlanta, who was not involved in the research. “So it makes sense that these clays would have formed such fine portraits of dinosaurs’ scales, spikes and hooves.”

    Dr. Stephanie Drumheller-Horton, a vertebrate paleontologist at the University of Tennessee, Knoxville, who also was not involved in the study, is an expert in taphonomy, which she described as “the study of everything that happens to an organism from when it dies until when we find it.” She is particularly interested in how these fossils formed.

    “Dinosaur mummies have been known for over one hundred years, but there has definitely been more emphasis on describing their skin and less on understanding how they fossilized in the first place,” she said via email. “If we can understand how and why these fossils form, we can better target where to look to potentially find more of them.”

    A detailed portrait of a duck-billed dinosaur

    Together, the two more recently unearthed mummies allowed Sereno and his team to create a detailed update of what Edmontosaurus probably looked like.

    According to their analyses, the dinosaur, which could grow to over 12 meters (40 feet) long, had a fleshy crest along the neck and back and a row of spikes running down the tail. The creature’s skin was thin enough to produce delicate wrinkles over the rib cage and was dotted with small, pebble-like scales.

    mummified dinosaur

    The clay mask revealed that the animal had hooves, a trait previously preserved only in mammals. That makes it the oldest land animal proven to have hooves and the first known example of a hoofed reptile, Sereno said. “Sorry, mammals, you didn’t invent it,” he joked. “Did we suspect it? Yeah, we suspected it had a hoof from the footprints, but seeing it is believing.”

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  • Africans discovered fossils first

    Africans discovered fossils first

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    Newswise — Credit for discovering the first dinosaur bones usually goes to British gentlemen for their finds between the 17th and 19th centuries in England. Robert Plot, an English natural history scholar, was the first of these to describe a dinosaur bone, in his 1676 book The Natural History of Oxfordshire. Over the next two centuries dinosaur palaeontology would be dominated by numerous British natural scientists.

    But our study shows that the history of palaeontology can be traced back much further into the past. We present evidence that the first dinosaur bone may have been discovered in Africa as early as 500 years before Plot’s.

    We’re a team of scientists who study fossils in South Africa. Peering through the published and unpublished archaeological, historical and palaeontological literature, we discovered that there has been interest in fossils in Africa for as long as there have been people on the continent.

    This is not a surprise. Humankind originated in Africa: Homo sapiens has existed for at least 300,000 years. And the continent has a great diversity of rock outcrops, such as the Kem Kem beds in Morocco, the Fayum depression in Egypt, the Rift Valley in east Africa and the Karoo in southern Africa, containing fossils that have always been accessible to our ancestors.

    So it wasn’t just likely that African people discovered fossils first. It was inevitable.

    More often than not, the first dinosaur fossils supposedly discovered by scientists were actually brought to their attention by local guides. Examples are the discovery of the gigantic dinosaurs Jobaria by the Tuaregs in Niger and Giraffatitan by the Mwera in Tanzania.

    Our paper reviews what’s known about African indigenous knowledge of fossils. We list fossils that appear to have long been known at various African sites, and discuss how they might have been used and interpreted by African communities before the science of palaeontology came to be.

    Bolahla rock shelter in Lesotho

    One of the highlights of our paper is the archaeological site of Bolahla, a Later Stone Age rock shelter in Lesotho. Various dating techniques indicate that the site was occupied by the Khoesan and Basotho people from the 12th to 18th centuries (1100 to 1700 AD). The shelter itself is surrounded by hills made of consolidated sediments that were deposited under a harsh Sahara-like desert some 180 million to 200 million years ago, when the first dinosaurs roamed the Earth.

    This part of Lesotho is particularly well known for delivering the species Massospondylus carinatus, a 4 to 6 metre, long-necked and small-headed dinosaur. Fossilised bones of Massospondylus are abundant in the area and were already so when the site was occupied by people in the Middle Ages.

    In 1990, archaeologists working at Bolahla discovered that a finger bone of Massospondylus, a fossil phalanx, had been transported to the cave. There are no fossil skeletons sticking out the walls of the cave, so the only chance that this phalanx ended up there was that someone in the distant past picked it up and carried it to the cave. Perhaps this person did so out of simple curiosity, or to turn it into a pendant or toy, or to use it for traditional healing rituals.

    After heavy rains, it is not unusual that the people in the area discover the bones of extinct species that have been washed out of their mother-rock. They usually identify them as belonging to a dragon-like monster that devours people or even whole houses. In Lesotho, the Basotho call the monster “Kholumolumo”, while in South Africa’s bordering Eastern Cape province, the Xhosa refer to it as “Amagongqongqo”.

    The exact date when the phalanx was collected and transported is unfortunately lost to time. Given the current knowledge, it could have been at any time of occupation of the shelter from the 12th to 18th centuries. This leaves open the possibility that this dinosaur bone could have been collected up to 500 years prior to Robert Plot’s find.

    Early knowledge of extinct creatures

    Most people knew about fossils well before the scientific era, for as far back as collective societal memories can go. In Algeria, for example, people referred to some dinosaur footprints as belonging to the legendary “Roc bird”. In North America, cave paintings depicting dinosaur footprints were painted by the Anasazi people between AD 1000 and 1200. Indigenous Australians identified dinosaur footprints as belonging to a legendary “Emu-man”. To the south, the notorious conquistador Hernan Cortes was given the fossil femur of a Mastodon by the Aztecs in 1519. In Asia, Hindu people refer to ammonites (coiled fossil-sea-shells) as “Shaligrams” and have been worshipping them for more than 2,000 years.

    Claiming credit

    The fact that people in Africa have long known about fossils is evident from folklore and the archaeological record, but we still have much to learn about it. For instance, unlike the people in Europe, the Americas and Asia, indigenous African palaeontologists seem to have seldom used fossils for traditional medicine. We are still unsure whether this is a genuinely unique cultural trait shared by most African cultures or if it is due to our admittedly still incomplete knowledge.

    Also, some rather prominent fossil sites, such as the Moroccan Kem Kem beds and South African Unesco Cradle of Humankind caves, have still not provided robust evidence for indigenous knowledge. This is unfortunate, as fossil-related traditions could help bridge the gap between local communities and palaeontologists, which in turn could contribute preserving important heritage sites.

    By exploring indigenous palaeontology in Africa, our team is putting together pieces of a forgotten past that gives credit back to local communities. We hope it will inspire a new generation of local palaeoscientists to walk in the footsteps of these first African fossil hunters.

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    University of the Witwatersrand, Johannesburg

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  • Fossil plant revealed as a baby turtle fossil.

    Fossil plant revealed as a baby turtle fossil.

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    Newswise — From the 1950s to the 1970s, a Colombian priest named Padre Gustavo Huertas collected rocks and fossils near a town called Villa de Levya. Two of the specimens he found were small, round rocks patterned with lines that looked like leaves; he classified them as a type of fossil plant. But in a new study, published in the journal Palaeontologia Electronica, researchers re-examined these “plant” fossils and found that they weren’t plants at all: they were the fossilized remains of baby turtles.

    “It was truly surprising to find these fossils,” says Héctor Palma-Castro, a paleobotany student at the Universidad Nacional de Colombia.

    The plants in question had been described by Huertas in 2003 as Sphenophyllum colombianum. The fossils come from Early Cretaceous rocks, between 132 and 113 million years ago, during the dinosaurs’ era. Fossils of Sphenophyllum colombianum were surprising at this time and place— the other known members of the genus Sphenophyllum died out more than 100 million years prior. The plants’a ge and locality piqued the interest of Fabiany Herrera, the Negaunee assistant curator of fossil plants at the Field Museum in Chicago, and his student, Palma-Castro.

    “We went to the fossil collection at the Universidad Nacional de Colombia in Bogotá and started looking at the plants, and as soon as we photographed them, we thought, ‘this is weird,’” says Herrera, who has been collecting Early Cretaceous plants from northwestern South America, an area of the world with little paleobotanical work.

    At first glance, the fossils, about 2 inches in diameter, looked like rounded nodules containing the preserved leaves of the plant Sphenophyllum. But Herrera and Palma-Castro noticed key features that weren’t quite right.

    “We spent days searching through wooden cabinets for fossil plants. When we finally found this fossil, deciphering the shape and margin of the leaf proved challenging,” says Palma-Castro.

    “When you look at it in detail, the lines seen on the fossils don’t look like the veins of a plant— I was positive that it was most likely bone,” says Herrera. So he reached out to an old colleague of his, Edwin-Alberto Cadena.

    “They sent me the photos, and I said, “This definitely looks like a carapace’— the bony upper shell of a turtle,” says Cadena, a paleontologist who focuses on turtles and other vertebrates at the Universidad del Rosario in Bogotá. When he saw the scale of the photos, Cadena recalls, “I said, ‘Well, this is remarkable, because this is not only a turtle, but it’s also a hatchling specimen, it’s very, very small.”

    Cadena and his student, Diego Cómbita-Romero of the Universidad Nacional de Colombia, further examined the specimens, comparing them with the shells of both fossil and modern turtles. “When we saw the specimen for the first time I was astonished, because the fossil was missing the typical marks on the outside of a turtle’s shell,” says Cómbita-Romero. It was a little bit concave, like a bowl. At that moment we realized that the visible part of the fossil was the other side of the carapace, we were looking at the part of the shell that is inside the turtle.”

    Details in the turtle’s bones helped the researchers estimate how old it was at death. “Turtle growth rates and sizes vary,” says Cómbita-Romero, so the team looked at features like the thickness of its carapace and the spots where its ribs were knitting together into solid bone. “This is a feature uncommon in hatchlings but observed in juveniles. All this information suggests that the turtle likely died with a slightly developed carapace, between 0 to 1 years old, in a post-hatchling stage,” he says.

    “This is actually really rare to find hatchlings of fossil turtles in general,” says Cadena. “When the turtles are very young, the bones in their shells are very thin, so they can be easily destroyed.”

    The researchers say that the rarity of fossilized baby turtles makes their discovery an important one. “These turtles were likely relatives of other Cretaceous species that were up to fifteen feet long, but we don’t know much about how they actually grew to such giant sizes,” says Cadena.

    The researchers don’t fault Padre Huertas for his mistake— the preserved shells really do resemble many fossil plants. But the features that Huertas thought were leaves and stems are actually the modified rib bones and vertebrae that make up a turtle’s shell. Cómbita-Romero and Palma-Castro nicknamed the specimens as “Turtwig,” after a Pokémon that’s half-turtle, half-plant.

    “In the Pokémon universe, you encounter the concept of combining two or more elements, such as animals, machines, plants, etc. So, when you have a fossil initially classified as a plant that turns out to be a baby turtle, a few Pokémon immediately come to mind. In this case, Turtwig, a baby turtle with a leaf attached to its head,” says Palma-Castro.” In paleontology, your imagination and capacity to be amazed are always put to the test. Discoveries like these are truly special because they not only expand our knowledge about the past but also open a window to the diverse possibilities of what we can uncover.”

    The scientists also note the importance of these fossils in the larger scheme of Colombian paleontology. “We resolved a small paleobotanical mystery, but more importantly, this study shows the need to re-study historical collections in Colombia. The Early Cretaceous is a critical time in land plant evolution, particularly for flowering plants and gymnosperms. Our future job is to discover the forests that grew in this part of the world,” says Herrera.

    This project was supported by the National Geographic Society, grant (EC-96755R-22) Discovering Early Cretaceous Floras from Northern South America & the Negaunee Integrative Research Center, Field Museum.

     

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    Field Museum

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  • Plesiosaurs doubled their neck-length by gaining new vertebrae

    Plesiosaurs doubled their neck-length by gaining new vertebrae

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    BYLINE: Laura Thomas

    Newswise — Plesiosaurs gained their famous long necks rapidly, researchers have shown.

    Their lengthy necks, used for chasing fast-moving fishes, developed quickly over a five million period around 250 million years ago.

    The findings, published today in BMC Ecology and Evolution, and carried out by scientists in China and the UK, show that a species known as pachycephalosaurs lengthened their necks mainly by adding new vertebrae.  One species, Pachycephalosaurs had 25 vertebrae, while some Late Cretaceous plesiosaurs such as Elasmosaurus had as many as 72, and its neck was five times the length of its trunk

    The animals originated in the Early Triassic, four million years after the end-Permian mass extinction wiped out around 90% of Earth’s species and during a time of rapid change following the disaster.

    In the study, the researchers describe a new, short-necked plesiosaur ancestor called Chusaurus xiangensis from the Early Triassic of Hubei Province, China. Its neck has begun to lengthen, but it is only half the length of the trunk of its body compared to 80% or higher in its later relatives.

    “We were lucky enough to find two complete skeletons of this new beast,” said Qi-Ling Liu from the China University of Geosciences in Wuhan, who led the project. “It’s small, less than half a metre long, but this was close to the ancestry of the important group of marine reptiles called Sauropterygia.

    “Our new reptile, Chusaurus, is a pachycephalosaur, one of a group of small marine predators that were very important in the Triassic. I wasn’t sure at first whether it was a pachypleurosaur though because the neck seemed to be too short.”

    “The fossils come from the Nanzhang-Yuan’an Fauna of Hubei,” said Dr Li Tian, also of China University of Geosciences Wuhan, who co-supervised the project. “This has been very heavily studied in recent years as one of the oldest assemblages of marine reptiles from the Triassic. We have good quality radiometreic dates showing the fauna is dated at 248 million years ago.”

    Collaborator Professor Michael Benton of the University of Bristol’s School of Earth Sciences said: “The end-Permian mass extinction had been the biggest mass extinction of all time and only one in twenty species survived.

    “The Early Triassic was a time of recovery and marine reptiles evolved very fast at that time, most of them predators on the shrimps, fishes and other sea creatures. They had originated right after the extinction, so we know their rates of change were extremely rapid in the new world after the crisis.”

    “The pachycephalosaurs lengthened their necks mainly by adding new vertebrae,” said Professor Cheng Long, of the Wuhan Centre of China Geological Survey, a co-supervisor.

    “Normally, vertebrates like reptiles and mammals (and us) have seven neck vertebrae.  Chusaurus already had 17, whereas later pachycephalosaurs had 25. Some Late Cretaceous plesiosaurs such as Elasmosaurus even had 72, and its neck was five times the length of its trunk. With so many vertebrae, these long necks must have been super-snakey and they presumably whipped the neck around to grab fishy prey while keeping the body steady.”

    Dr Tom Stubbs of the Open University UK added: “Not all long-necked animals do it in the same way. Giraffes for example keep the standard seven neck vertebrae, but each one is very long, so they can reach high into the trees. Flamingos also have long necks so they can reach the water to feed, because of their long legs, and they have extra vertebrae, up to twenty, but each one is also long.”

    “Our study shows that pachycephalosaurs doubled the lengths of their necks in five million years, and the rate of increase then slowed down,’ added Dr Ben Moon, also of the University of Bristol. “They had presumably reached some kind of perfect neck length for their mode of life.

    “We think, as small predators, they were probably mainly feeding on shrimps and small fish, so their ability to sneak up on a small shoal, and then hover in the water, darting their head after the fast-swimming prey was a great survival tool. But there might have been additional costs in having a much longer neck, so it stabilised at a length just equal to the length of the trunk.”

     

    The paper:

    ‘Rapid neck elongation in Sauropterygia (Reptilia: Diapsida) revealed by a new basal pachypleurosaur from the Lower Triassic of China’ by Qi-Ling Liu, Long Cheng, Thomas L. Stubbs, Benjamin C. Moon, Michael J. Benton, and Li Tian in BMC Ecology and Evolution.

     

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    University of Bristol

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  • The modern sea spider had started to diversify by the Jurassic, study finds

    The modern sea spider had started to diversify by the Jurassic, study finds

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    BYLINE: Laura Thomas

    Newswise — An extremely rare collection of 160-million-year-old sea spider fossils from Southern France are closely related to living species, unlike older fossils of their kind.

    These fossils are very important to understand the evolution of sea spiders. They show that the diversity of sea spiders that still exist today had already started to form by the Jurassic.

    Lead author Dr Romain Sabroux from the University of Bristol’s School of Earth Sciences, said: “Sea spiders (Pycnogonida), are a group of marine animals that is overall very poorly studied.

    “However, they are very interesting to understand the evolution of arthropods [the group that includes insects, arachnids, crustaceans, centipedes and millipedes] as they appeared relatively early in the arthropod tree of life. That’s why we are interested in their evolution.

    “Sea spider fossils are very rare, but we know a few of them from different periods. One of the most remarkable fauna, by its diversity and its abundance, is the one of La Voulte-sur-Rhône that dates back to the Jurassic, some 160 million years ago.”

    Unlike older sea spider fossils, the La Voulte pycnogonids are morphologically similar (but not identical) to living  species, and previous studies suggested they could be closely related to living sea spider families. But these hypotheses were restricted by the limitation of their observation means. As it was impossible to access what was hidden in the rock fossils, Dr Sabroux and his team travelled to Paris and set out to investigate this question with cutting-edge approaches.

    Dr Sabroux explained: “We used two methods to reinvestigate the morphology of the fossils: X-ray microtomography, to ‘look inside’ the rock, find morphological features hidden inside and reconstruct a 3D model of the fossilised specimen; and Reflectance Transformation Imaging, a picture technic that relies on varied orientation of the light around the fossil to enhance the visibility of inconspicuous features on their surface.

    “From these new insights, we drew new morphological information to compare them with extant species,” explained Dr Sabroux.

    This confirmed that these fossils are close relatives to surviving pycnogonids. Two of these fossils belong to two living pycnogonid families: Colossopantopodus boissinensis was a Colossendeidae while another, Palaeoendeis elmii was an Endeidae. The third species, Palaeopycnogonides gracilis, seems to belong to a family that has disappeared today.

    “Today, by calculating the difference between the DNA sequences of a sample of species, and using DNA evolution models, we are able to estimate the timing of the evolution that bind these species together,“ added Dr Sabroux.

    “This is what we call a molecular clock analysis. But quite like a real clock, it needs to be calibrated. Basically, we need to tell the clock: ‘we know that at that time, that group was already there.’ Thanks to our work, we now know that Colossendeidae, and Endeidae were already ’there’ by the Jurassic.”

    Now, the team can use these minimal ages as calibrations for the molecular clock, and investigate the timing of Pycnogonida evolution. This can help them understand, for example, how their diversity was impacted by the different biodiversity crises that distributes over the Earth history.

    They also plan to investigate other pycnogonid fossil faunae such as the fauna of Hunsrück Slate, in Germany, which dates from the Devonian, some 400 million years ago.

    With the same approach, they will aim to redescribe these species and understand their affinities with extant species; and finally, to replace in the tree of life of Pycnogonida all the pycnogonid fossils from all periods.

    Dr Sabroux added: “These fossils give us an insight of sea spiders living 160 million years ago.

    “This is very exciting when you have been working on the living pycnogonids for years.

    “It is fascinating how these pycnogonids look both very familiar, and very exotic. Familiar, because you can definitely recognize some of the families that still exist today, and exotic because of small differences like the size of the legs, the length of the body, and some other morphological characteristics that you do not find in modern species.

    “Now we look forward to the next fossil discoveries – from the Jurassic and other geological periods – so that we can complete the picture!”

     

    Paper:

    ‘New insights into the sea spider fauna (Arthropoda: Pycnogonida) of La Voulte-sur-Rhône, France (Jurassic: Callovian)’ by Romain Sabroux et al in Papers in Palaeontology.

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    University of Bristol

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  • New pterosaur nicknamed ‘Elvis’ takes flight

    New pterosaur nicknamed ‘Elvis’ takes flight

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    Newswise — A new 145-million-year-old pterosaur (extinct flying reptiles that lived alongside the dinosaurs) was named today by a team of British, American and German researchers. The animal was nicknamed ‘Elvis’ when the fossil was first unearthed in Bavaria, Germany because of the giant pompadour-like bony crest on its skull. 

    Now the animal has been given a formal scientific name of Petrodactyle wellnhoferi. The name translates as ‘Wellnhofer’s stone-finger’ honouring legendary German palaeontologist Peter Wellnhofer who spent his career working on German pterosaurs. Petrodactyle is a member of a group of pterosaurs called the ctenochasmatids that were mostly small filter feeders. Petrodactyle is a very complete skeleton with nearly every bone preserved and in remarkable detail.  

    Many pterosaurs are known with bony crests which they used primarily as sexual signals to other members of the species, but Pterodactyle has by far the largest crest even seen in a ctenochasmatid. Dr David Hone of Queen Mary University of London was the lead author on the study said, “Big though this crest is, we know that these pterosaurs had skin-like extensions attached to it, so in life Petrodactyle would have had an even larger crest”. 

    The details of the specimen are especially clear under UV light which helps show the difference between the bones and the rock in which they are embedded, which under natural light are a very similar colour. René Lauer of the Lauer Foundation, an author on the study said, “The use of UV Induced Fluorescence digital photography provided the ability to discern fine structures small bones and provided additional information regarding the structures of the bony crest which aided in the interpretations and conclusions of this unique new species”. 

    Petrodactyle was unusually large too. It has a wingspan of around 2 meters, but it was still an older ‘teenager’ by pterosaur standards and would have been even larger as a fully mature animal. Even so, it is one of the largest pterosaurs known from the Late Jurassic period. Bruce Lauer of the Lauer Foundation, an author on the study said “The specimen was located in a quarry which is producing scientifically important fossils that provide additional insights into Late Jurassic Pterosaurs.  This research is a great example of the benefits of cooperation between amateur collectors, commercial fossil dealers, our Foundation and research scientists to advance science.” 

    Like other ctenochasmatids, Petrodactyle was at home on the shore of shallow seas but might have ventured into estuaries or to lakes. It’s long jaw with many small teeth would have been good for grabbing at small fish, shrimp and other aquatic prey. However, unlike most other ctenochasmatids, it had an expansion at the back of the skull to attach large jaw muscles and give it a stronger bite than many of its contemporaries. Frederik Spindler of the Dinosaurier Museum in Germany, an author on the study said, “It is amazing to document an increasingly wide range of adaptations.  Pterosaurs were a fundamental part of the Jurassic ecology”. 

    Dr Hone concluded “Peter Wellnhofer is long overdue having a species of German pterosaur named after him to honour his lifelong contribution to the study of these amazing animals”.  

    The Lauer Foundation acquires, curates, and provides access to a collection of scientifically important Palaeontological specimens.  The collection is available to the scientific community for research, publication, exhibition and educational outreach.

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    Queen Mary University of London

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  • Amber abundance in Cretaceous rocks: What’s the reason?

    Amber abundance in Cretaceous rocks: What’s the reason?

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    Newswise — What would a traveler from the future think if one day s/he could analyze the rocks that are currently forming on the planet? Surely, this person would find quite a few plastic fragments and wonder why this material was so abundant in rocks of a certain age on Earth. This is the same question that geologists and palaeontologists have asked themselves after many years of studying another material: amber, the fossilized resin from the Cretaceous that helps us reconstruct what the forests inhabited by dinosaurs were like.

    We know the reason for the abundance of so many plastics in today’s ecosystems, “but we can only estimate the natural causes that would explain the production of large quantities of resin in the Cretaceous,” says Xavier Delclòs, professor at the Faculty of Earth Sciences of the University of Barcelona and first author of an article published in the journal Earth-Science Reviews that addresses this enigmas of modern palaeontology.

    “The stories of plastic and fossil resins are very different, but they have one thing in common: the curiosity involved in observing that some new and relevant phenomenon arose at some point in Earth’s history and was recorded in rocks”, says Delclòs, member of the Department of Earth and Ocean Dynamics and the Biodiversity Research Institute (IRBio) of the UB.

    “Amber, and in particular its abundance, would be of little interest were it not for the fact that it contains in its interior many organisms that inhabited the forests of the past, which have been perfectly preserved as fossils and which today allow us to know the forests of the Cretaceous with a detail that seems unreal sometimes” says Enrique Peñalver, a member of the Geological and Mining Institute of Spain, a national centre of the Spanish National Research Council (CN IGME-CSIC) and also co-author of the study.

    How were the large amber deposits formed?

    The Cretaceous, a period extending from 145.5 to 66 million years ago, represents a time of rapid evolutionary change and diversification of organisms. Today, the dominant conditions that in the Cretaceous allowed the mass formation of abundant resin deposits all over the planet are not present, nor is it known why there was, at the time of the dinosaurs, such an extremely abundant production of resin.

    “For about 54 million years, and for the first time in Earth’s history, there was a mass production of resin by plants, and we still don’t know why”, Delclòs and Peñalver point out. “Production quantities that could have formed fossil resin deposits of what we know today as amber had never been reached. From the Barremian to the Campanian, and thanks to the conditions existing on the planet, certain groups of conifers were able to originate large deposits of fossil resin that open a real window to the ecosystems of the past and today provide very important palaeobiological information. We have called this time span the Cretaceous Resinous Interval (CREI)”.

    The formation of large amber deposits requires the existence of trees with the ability to produce a lot of resin. During the Cretaceous, only gymnosperms —e.g., conifers— which are evolutionarily older than flowering plants, could produce resin. Moreover, the resin had to be trapped in a sedimentary environment without oxygen to preserve it for millions of years. But what environmental or biological factors could have conditioned such resin production in the Cretaceous?

    “Our study shows that, during the Cretaceous, coniferous forests were widely distributed across the planet. These amber deposits formed during the CREI shared these characteristics: high resin production exclusively by conifers; the presence of fusain, a material derived from plant material burnt by forest fires; fossils preserved in amber that correspond to similar fauna and flora among different deposits; and resin accumulation in transitional sedimentary environments under subtropical and temperate paleoclimates that coincide with the onset of sea-level rise stages.

    The study also indicates that the mass production of resin was not continuous during the CREI nor was it equal everywhere: there were times of higher and lower production. In the study, carried out by a large multidisciplinary group of experts, the participation of Ricardo Pérez de la Fuente, from the Oxford University Museum (United Kingdom), is particularly noteworthy.

    An open window to the vanished world of the Cretaceous

    Pieces of amber recovered by palaeontologists in different sites around the world provide new insights into the Cretaceous. This period saw the emergence of large terrestrial ecosystems dominated by angiosperms — flowering plants — and many of the evolutionary lines of present-day organisms. The distribution of continents and ocean currents was altered, the climate was warmer and more humid than today’s, and sea levels rose more than 200 meters above today’s coastlines.

    “In the atmosphere there were high levels of carbon dioxide (CO2) due to intense volcanism, but also of oxygen (O2) due to the great extension of forests to latitudes now covered by ice, a feature that also enhances large-scale fires”, Delclòs and Peñalver note.

    This is the global landscape and environment that dominated the Earth during much of the Cretaceous. The environmental factors conditioned the life and evolution of the organisms that existed on the planet, especially the terrestrial ones, from the smallest to the great dinosaurs, and the relationships between the different species.

    In this scenario, the CREI emerges as a global phenomenon, with amber outcrops distributed everywhere during the Cretaceous, and concentrated especially in Laurasia and the northern margin of Gondwana. Environmental factors may have affected on a global scale, while biological factors — interaction between plants and arthropods, etc. — may have acted on a regional scale.

    “CREI represents a great window to a vanished world, at the beginnings of modern ecosystems dominated by flowering plants, where dinosaurs lived, and where the lineages of the first birds and mammals evolved. Studying this period allows us to obtain many data of maximum scientific interest on phylogenetic relationships, extinct organisms, the beginning of behaviours that we can recognize today in many groups, intra- and interspecific relationships of extinct organisms (parasitism, pollination, parental care, swarming, forestry, reproduction, etc.) of the inhabitants of a terrestrial environment —the forest— that are not usually fossilized”, the experts conclude.

     

    https://www.sciencedirect.com/science/article/abs/pii/S0012825223001757

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    Universidad De Barcelona

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  • Earliest Levantine wind instruments found

    Earliest Levantine wind instruments found

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    Newswise — Although the prehistoric site of Eynan-Mallaha in northern Israel has been thoroughly examined since 1955, it still holds some surprises for scientists. Seven prehistoric wind instruments known as flutes, recently identified by a Franco-Israeli team1, are the subject of an article published on 9 June in Nature Scientific Reports. The discovery of these 12,000 -year-old aerophones is extremely rare – in fact, they are the first to be discovered in the Near East. The “flutes”, made from the bones of a small waterfowl, produce a sound similar to certain birds of prey (Eurasian sparrowhawk and common kestrel) when air is blown into them. The choice of bones used to make these instruments was no accident – larger birds, with bigger bones that produce deeper sounds, have also been found at the site. The Natufians, the Near Eastern civilisation that occupied this village between 13,000 and 9,700 BC, deliberately selected smaller bones in order to obtain the high-pitched sound needed to imitate these particular raptors. The instruments may have been used for hunting, music or to communicate with the birds themselves. Indeed, it is clear that the Natufians attributed birds with a special symbolic value, as attested by the many ornaments made of talons found at Eynan-Mallaha. The village, located on the shores of Lake Hula, was home to this civilisation throughout its 3,000 years of existence. It is therefore of vital importance in revealing the practices and habits of a culture at the crossroads between mobile and sedentary lifestyles, and the transition from a predatory economy to agriculture. This work2 was supported by the Fyssen Fondation and the ministère des Affaires étrangères.

     

    Notes

    1. The team is co-directed by Laurent Davin (post-doctoral researcher at the Fyssen Fondation) and José-Miguel Tejero (University of Vienna, University of Barcelona) and includes scientists from the Centre de recherche français à Jérusalem (CNRS/Aix-Marseille Université/ministère de la Culture), the laboratoire Technologie et ethnologie des mondes préhistoriques (CNRS/Université Panthéon-Sorbonne/Université Paris Nanterre), The Hebrew University of Jerusalem (Institute of Archaeology), Israel Antiquities Authority, Virginia Commonwealth University (Department of Forensic Science), École Nationale Vétérinaire (Laboratoire d’Anatomie comparée, Nantes), the laboratoire Archéologies et sciences de l’Antiquité (CNRS/ministère de la Culture/Université Panthéon-Sorbonne/Université Paris Nanterre) and the l’Institut d’ethnologie méditerranéenne, européenne et comparative (CNRS/Université Aix-Marseille).
    2. Excavation of the Eynan-Mallaha site is still ongoing, under the direction of CNRS researcher Fanny Bocquentin and Israel Antiquities Authority researcher Lior Weisbrod.

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    CNRS (Centre National de Recherche Scientifique / National Center of Scientific Research)

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  • Ancient herbivore’s diet weakened teeth leading to eventual starvation, study suggests

    Ancient herbivore’s diet weakened teeth leading to eventual starvation, study suggests

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    BYLINE: Laura Thomas

    Newswise — A team of researchers from the University of Bristol have shed light on the life of the ancient reptile Rhynchosaur, which walked the earth between 250-225 million years ago, before being replaced by the dinosaurs.

    Rhynchosaurs are a little-understood group of roughly sheep-sized ancient reptiles that thrived during the Triassic Period, a time of generally warm climates and tough vegetation.  

    In the new study, the researchers studied specimens found in Devon and used CT scanning to see how the teeth wore down as they fed, and how new teeth were added at the backs of the tooth rows as the animals grew in size.

    The findings, published today in Palaeontology, show that these early herbivores likely eventually starved to death in old age, the vegetation taking its toll on their teeth.

    “I first studied the rhynchosaurs years ago,” said team-leader Professor Mike Benton from Bristol’s School of Earth Sciences, “and I was amazed to find that in many cases they dominated their ecosystems. If you found one fossil, you found hundreds. They were the sheep or antelopes of their day, and yet they had specialized dental systems that were apparently adapted for dealing with masses of tough plant food.”

    Dr Rob Coram, who discovered the Devon fossils, said: “The fossils are rare, but occasionally individuals were entombed during river floods. This has made it possible to put together a series of jaw bones of rhynchosaurs that ranged in age from quite young, maybe even babies, through adults, and including one particularly old animal, a Triassic old-timer whose teeth had worn right down and probably struggled to get enough nutrition each day.”

    “Comparing the sequence of fossils through their lifetime, we could see that as the animals aged, the area of the jaws under wear at any time moved backwards relative to the front of the skull, bringing new teeth and new bone into wear,” said Thitiwoot Sethapanichsakul who studied the jaws as part of his MSc in Palaeobiology. “They were clearly eating really tough food such as ferns, that wore the teeth down to the bone of the jaw, meaning that they were basically chopping their meals by a mix of teeth and bone.”

    “Eventually, though, after a certain age – we’re not sure quite how many years – their growth slowed down and the area of wear was fixed and just got deeper and deeper,” added Dr Coram. “It’s like elephants today – they have a fixed number of teeth that come into use from the back, and after the age of seventy or so they’re on their last tooth, and then that’s that.

    “We don’t think the rhynchosaurs lived that long, but their plant food was so testing that their jaws simply wore out and presumably they eventually starved to death.”

    The rhynchosaurs were an important part of the ecosystems on land during the Triassic, when life was recovering from the world’s greatest mass extinction, at the end of the preceding Permian Period. These animals were part of this recovery and setting the scene for new types of ecologies when first dinosaurs, and later mammals became dominant, as the modern world was being slowly constructed.

    By comparing examples of earlier rhynchosaurs, such as those from Devon, with later-occurring examples from Scotland and Argentina, the team were also able to show how their dentitions evolved through time, and how their unique teeth enabled them to diversify twice, in the Middle and then in the Late Triassic. But in the end, climate change, and especially changes of available plants, seem to have enabled the dinosaurs to take over as the rhynchosaurs died out.

    The paper

    ‘Unique dentition of rhynchosaurs and their two-phase success as herbivores in the Triassic’ By Sethapanichsakul, T., Coram, R.A. and Benton, M.J. Palaeontology. Doi: 10.1111/pala.12654

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    University of Bristol

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  • Fossil Discovery Revises Cycad Plant History

    Fossil Discovery Revises Cycad Plant History

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    Newswise — LAWRENCE — Cycads, a group of gymnosperms which can resemble miniature palm trees (like the popular sago palm houseplant) were long thought to be “living fossils,” a group that had evolved minimally since the time of the dinosaurs. Now, a well-preserved 80-million-year-old pollen cone discovered in California has rewritten scientific understanding of the plants.

    The findings are detailed in a paper by two University of Kansas paleobotanists just published in the journal New Phytologist.

    “Cycads aren’t well-known but make up a significant part of plant diversity, accounting for around 25% of all gymnosperms,” said lead author Andres Elgorriaga, postdoctoral researcher with the KU Department of Ecology & Evolutionary Biology and KU Biodiversity Institute and Natural History Museum. “Cycads are plants that have thick stems and short stature, with thick, palm-like leaves on top. They produce cones like pine cones and are related to other seed-bearing plants that also don’t produce flowers, like Ginkgo and the monkey puzzle tree. But they’re also highly endangered, with the highest level of endangerment among all plant groups. Trafficking of cycads also is a significant issue.”

    Despite their importance, a lack of fossil evidence and confusion over the years about how to classify some fossil specimens has led to a murky scientific grasp of the plants’ evolutionary history. One prominent idea was that cycads today are nearly identical to their prehistoric ancestors.  

    “The prevailing school of thought is that cycads did not change much in deep time,” said co-author Brian Atkinson, assistant professor of ecology & evolutionary biology and curator of paleobotany at the KU Biodiversity Institute and Natural History Museum. “But the fossil record of cycads is poorly understood, and many things that have been called cycads have turned out not to be cycads at all. Here, we have a three-dimensionally preserved cone clearly assignable to cycads because it has internal anatomy and pollen grains typical of this group. However, the external morphology of this pollen cone is different from living cycads today. This finding suggests cycads aren’t really ‘living fossils’ and they probably have a more dynamic evolutionary history than previously thought.”

    According to the KU researchers, their analysis of an 80-million-year-old permineralized pollen cone found in the Campanian Holz Shale formation located in Silverado Canyon, California, tells a more accurate cycad natural history — one where the plants diversified during the Cretaceous.

    “With this type of discovery, we realize during this time there were cycads that were really different than the ones today in their size, in their number of pollen sacs, in a lot of things,” Elgorriaga said. “Maybe we haven’t found that many cycad fossils as well — or maybe we’re finding them but we’re just not recognizing them because they were so different from how they are today. They aren’t ‘living fossils.’ They were different in the past.”

    To perform their analysis, Elgorriaga and Atkinson studied the specimen’s cone’s architecture, anatomical details and vasculature organization using serial sectioning, scanning electron microscopy and 3D reconstruction. They also performed a series of evolutionary analyses to place the fossil within the cycad family tree.

    Relying partly on the shapes of the cone’s scales, pollen and pollen sacs, they assigned the ancient plant to Skyttegaardia, a recently described genus based on isolated cone scales found in Denmark and dated to the Early Cretaceous (about 125 million years ago). Further, they erase some initial doubt about the new genus’ placement in the cycad group.

    “The 3D reconstruction was striking because it only had two pollen sacs per cone scale, and the form of this cone scale reminded us of a fossil described from Scandinavia called Skyttegaardia,” Atkinson said. “There were many similarities, but the original in Scandinavia was only described in 2021 based on isolated cone scales. They cautiously explored the idea that the fossil belonged to cycad but were uncomfortable with firmly concluding this primarily because it only had two pollen sacs per cone scale — while cycads today have 20 to 700. Most cycad pollen cones are quite large, while this fossil was only half a centimeter in length.”

    With the additional information from the new fossil plant, the KU researchers were “quite confident” in their phylogenetic analysis showing Skyttegaardia’s positive relationship with cycads.

    The investigators said their description of the primordial plant shows how paleobotany can tell us more about how nature works through deep time.

    “This shows us that the information we collect from the fossil record greatly impacts our understanding of evolutionary patterns,” Atkinson said. “Time, just like fossils, can reveal insights that aren’t apparent from studying only living plants or organisms. This case study is an excellent example of how fossils can contribute to our understanding of evolution over extended periods.”

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    University of Kansas

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  • “Golden” Fossils Show Exceptional Preservation Origins

    “Golden” Fossils Show Exceptional Preservation Origins

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    Newswise — All that glitters is not gold, or even fool’s gold in the case of fossils.

    A recent study by scientists at The University of Texas at Austin and collaborators found that many of the fossils from Germany’s Posidonia shale do not get their gleam from pyrite, commonly known as fool’s gold, which was long thought to be the source of the shine. Instead, the golden hue is from a mix of minerals that hints at the conditions in which the fossils formed.

    The discovery is important for understanding how the fossils — which are among the world’s best-preserved specimens of sea life from the Early Jurassic — came to form in the first place, and the role that oxygen in the environment had in their formation.

    “When you go to the quarries, golden ammonites peek out from black shale slabs,” said study co-author Rowan Martindale, an associate professor at the UT Jackson School of Geosciences. “But surprisingly, we struggled to find pyrite in the fossils. Even the fossils that looked golden, are preserved as phosphate minerals with yellow calcite. This dramatically changes our view of this famous fossil deposit.”

    The research was published in Earth Science Reviews. Drew Muscente, a former assistant professor at Cornell College and former Jackson School postdoctoral researcher, led the study.

    The fossils of the Posidonia Shale date back to 183 million years ago, and include rare soft-bodied specimens such as ichthyosaur embryos, squids with ink-sacs, and lobsters. To learn more about the fossilization conditions that led to such exquisite preservation, the researchers put dozens of samples under scanning electron microscopes to study their chemical composition.

    “I couldn’t wait to get them in my microscope and help tell their preservational story,” said co-author Jim Schiffbauer, an associate professor at the University of Missouri Department of Geological Sciences, who handled some of the larger samples.

    The researchers found that in every instance, the fossils were primarily made up of phosphate minerals even though the surrounding black shale rock was dotted with microscopic clusters of pyrite crystals, called framboids.

    “I spent days looking for the framboids on the fossil,” said co-author Sinjini Sinha, a doctoral student at the Jackson School. “For some of the specimens, I counted 800 framboids on the matrix while there was maybe three or four on the fossils.”

    The fact that pyrite and phosphate are found in different places on the specimens is important because it reveals key details about the fossilization environment. Pyrite forms in anoxic (without oxygen) environments, but phosphate minerals need oxygen. The research suggests that although an anoxic seafloor sets the stage for fossilization — keeping decay and predators at bay — it took a pulse of oxygen to drive the chemical reactions needed for fossilization.

    These findings complement earlier research carried out by the team on the geochemical conditions of sites known for their caches of exceptionally preserved fossils, called konservat-lagerstätten. However, the results of these studies contradict long-standing theories about the conditions needed for exceptional fossil preservation in the Posidonia.

    “It’s been thought for a long time that the anoxia causes the exceptional preservation, but it doesn’t directly help,” said Sinha. “It helps with making the environment conducive to faster fossilization, which leads to the preservation, but it’s oxygenation that’s enhancing preservation.”

    It turns out, the oxygenation — and the phosphate and accompanying minerals — also enhanced the fossil’s shine.

    The research was funded by Cornell College and the National Science Foundation. The Posidonia fossil specimens used in this study are now part of the collections at the Jackson School’s Non-Vertebrate Paleontology Laboratory.

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    University of Texas at Austin (UT Austin)

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  • Feathered Dinosaurs & Feather-Feeding Beetles: A Long-Term Bond

    Feathered Dinosaurs & Feather-Feeding Beetles: A Long-Term Bond

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    Newswise — New fossils in amber have revealed that beetles fed on the feathers of dinosaurs about 105 million years ago, showing a symbiotic relationship of one-sided or mutual benefit, according to an article published in Proceedings of the National Academy of Sciences of the United States of America today*. 

    The main amber fragments studied, from the Spanish locality of San Just (Teruel), contain larval moults of small beetle larvae tightly surrounded by portions of downy feathers. The feathers belonged to an unknown theropod dinosaur, either avian (a term referring to “birds” in wide sense) or non-avian, as both types of theropods lived during the Early Cretaceous and shared often indistinguishable feather types. However, the studied feathers did not belong to modern birds since the group appeared about 30 million years later in the fossil record, during the Late Cretaceous. 

    When looking at modern ecosystems, we see how ticks infest cattle, frogs capture insects with acrobatic tongues, or some barnacles grow on the skin of whales. These are just a few of the diverse and complex ecological relationships between vertebrates and arthropods, which have coexisted for more than 500 million years. The way that these two groups have interacted throughout deep time is thought to have critically shaped their evolutionary history, leading to coevolution. Nevertheless, evidence of arthropod-vertebrate relationships is extremely rare in the fossil record. 

    The larval moults preserved in the amber were identified as related to modern skin beetles, or dermestids. Dermestid beetles are infamous pests of stored products or dried museum collections, feeding on organic materials that are hard for other organisms to decay such as natural fibres. However, dermestids also play a key role in the recycling of organic matter in the natural environment, commonly inhabiting nests of birds and mammals, where feathers, hair, or skin accumulate. 

    “In our samples, some of the feather portions and other remains – including minute fossil faeces, or coprolites – are in intimate contact with the moults attributed to dermestid beetles and show occasional damage and/or signs of decay. This is hard evidence that the fossil beetles almost certainly fed on the feathers and that these were detached from its host,” explains Dr Enrique Peñalver, from the Geological and Mining Institute of Spain of the Spanish National Research Council (CN IGME-CSIC) and lead author of the study. 

    “The beetle larvae lived −feeding, defecating, moulting− in accumulated feathers on or close to a resin-producing tree, probably in a nest setting. A flow of resin serendipitously captured that association and preserved it for millions of years.” 

    “Three additional amber pieces each containing an isolated beetle moult of a different maturity stage but assigned to the same species were also studied, allowing a better understanding of these minute insects than what is usually possible in palaeontology,” says Dr David Peris, from the Botanical Institute of Barcelona (CSIC-Barcelona City Council) and co-author of the study. The most impressive, complete specimen was found in the amber deposit of Rábago/El Soplao in the northern Spain, roughly of the same age as San Just. 

    “It is unclear whether the feathered theropod host also benefitted from the beetle larvae feeding on its detached feathers in this plausible nest setting,” says Dr Ricardo Pérez-de la Fuente, from Oxford University Museum of Natural History and co-lead author of the study. “However, the theropod was most likely unharmed by the activity of the larvae since our data show these did not feed on living plumage and lacked defensive structures which among modern dermestids can irritate the skin of nest hosts, even killing them.” 

    ** 

    Notes 

    • The international and multidisciplinary team comprised researchers from the Geological and Mining Institute of Spain of the Spanish National Research Council (CN IGME-CSIC), the Botanical Institute of Barcelona (IBB-CSIC), the University of Barcelona and the Institute for Research on Biodiversity (IRBio), the Complutense University of Madrid, the ‘Parque de las Ciencias’ of Andalusia, the Autonomous University of Madrid, and the Royal Academy of Exact, Physical and Natural Sciences (Spain); the American Museum of Natural History and the Natural History Museum of Los Angeles County (United States of America); the Senckenberg Research Institute (Germany); and Oxford University Museum of Natural History (United Kingdom). 

    • Funding bodies: the project CRE, funded by the Spanish AEI/FEDER, UE Grant CGL2017-84419, the project PGC2018-094034-B-C22 (MCIU/AEI/FEDER, UE), the project CGL2014-52163, funded by the Spanish Ministry of Economy, Industry, and Competitiveness, the Secretary of Universities and Research of the Government of Catalonia and European Social Fund (2021FI_B2 00003), and the Consejería de Industria, Turismo, Innovación, Transporte y Comercio of the Gobierno de Cantabria through the public enterprise EL SOPLAO S.L. 

     

     

    About Oxford University Museum of Natural History   

    Founded in 1860 as the centre for scientific study at the University of Oxford, the Museum of Natural History now holds the University’s internationally significant collections of entomological, geological and zoological specimens. Housed in a stunning Pre-Raphaelite-inspired example of neo-Gothic architecture, the Museum’s growing collections underpin a broad programme of natural environment research, teaching and public engagement.  

    www.oumnh.ox.ac.uk  

    www.morethanadodo.com  

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    University of Oxford

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  • Africa: Open Habitats 10M Yrs Older Than Thought – New Studies

    Africa: Open Habitats 10M Yrs Older Than Thought – New Studies

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    Newswise — The story of human evolution has long been a tale of a forested Africa that gradually became drier, giving rise to open grasslands and causing our forest-loving ape ancestors to abandon the trees and become bipedal. Even though ecological and fossil evidence suggested this narrative was too simplistic, the theory remains prominent in many evolutionary scenarios. 

    Two new studies recently published in Science led by researchers at the University of Minnesota Twin Cities put this idea to rest. The findings outline paleoecological reconstructions of early ape fossil sites in eastern Africa dated to the Early Miocene — between 23 and 16 million years ago — showing early apes lived in a wide variety of habitats, including open habitats like scrublands and wooded grasslands that existed 10 million years earlier than previously known.

    Research findings include:

    • Some of these habitats included substantial C4 plant biomass, grasses that today characterize tropical savannas, but were thought previously to have become dominant only 10 million years ago. 
    • Modern ape anatomy may have evolved in open woodlands among leaf-eating apes rather than in forest-dwelling fruit-eating apes.
    • The combination of open habitats with significant C4 biomass in the Early Miocene suggests that traditional scenarios regarding the evolution of animal and plant communities in Africa, including the origin of hominins, need to be reconsidered.

    Researchers across nine fossil site complexes — which included 30 experts from African, North American and European institutions — conducted paleontological and geological fieldwork, collecting thousands of fossil plant and animal remains and sampling fossil deposits for multiple lines of evidence to reconstruct the ancient habitats.

    “None of us could have reached these conclusions working in isolation at our individual fossil sites,” said Kieran McNulty, a professor of Anthropology in the College of Liberal Arts, lead author and organizer of the decade-long Research on East African Catarrhine and Hominoid Evolution (REACHE) project. “Working in the fossil record is challenging. We discover hints about past life and need to assemble and interpret them across space and time. It’s like a 4D puzzle, where each team member can only see some of the pieces.”

    “You go into a project like this not knowing for sure what you will find out, which is exciting. In this case, we realized we were looking at a picture of Early Miocene communities in eastern Africa that is quite different than what we had expected,” said David Fox, a professor in the Earth and Environmental Sciences Department in the College of Science and Engineering. “There was no single ‘ah ha moment’ but over years of field seasons and the steady accumulation of new fossils and new data, we realized that the environments of the earliest apes varied significantly from the traditional picture of forested habitats.”

    “The findings have transformed what we thought we knew about early apes, and the origin for where, when and why they navigate through the trees and on the ground in multiple different ways,” said Robin Bernstein, program director for biological anthropology at the National Science Foundation. “For the first time, by combining diverse lines of evidence, this collaborative research team tied specific aspects of early ape anatomy to nuanced environmental changes in their habitat in eastern Africa, now revealed as more open and less forested than previously thought. The effort outlines a new framework for future studies regarding ape evolutionary origins.”

    Continued research at these fossil sites will enhance our understanding of these habitats, especially of finer-grained changes in space and time. Likewise, similar collaborations focused on earlier and later time periods are needed to fully understand the interactions between fossil species and their environments.

    “This level of cooperation among different teams is unique in paleoanthropology,” said McNulty. “These two studies highlight the importance of extending collaboration and dialog beyond our immediate research partners.”

    The research was funded by the National Science Foundation, Leakey Foundation, McKnight Land-Grant Fellowship, and Leverhulme Trust Fellowship.

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    University of Minnesota

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  • Meet the titanosaur: Dinosaur giant goes on display in Europe for the first time | CNN

    Meet the titanosaur: Dinosaur giant goes on display in Europe for the first time | CNN

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    London
    CNN
     — 

    In the venerated halls of London’s Natural History Museum, one of the largest animals ever to walk the Earth is about to make its debut.

    Patagotitan mayorum, a dinosaur giant belonging to a group known as titanosaurs, is visiting Europe for the first time since its discovery in Argentina in 2010. Over five meters (16 feet) tall and weighing over two and a half metric tons, its skeleton will give visitors an idea of what this gentle giant, which could have weighed as much as 57 metric tons and stretched over 120 feet, would have looked like when it lived on Earth around 100 million years ago.

    A team of technicians is putting the finishing touches to the star exhibit, which arrived in the UK in January and has been reconstructed in a room with a specially reinforced floor, said Sinead Marron, exhibition and interpretation manager at the museum.

    Displayed alongside the skeleton, which is a cast, are real fossils, including a 2.4-meter-long (8 feet) femur that weighs around half a metric ton.

    “The idea of the exhibition has been in the works for a few years now,” said Marron, explaining that it was disrupted by the Covid pandemic. “We’re so excited to finally introduce Patagotitan to the UK.”

    When Patagotitan mayorum was first excavated, it rocked the world of palaeontology. More than nine times heavier than the African elephant and longer than a blue whale, the giant herbivore may have been the largest terrestrial animal of all time.

    The first evidence of the Patagotitan emerged in 2010 with the discovery of a single bone, before a more extensive dig in 2013 yielded more than 180 bones from seven partial skeletons. Evidence suggests the dinosaurs were buried in floods.

    A graphic illustrating the titanosaur's size relative to a diploducus and an African elephant.

    The fossils were 3-D scanned and used by the Museo Paleontológico Egidio Feruglio (MEF) in Argentina as the basis of a whole skeleton cast comprising nearly 300 bones. The cast comprises a shell of fiberglass and polyester resin, filled with expanding foam, displayed on a steel framework.

    “The replica is a composite – it incorporates bones from at least six different individuals found at the site,” explained Marron. “For the bones that weren’t found, the specialist team at MEF have filled in the gaps using what we know from closely related dinosaurs.”

    Replicas of Patagotitan mayorum reside in the American Museum of Natural History in New York and the Field Museum of Natural History in Chicago, but the dinosaur hadn’t been exhibited in Europe before the Natural History Museum took loan of the MEF’s cast.

    A specialist department of freight company IAG Cargo was tasked with transporting the dinosaur from Argentina.

    CEO David Shepherd told CNN the department has transported items including terracotta soldiers, Egyptian mummies and Assyrian treasures to the UK, which, due to their value and delicate nature, means staff and customers go through strict screening requirements to ensure items’ safety. “Cargo is stored in state-of-the-art vaults that are constantly monitored using CCTV and active human surveillance,” he said.

    The cast and fossils were stored in more than 40 specially designed crates. These were placed in the belly hold of two British Airways Boeing 787 Dreamliners and flown 7,000 miles from Ezeiza Airport, Buenos Aires, to London Heathrow, before they were taken to a special facility ahead of transportation to the museum.

    Unboxing the 2.4 meter (8 foot) long femur fossil, which weighs around half a ton.

    “The fossils are significantly heavier than the replicas which makes storing, moving and displaying them more complicated than for the replicas,” said Marron. “In addition, the original fossils are of immense value to scientific research.”

    “For this move, every single bone required a temporary export permit for paleontological heritage,” Shepherd explained. “This is very similar to a passport and includes details such as the name and code of the collection, its weight, size and a photograph, as well as insurance and a visa-like document, giving it permission to be out of the country for a specified time.”

    Clearing customs and security checks took four days, he added.

    Workers reconstruct the cast inside the Natural History Museum.

    Assembly inside the museum’s Waterhouse Gallery has happened away from the public eye. “There was a lot of measurement-checking to ensure that we could actually get the specimens into our Victorian, grade II listed building,” said Marron.

    The official unveiling on Friday March 31 is timed to coincide with the start of UK school holidays, and huge crowds are expected.

    “We hope visitors will experience a sense of awe at the sheer scale of the titanosaur. It’s an incredible experience to stand underneath it, to be dwarfed by this immense creature,” said Marron.

    But with the new addition, has the museum considered Dippy’s feelings? The beloved diplodocus skeleton, until 2015 a stalwart of the museum and currently on tour in the UK, is not in London to defend its patch.

    The two dinosaurs won’t be having a meeting of minds, however “we’re pretty sure Dippy is excited that a big cousin has come to visit,” Marron said.

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  • How the “marsupial sabertooth” thylacosmilus saw its world

    How the “marsupial sabertooth” thylacosmilus saw its world

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    Newswise — A new study investigates how an extinct, carnivorous marsupial relative with canines so large they extended across the top of its skull could hunt effectively despite having wide-set eyes, like a cow or a horse. The skulls of carnivores typically have forward-facing eye sockets, or orbits, which helps enable stereoscopic (3D) vision, a useful adaptation for judging the position of prey before pouncing. Scientists from the American Museum of Natural History and the Instituto Argentino de Nivología, Glaciología, y Ciencias Ambientales in Mendoza, Argentina, studied whether the “marsupial sabertooth” Thylacosmilus atrox could see in 3D at all. Their results are published today in the journal Communications Biology.

    Popularly known as the “marsupial (or metatherian) sabertooth” because its extraordinarily large upper canines recall those of the more famous placental sabertooth that evolved in North America, Thylacosmilus lived in South America until its extinction about 3 million years ago. It was a member of Sparassodonta, a group of highly carnivorous mammals related to living marsupials. Although sparassodont species differed considerably in size—Thylacosmilus may have weighed as much as 100 kilograms (220 pounds)—the great majority resembled placental carnivores like cats and dogs in having forward-facing eyes and, presumably, full 3D vision. By contrast, the orbits of Thylacosmilus, a supposed hypercarnivore—an animal with a diet estimated to consist of at least 70 percent meat—were positioned like those of an ungulate, with orbits that face mostly laterally. In this situation, the visual fields do not overlap sufficiently for the brain to integrate them in 3D. Why would a hypercarnivore evolve such a peculiar adaptation? A team of researchers from Argentina and the United States set out to look for an explanation.

    “You can’t understand cranial organization in Thylacosmilus without first confronting those enormous canines,” said lead author Charlène Gaillard, a Ph.D. student in the Instituto Argentino de Nivología, Glaciología, y Ciencias Ambientales (INAGLIA). “They weren’t just large; they were ever-growing, to such an extent that the roots of the canines continued over the tops of their skulls. This had consequences, one of which was that no room was available for the orbits in the usual carnivore position on the front of the face.”

    Gaillard used CT scanning and 3D virtual reconstructions to assess orbital organization in a number of fossil and modern mammals. She was able to determine how the visual system of Thylacosmilus would have compared to those in other carnivores or other mammals in general. Although low orbital convergence occurs in some modern carnivores, Thylacosmilus was extreme in this regard: it had an orbital convergence value as low as 35 degrees, compared to that of a typical predator, like a cat, at around 65 degrees.

    However, good stereoscopic vision also relies on the degree of frontation, which is a measure of how the eyeballs are situated within the orbits. “Thylacosmilus was able to compensate for having its eyes on the side of its head by sticking its orbits out somewhat and orienting them almost vertically, to increase visual field overlap as much as possible,” said co-author Analia M. Forasiepi, also in INAGLIA and a researcher in CONICET, the Argentinian science and research agency. “Even though its orbits were not favorably positioned for 3D vision, it could achieve about 70 percent of visual field overlap—evidently, enough to make it a successful active predator.”

    “Compensation appears to be the key to understanding how the skull of Thylacosmilus was put together,” said study co-author Ross D. E. MacPhee, a senior curator at the American Museum of Natural History. “In effect, the growth pattern of the canines during early cranial development would have displaced the orbits away from the front of the face, producing the result we see in adult skulls. The odd orientation of the orbits in Thylacosmilus actually represents a morphological compromise between the primary function of the cranium, which is to hold and protect the brain and sense organs, and a collateral function unique to this species, which was to provide enough room for the development of the enormous canines.”

    Lateral displacement of the orbits was not the only cranial modification that Thylacosmilus developed to accommodate its canines while retaining other functions. Placing the eyes on the side of the skull brings them close to the temporal chewing muscles, which might result in deformation during eating. To control for this, some mammals, including primates, have developed a bony structure that closes off the eye sockets from the side. Thylacosmilus did the same thing—another example of convergence among unrelated species.

    This leaves a final question: What purpose would have been served by developing huge, ever-growing teeth that required re-engineering of the whole skull?

    “It might have made predation easier in some unknown way,” said Gaillard, “But, if so, why didn’t any other sparassodont—or for that matter, any other mammalian carnivore—develop the same adaptation convergently? The canines of Thylacosmilus did not wear down, like the incisors of rodents. Instead, they just seem to have continued growing at the root, eventually extending almost to the rear of the skull.”

    Forasiepi underlined this point, saying, “To look for clear-cut adaptive explanations in evolutionary biology is fun but largely futile. One thing is clear: Thylacosmilus was not a freak of nature, but in its time and place it managed, apparently quite admirably, to survive as an ambush predator. We may view it as an anomaly because it doesn’t fit within our preconceived categories of what a proper mammalian carnivore should look like, but evolution makes its own rules.”

     

    ABOUT THE AMERICAN MUSEUM OF NATURAL HISTORY (AMNH)

    The American Museum of Natural History, founded in 1869, is one of the world’s preeminent scientific, educational, and cultural institutions. The Museum encompasses more than 40 permanent exhibition halls and galleries for temporary exhibitions, the Rose Center for Earth and Space and the Hayden Planetarium, and the Richard Gilder Center for Science, Education, and Innovation, which opens in 2023. The Museum’s scientists draw on a world-class permanent collection of more than 34 million specimens and artifacts, some of which are billions of years old, and on one of the largest natural history libraries in the world. Through its Richard Gilder Graduate School, the Museum grants the Ph.D. degree in Comparative Biology and the Master of Arts in Teaching (MAT) degree, the only such freestanding, degree-granting programs at any museum in the United States. The Museum’s website, digital videos, and apps for mobile devices bring its collections, exhibitions, and educational programs to millions around the world. Visit amnh.org for more information.

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    American Museum of Natural History

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  • Discovery of oldest known fossil gnat shows how insects adapted to a postapocalyptic world

    Discovery of oldest known fossil gnat shows how insects adapted to a postapocalyptic world

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    • A new fossil discovery dating from ‘just’ a few million years after the greatest mass extinction provides the earliest evidence of the insect group that includes mosquitoes and flies 

    • The fossil, found in Mallorca, Spain, is an immature insect related to modern window- or wood-gnats 

    • The excellent preservation of the fossil has allowed detailed studies, including determining its breathing system 

    Newswise — Near the small harbour of Estellencs at the northeast of Mallorca (Balearic Islands, Spain), a pebbly beach can be found at the base of an impressive scarp that threatens rockfall. Remains of plants, crustaceans, insects, and fish have been discovered in the grey-blue rock layers formed from sediments deposited 247 million years ago. Fossils in these rocks are of great interest since they offer a window into the time where the planet was recovering from the greatest mass extinction. 

    A few years ago, Mallorcan researcher Josep Juárez made a surprising find during a palaeontological survey in the area – a complete insect larva that had left a slight imprint of organic remains on the two sides that were left exposed when the rock split in half. The detailed study of the fossil had to wait, but eventual examination with a powerful microscope revealed that it was a unique discovery. The larva, very well preserved, belongs to a group of insects that we all know, the dipterans — that is, true flies, mosquitoes, midges, and gnats. Although thousands of fossil dipterans have been found across the globe, both in thinly layered rocks and in amber, this specimen, 247 million years old (early Middle Triassic) –older than the earliest dinosaurs– is the oldest dipteran ever found. This record was previously held by fossils found in France, about one or two million years younger than those from Estellencs. 

    Enrique Peñalver, from the Spanish National Research Council (CSIC) at the Spanish Geological Survey (CN-IGME), and first author of the recently published study on the new fossil, says: “While I was inspecting it under the microscope, I put a drop of alcohol on it to increase the contrast of the structures, and I was able to witness in awe how the fossil had preserved both the external and internal structures of the head, some parts of the digestive system, and, most importantly, the external openings to its respiratory system, or spiracles.”

    Rafel Matamales-Andreu, palaeontologist from the Balearic Museum of Natural Sciences (FJBS-MBCN) and another author of the study, has devoted several years to unravel the environment of this region during the Triassic period, and the changes it underwent for millions of years. “If we were able to visit the region at the beginning of the Triassic, we would see large rivers and floodplains under a climate similar to that found in tropical Africa today, alternating dry and rainy seasons,” he points out. 

    This larva fed on organic matter from the soil ‘just’ a few million years in the aftermath of likely the most dramatic mass extinction in the history of life on Earth, which erased more than 80 per cent of the species and led to the end of the Palaeozoic Era. “We have been able to look at some of the adaptations by the first dipterans to the postapocalyptic environment at the beginning of the Triassic, for instance, a breathing system that is still found in different groups of insects today”, remarks Ricardo Pérez-de la Fuente, from Oxford University Museum of Natural History and also an author of the study.  

    The authors have described a new genus and species related to modern window- or wood-gnats named Protoanisolarva juarezi, or “Juárez’s ancestral anisopodoid larva”, honouring its discoverer. This precious fossil is currently being conditioned at the Catalan Institute of Palaeontology Miquel Crusafont for its permanent custody in Mallorca. 

    ** 

    Notes 

    • The open access paper was published in the journal Papers in Palaeontology and can be found at: https://onlinelibrary.wiley.com/doi/full/10.1002/spp2.1472 

    • The international team comprised researchers from the Spanish Geological Survey (CN-IGME) and the Spanish National Research Council (CSIC), Spain, the Balearic Museum of Natural Sciences (FJBS-MBCN), Mallorca, Spain, the National Museum of Natural History of France and the Sorbonne University in Paris, France, and Oxford University Museum of Natural History, United Kingdom. 

    • Funding bodies: Department of Culture, Heritage and Linguistic Policies from the Insular Council of Mallorca, with the project ‘Mallorca before the dinosaurs: study of the continental ecosystems from the Permian and the Triassic, with special emphasis on the vertebrate remains´ (Ref. 15 – 619/2020); Spanish Geological Survey (CN-IGME, Spain), CERCA program (Government of Catalonia, Spain), predoctoral grant FPU17/01922 from the Ministry of Science, Innovation and Universities, Government of Spain.

     

    About Oxford University Museum of Natural History   

    Founded in 1860 as the centre for scientific study at the University of Oxford, the Museum of Natural History now holds the University’s internationally significant collections of entomological, geological and zoological specimens. Housed in a stunning Pre-Raphaelite-inspired example of neo-Gothic architecture, the Museum’s growing collections underpin a broad programme of natural environment research, teaching and public engagement.  

    www.oumnh.ox.ac.uk  

    www.morethanadodo.com  

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    University of Oxford

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  • Insular dwarfs and giants more likely to go extinct

    Insular dwarfs and giants more likely to go extinct

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    Newswise — Leipzig/Halle. Islands are “laboratories of evolution” and home to animal species with many unique features, including dwarfs that evolved to very small sizes compared to their mainland relatives, and giants that evolved to large sizes. A team of researchers from the German Centre of Integrative Biodiversity Research (iDiv) and Martin Luther University Halle-Wittenberg (MLU) has now found that species that evolved to more extreme body sizes compared to their mainland relatives have a higher risk of extinction than those that evolved to less extreme sizes. Their study, which was published in Science, also shows that extinction rates of mammals on islands worldwide increased significantly after the arrival of modern humans.

    Islands are hotspots for biodiversity – they cover less than 7% of the Earth’s land area, but account for up to 20% of all terrestrial species on the planet. However, islands are also hotspots for species extinction as 50% of today’s IUCN threatened species are native to islands.

    In response to the unique characteristics of island environments, many organisms undergo remarkable evolutionary changes, among the most notable of which include extreme modifications of body size. This phenomenon is known as gigantism or dwarfism – in general, relatives of large continental species tend to become smaller on islands and small species tend to become larger. Some of these are already extinct evolutionary marvels such as dwarf mammoths and hippos that shrunk to less than one-tenth the size of their mainland ancestors, and rodents and gymnures of unusual size that increased by over 100-fold. These also include dwarf and giant species currently threatened with extinction, such as the tamaraw of Mindoro (Bubalus mindorensis), a dwarf buffalo with a shoulder height of approximately 100 cm, and the giant Jamaican hutia (Geocapromys brownii), a rat-like mammal about the size of a rabbit.

    A team of researchers led by iDiv and MLU now confirmed that evolution towards these features frequently goes hand in hand with increased susceptibility to extinctions. “On the one hand, phyletic giants might provide bigger reward for hunting”, explains Dr Roberto Rozzi, former postdoctoral researcher at iDiv’s synthesis centre sDiv and at the Berlin Museum of Natural History, and now Curator of Palaeontology at the ZNS of Martin Luther University Halle-Wittenberg. “On the other hand, dwarfed species seem to have less deterrence power, facilitating hunting or predation by introduced predators.”

    Higher extinction risk of extreme dwarfs and giants

    To quantify how evolution towards dwarfism and gigantism may have affected the risk and rate of extinction (before and after human arrival), the researchers used data on fossil and living island mammals including over 1,200 extant and 350 extinct species of insular mammals on 182 islands and paleo-islands (formerly isolated landmasses that are now part of the mainland areas) worldwide.

    Their findings indicate a previously unknown result that those species that underwent more extreme body size shifts, either larger or smaller, were more likely to be endangered or to go extinct on islands. Comparison between the two directions of body size change showed that insular giant species have a slightly higher extinction risk than insular dwarfs. However, this difference was only significant when extinct species were included. Since the European expansion around the globe, extinctions have similarly affected dwarfed and giant insular mammals. “This likely reflects the impact of more intense and multifaceted human pressures, such as overexploitation and accelerated habitat loss, but also introductions of novel diseases and invasive predators”, says Dr Roberto Rozzi.

    Overlap of human colonization and increased extinction rates of insular mammals

    The researchers also analyzed the global fossil record of mammals on islands over the last 23 million years (late Cenozoic) and found a clear correlation between island extinctions at a global level and the arrival of modern humans. “We recorded an abrupt shift in the extinction regime from pre-sapiens to sapiens-dominated island ecosystems. Time overlap of insular mammals with H. sapiens increased their extinction rates more than 10-fold. However, our results at the global level do not rule out the concomitant contribution of environmental drivers such as climate change on local extinctions of island mammals”, says senior author Prof Jonathan Chase from iDiv and MLU. “While it is important to acquire more paleontological field data to further refine extinction chronologies, conservation agendas should, at the same time, give special priority to protecting the most extreme insular giants and dwarfs, many of which are already threatened with extinction.”

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    German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig

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