New details of Tully monster revealed

The Tully monster.
Discovered in the 1950s and first described in a paper in 1966, the Tully monster, with its stalked eyes and long proboscis, is difficult to compare to all other known animal groups. Unique to Illinois in the U.S., it became its state fossil in 1989.
Image Credit: © 2023 Takahiro Sakono

For more than half a century, the Tully monster (Tullimonstrum gregarium), an enigmatic animal that lived about 300 million years ago, has confounded paleontologists, with its strange anatomy making it difficult to classify. Recently, a group of researchers proposed a hypothesis that Tullimonstrum was a vertebrate similar to cyclostomes (jawless fish like lamprey and hagfish). If it was, then the Tully monster would potentially fill a gap in the evolutionary history of early vertebrates. Studies so far have both supported and rejected this hypothesis. Now, using 3D imaging technology, a team in Japan believes it has found the answer after uncovering detailed characteristics of the Tully monster which strongly suggest that it was not a vertebrate. However, its exact classification and what type of invertebrate it was is still to be decided.

In the 1950s, Francis Tully was enjoying his hobby fossil hunting in a site known as Mazon Creek Lagerstätte in the U.S. state of Illinois, when he discovered what would later become known as the Tully monster. This 15-centimeter (on average), 300-million-year-old marine “monster” turned out to be an enigma, as ever since its discovery researchers have debated where it fits in the classification of living things (its taxonomic position). Unlike dinosaur bones and hard-shelled creatures that are often found as fossils, the Tully monster was soft-bodied. The Mazon Creek Lagerstätte is one of the few places in the world where the conditions were just right for imprints of these marine animals to be captured in detail in the underwater mud, before they could decay. In 2016, a group of scientists in the US proposed a hypothesis that the Tully monster was a vertebrate. If this was the case, then it could be a missing piece of the puzzle on how vertebrates evolved.

Apes may have evolved upright stature for leaves, not fruit, in open woodland habitats

Artistic rendering of the open woodland habitat reconstruction at Moroto II with Morotopithecus bishopi vertically climbing with infant on back and juvenile below. Active volcano (Mount Moroto) is in background. Fossil relative of an elephant (Prodeinotherium) is foraging in center back.
Illustration Credit: Corbin Rainbolt

Anthropologists have long thought that our ape ancestors evolved an upright torso in order to pick fruit in forests, but new research from the University of Michigan suggests a life in open woodlands and a diet that included leaves drove apes’ upright stature.

The findings shed light on ape origins and push back the origin of grassy woodlands from between 7 million and 10 million years ago to 21 million years ago in equatorial Africa, during the Early Miocene.

Fruit grows on the spindly peripheries of trees. To reach it, large apes need to distribute their weight on branches stemming from the trunk, then reach out with their hands toward their prize. This is much easier if an ape is upright because it can more easily grab onto different branches with its hands and feet. If its back is horizontal, then its hands and feet are generally underneath the body, making it much harder to move outward to the smaller branches of a tree—especially if the ape is large bodied.

Small and simple key to evolution success of mammals

Artistic reconstruction of early mammal ancestors (species: Hadrocodium wui) shown hunting insect prey, illustrating how the adoption of an insectivorous diet and miniaturization played an important role in mammal evolution.
Illustration Credit: Dr Stephan Lautenschlager, University of Birmingham

Ancestors of modern mammals evolved into one of the most successful animal lineages by starting out small and simple, researchers have found.

A new study, published today in Communications Biology, shows that skull bones were successively reduced in early mammals around 150 to 100 million years ago.  

The research further demonstrated that alongside the reduction of skull bones, early mammals also became a lot smaller, some of which had a skull length of only 10-12 mm. This miniaturization considerably restricted the available food sources and early mammals adapted to feeding mostly on insects, allowing them to thrive in the shadows of dinosaurs.

In many vertebrate groups (animals with a back bone), such as fishes and reptiles, the skull and lower jaw are composed of numerous bones. This was also the case in the earliest ancestors of modern mammals over 300 million years ago.

95-million-year-old sauropod dinosaur skull first of its kind in Australia

Diamantinasaurus matildae head.
Illustration Credit: Elena Marian/ Australian Age of Dinosaurs Musuem of Natural History

A Curtin University-led research team has analyzed Australia’s first nearly complete sauropod dinosaur skull found in Queensland, Australia, gaining a better understanding of the animal’s anatomy, relationships to other sauropods, and feeding habits.

The research, published in Royal Society Open Science and completed in collaboration with the Australian Age of Dinosaurs Museum of Natural History, found that the skull – belonging to a dinosaur nicknamed ‘Ann’ – was from the species Diamantinasaurus matildae. Diamantinasaurus is a member of the dinosaur group Sauropoda, known for having small heads, long necks and tails, barrel-like bodies, and four columnar legs.

Lead researcher and paleontologist Dr Stephen Poropat, from Curtin’s School of Earth and Planetary Sciences, said ‘Ann’ is the first sauropod dinosaur found in Australia to include most of the skull, and also the first Diamantinasaurus specimen to preserve a back foot.

“I was lucky enough to be involved in this Australian-first discovery. Being able to lead the research on these fossils was a huge privilege. This skull gives us a rare glimpse into the anatomy of this enormous sauropod that lived in northeast Australia almost 100 million years ago,” Dr Poropat said.

Predatory dinosaurs such as T. rex sported lizard-like lips

A juvenile Edmontosaurus disappears into the enormous, lipped mouth of Tyrannosaurus.
Illustration Credit Dr Mark Witton

A new study suggests that predatory dinosaurs, such as Tyrannosaurus rex, did not have permanently exposed teeth as depicted in films such as Jurassic Park, but instead had scaly, lizard-like lips covering and sealing their mouths.

Researchers and artists have debated whether theropod dinosaurs, the group of two-legged dinosaurs that includes carnivores and top predators like T. rex and Velociraptor, as well as birds, had lipless mouths where perpetually visible upper teeth hung over their lower jaws, similar to the mouth of a crocodile.

However, an international team of researchers challenge some of the best-known depictions, and say these dinosaurs had lips similar to those of lizards and their relative, the tuatara - a rare reptile found only in New Zealand, which are the last survivors of an order of reptiles that thrived in the age of the dinosaurs.

In the most detailed study of this issue yet, the researchers examined the tooth structure, wear patterns and jaw morphology of lipped and lipless reptile groups and found that theropod mouth anatomy and functionality resembles that of lizards more than crocodiles. This implies lizard-like oral tissues, including scaly lips covering their teeth.

“Exquisite” sabertooth skull offers clues about Ice Age predator

Dave Easterla, left, Distinguished University Professor Emeritus of Biology at Northwest Missouri State University and Matthew Hill, associate professor of anthropology at Iowa State, with a fossilized complete skull from a sabertooth cat from southwest Iowa.
Photo Credit: Christopher Gannon/Iowa State University.

The recent discovery of a sabertooth cat skull in southwest Iowa is the first evidence the prehistoric predator once inhabited the state.

The chance of finding any fossilized remains from a sabertooth cat is slim, said Matthew Hill, an associate professor of archaeology at Iowa State and expert on animal bones. The remarkably well-preserved skull found in Page County is even rarer, and its discovery offers clues about the iconic Ice Age species before its extinction roughly 12-13,000 years ago.

“The skull is a really big deal,” said Hill. “Finds of this animal are widely scattered and usually represented by an isolated tooth or bone. This skull from the East Nishnabotna River is in near perfect condition. It’s exquisite.”

Hill analyzed the specimen in collaboration with David Easterla, Distinguished University Professor Emeritus of Biology at Northwest Missouri State University. Their findings are newly published in Quaternary Science Reviews.

Extinction of steam locomotives derails assumptions about biological evolution

The Union Pacific Big Boy Steam Engine (one of the largest steam engines ever built and still functioning) visited Lawrence on Sept. 2, 2021.
Photo Credit: Bruce Lieberman

When the Kinks’ Ray Davies penned the tune “Last of the Steam-Powered Trains,” the vanishing locomotives stood as nostalgic symbols of a simpler English life. But for a paleontologist at the University of Kansas, the replacement of steam-powered trains with diesel and electric engines, as well as cars and trucks, might be a model of how some species in the fossil record died out.

Bruce Lieberman, professor of ecology & evolutionary biology and senior curator of invertebrate paleontology at the KU Biodiversity Institute & Natural History Museum, sought to use steam-engine history to test the merits of “competitive exclusion,” a long-held idea in paleontology that species can drive other species to extinction through competition.

Working with former KU postdoctoral researcher Luke Strotz, now of Northwest University in Xi’an, China, Lieberman found the fossil record largely lacks the detailed data verifying competitive exclusion found in the history of steam engines: “It's really hard to actually see any evidence that competition does play a big role in evolution,” Lieberman said.

Their findings have just been published in the paper “The end of the line: competitive exclusion and the extinction of historical entities2” in the peer-reviewed journal Royal Society Open Science.

Beaver Fossil Named After Buc-ee’s

Matthew Brown (left) and Steve May with beaver skulls new and old in the vertebrate paleontology collections at the Jackson School of Geosciences. Brown, the director of the collections, holds a skull from a modern North American Beaver. May, a research associate, holds a skull from Anchitheriomys buceei, a new species of ancient beaver that he discovered in the collections and named.
Photo Credit: UT Jackson School of Geosciences.

A new species of ancient beaver that was rediscovered by researchers in The University of Texas Austin’s fossil collections has been named after Buc-ee’s, a Texas-based chain of popular travel centers known for its cartoon beaver mascot.

The beaver is called Anchitheriomys buceei, or “A. buceei” for short.

Steve May, a research associate at the UT Jackson School of Geosciences, said that the beaver’s Texas connection and a chance encounter with a Buc-ee’s billboard are what inspired the name.

May is the lead author of the paper that describes A. buceei, along with another, much smaller, species of fossil beaver. Published in the journal Palaeontologia Electronica, the paper provides an overview of beaver occurrences along the Texas Gulf Coast from 15 million to 22 million years ago based on bones and archival records in the UT collections.

While driving down a highway in 2020, May spotted a Buc-ee’s billboard that said “This is Beaver Country.” The phrase brought to mind the Texas beaver fossils he had been studying at UT’s Texas Vertebrate Paleontology Collections.

New Fossil Analysis Reveals Dinosaur with Record-Holding 15-Meter-Long Neck

 A rendering of the sauropod known as Mamenchisaurus sinocanadorum, which had a 15-meter-long neck, about 10 feet longer than a typical school bus.
Illustration Credit: Júlia d'Oliveira

Scientific Frontline: "At a Glance" Summary: Mamenchisaurus sinocanadorum Neck Analysis

• Main Discovery: Paleontologists determined that the Late Jurassic Chinese sauropod Mamenchisaurus sinocanadorum possessed a 15-meter-long neck, setting a new record for the longest neck confidently inferred for any known sauropod.
• Methodology: Researchers utilized computed-tomography scanning to examine fragmented fossilized neck and skull bones, subsequently reconstructing the dinosaur's evolutionary relationships and comparing its structure to more complete skeletons of its closest relatives.
• Key Data: The reconstructed neck measured approximately 15.1 meters (49.5 feet) in length. The vertebrae consisted of 69 to 77 percent air by volume and were stabilized by 4-meter-long rod-like cervical ribs.
• Significance: The study provides critical biomechanical insights into how sauropods achieved massive body sizes and supported extreme anatomical structures without skeletal collapse, demonstrating the structural viability of quadrupedal gigantism.
• Future Application: This comparative structural framework enables scientists to more accurately interpret fragmentary fossil records and model the physical and biomechanical limits of extinct megastructures.
• Branch of Science: Paleontology, Evolutionary Biology, Biomechanics.
• Additional Detail: The extreme neck length allowed the dinosaur to feed efficiently by reaching foliage up to 10 meters above the ground from a stationary position, while the expanded surface area likely assisted in dissipating excess body heat.

Why are mammals more likely to go extinct on islands than on the mainland?

Illustration of Sardinian Dwarf Mammoth, Sardinian Giant Otter, Deer, Sardinian Dhole and Giant Pica
 Illustration Credit: Peter Schouten

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. 

Dinosaur claws used for digging and display

Therizinosaurs claw hooking and pulling trees
Image Credit: Shuyang Zhou for the 3D modelling and functional scenario restoration

Dinosaur claws had many functions, but now a team from the University of Bristol and the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) in Beijing has shown some predatory dinosaurs used their claws for digging or even for display.

The study focused on two groups of theropod dinosaurs, the alvarezsaurs and therizinosaurs, that had weird claws whose function had been a mystery up to now. It turns out that alvarezsaurs used their rock-pick-like claws for digging, but their close relatives, the giant therizinosaurs, used their overdeveloped, meter-long, sickle-like claws for display.

The new work is led by Zichuan Qin, a PhD student at the University of Bristol and the IVPP. He developed a new, computational approach in biomechanics to identify functions based on detailed comparison with living animals. First, the claws were modelled in three dimensions from CT scans, then modelled for stress and strain using engineering methods, and finally matched to functions of pulling, piercing and digging by comparison with modern animals whose claw functions are known.

“Alvarezsaurs and therizinosaurs are definitely the strangest cousins among dinosaurs,” said Professor Michael Benton, one of Zichuan’s supervisors. “Alvarezsaurs were the tiniest dinosaurs ever, the size of chickens, with stubby forelimbs and robust single claws, but their closest relative, the therizinosaurs, evolved in the exact opposite path.”

Researchers solve a 150-year-old mystery

A reconstruction - of the aetosaur assemblage in its habitat.
Illustration Credits: © J. Kowalski (drawing) and P. Janecki (coloring)

The Aetosaurs had a small head and a crocodile-like body. The land dwellers were up to six meters long and widely distributed geographically. They died out about 204 million years ago, at the end of the Triassic. In Kaltental near Stuttgart, Germany, an assemblage of 24 Aetosaurus ferratus individuals, only between 20 and 82 centimeters long, was discovered in 1877. Since then, scientists have been puzzling over whether they were juveniles or small adults. A team led by Elżbieta M. Teschner from the University of Bonn has now solved the mystery: Bone examination of two specimens shows that they are juveniles. The results have now been published in the Journal of Vertebrate Paleontology.

Reptiles of the genus Aetosaurus ferratus were discovered in a quarry near Kaltental, now a district of Stuttgart, and were first described nearly 150 years ago. The assemblage of about 24 individuals was dated to be about 215 million years old. "What was striking was that the total body length was only between 20 and 82 centimeters," says Elżbieta M. Teschner, who is pursuing a doctorate in paleontology at the University of Bonn while also conducting research at the University of Opole (Poland). "Interestingly, they were also the only fossils found in the area," she adds.

319-million-year-old fish preserves the earliest fossilized brain of a backboned animal

 

Video Credit: University of Michigan

The CT-scanned skull of a 319-million-year-old fossilized fish, pulled from a coal mine in England more than a century ago, has revealed the oldest example of a well-preserved vertebrate brain.

The brain and its cranial nerves are roughly an inch long and belong to an extinct bluegill-size fish. The discovery opens a window into the neural anatomy and early evolution of the major group of fishes alive today, the ray-finned fishes, according to the authors of a University of Michigan-led study scheduled for publication Feb. 1 in Nature.

The serendipitous find also provides insights into the preservation of soft parts in fossils of backboned animals. Most of the animal fossils in museum collections were formed from hard body parts such as bones, teeth and shells.

The CT-scanned brain analyzed for the new study belongs to Coccocephalus wildi, an early ray-finned fish that swam in an estuary and likely dined on small crustaceans, aquatic insects and cephalopods, a group that today includes squid, octopuses and cuttlefish. Ray-finned fishes have backbones and fins supported by bony rods called rays.

Fossils of Arctic primate relatives tell climate-adaptation story

Artist's reconstruction of Ignacius dawsonae surviving six months of winter darkness in the extinct warm temperate ecosystem of Ellesmere Island, Arctic Canada.
Illustration Credit: Kristen Miller, Biodiversity Institute, University of Kansas.

Two sister species of near-primate, called “primatomorphans,” dating back about 52 million years have been identified by researchers at the University of Kansas as the oldest to have dwelled north of the Arctic Circle. The findings was published in the peer-reviewed journal PLOS ONE.

According to lead author Kristen Miller, doctoral student with KU’s Biodiversity Institute and Natural History Museum, both species — Ignacius mckennai and I. dawsonae — descended from a common northbound ancestor who possessed a spirit “to boldly go where no primate has gone before.”

The specimens were discovered on Ellesmere Island, Nunavut, Canada, in layers of sediment linked with the early Eocene, an epoch of warmer temperatures that could foretell how ecosystems will fare in coming years due to human-driven climate change.

“No primate relative has ever been found at such extreme latitudes,” Miller said. “They’re more usually found around the equator in tropical regions. I was able to do a phylogenetic analysis, which helped me understand how the fossils from Ellesmere Island are related to species found in midlatitudes of North America — places like New Mexico, Colorado, Wyoming and Montana. Even down in Texas we have some fossils that belong to this family as well.”

Ancient chimaeras were suction feeders, not shell crushers, new research shows

Iniopera reconstruction
Resized Image using AI by SFLORG
Photo Credit: Richard Dearden / University of BIrmingham

A rare three-dimensional fossil of an ancient chimaera has revealed new clues about the diversity of these creatures in the Carboniferous period, some 300 million years ago.

Research led by the Muséum national d'histoire naturelle (MNHN) and the University of Birmingham has shown that an ancient relative of chimaeras – jawed vertebrates that are related to sharks and rays – fed by sucking in prey animals underwater.

The fossil, from a genus called Iniopera, is the only suction feeder to be identified among chimaeras, and quite different from living chimaeras, which feed by crushing mollusks and other hard-shelled prey between their teeth. The research is published in the journal PNAS.

‘Veggie’ dinosaurs differed in how they ate their food

Some of the finite element models compared bite performance across the five ornithischian dinosaurs in the study, with different models showing different bite points. Cooler colors (blue) represent areas of low stress while hot colors (red and pink) indicate areas that are highly stressed.
Illustration Credit: David Button

Although most early dinosaurs were vegetarian, there were a surprising number of differences in the way that these animals tackled eating a plant-based diet, according to a new study by scientists from the Natural History Museum and the Universities of Bristol and Birmingham.

Scientists used CT scans of dinosaur skulls to track the evolution of early dinosaur herbivores - reconstructing jaw muscles and measuring the animals’ bite force to understand how dinosaur feeding evolved.

Five skulls from the plant-eating group Ornithischia provided the key to unlocking their feeding habits: Heterodontosaurus, Lesothosaurus, Scelidosaurus, Hypsilophodon and Psittacosaurus - earliest representatives of what would become the major herbivore dinosaur groups.

Later ornithischian dinosaurs, like Triceratops and Stegosaurus, show a wide range of adaptations to eating plants yet their early relatives have not been examined properly, until now.

Fossil CSI: Mysterious site was ancient birthing grounds

Adult and young of the ichthyosaur species Shonisaurus popularis chase ammonoid prey 230 million years ago, in what is now Berlin-Ichthyosaur State Park, Nevada, U.S.A.
Illustration Credit: Gabriel Ugueto 

Today’s marine giants—such as blue and humpback whales—routinely make massive migrations across the ocean to breed and give birth in waters where predators are scarce, with many congregating year after year along the same stretches of coastline. Now, new research from a team of scientists—including researchers with the University of Utah (Natural History Museum of Utah and Department of Geology & Geophysics), Smithsonian Institution, Vanderbilt University, University of Nevada, Reno, University of Edinburgh, University of Texas at Austin, Vrije Universiteit Brussels, and University of Oxford—suggests that nearly 200 million years before giant whales evolved, school bus-sized marine reptiles called ichthyosaurs may have been making similar migrations to breed and give birth together in relative safety.

The findings, published today in the journal Current Biology, examine a rich fossil bed in the renowned Berlin-Ichthyosaur State Park (BISP) in Nevada’s Humboldt-Toiyabe National Forest, where many 50-foot-long ichthyosaurs (Shonisaurus popularis) lay petrified in stone. Co-authored by Randall Irmis, NHMU chief curator and curator of paleontology, and associate professor, the study offers a plausible explanation as to how at least 37 of these marine reptiles came to meet their ends in the same locality—a question that has vexed paleontologists for more than half a century.

Scientists discover what was on the menu of the first dinosaurs

Early dinosaurs and their diets. Lesothosaurus is an omnivore, Buriolestes is a carnivore and Thecodontosaurus is an herbivore
Illustration Credit: Gabriel Ugueto

The earliest dinosaurs included carnivorous, omnivorous and herbivorous species, according to a team of University of Bristol paleobiologists.

By looking at the tooth shapes of the earliest dinosaurs and simulating their tooth function with computational modelling, experts were able to compare them to living reptiles and their diets. Their findings, published today in Science Advances, show that many groups of plant-eating dinosaurs were ancestrally omnivorous and that the ancestors of our famous long-necked herbivores, such as Diplodocus, ate meat. This ability to diversify their diets early in their evolution likely explains their evolutionary and ecological success.

The earliest dinosaurs are enigmatic: they were much smaller than their later relatives and for most of the Triassic they were in the shadow of crocodile-like reptiles. It is unknown how diverse they were in terms of diets and ecology, but scientists know something must have happened in the Triassic that allowed dinosaurs to endure the Triassic–Jurassic mass extinction and adapt in its aftermath, becoming the dominant group for the rest of the Mesozoic.

Fossil site reveals giant arthropods dominated the seas 470 million years ago

Fossils from the Fezouata Shale. From left to right, a non-mineralized arthropod (Marrellomorpha), a palaeoscolecid worm and a trilobites.
Image Credit Emmanuel Martin.

Discoveries at a major new fossil site in Morocco suggest giant arthropods – relatives of modern creatures including shrimps, insects and spiders – dominated the seas 470 million years ago.

Early evidence from the site at Taichoute, once undersea but now a desert, records numerous large “free-swimming” arthropods.

More research is needed to analyze these fragments, but based on previously described specimens, the giant arthropods could be up to 2m long.

An international research team says the site and its fossil record are very different from other previously described and studied Fezouata Shale sites from 80km away.

They say Taichoute (considered part of the wider “Fezouata Biota”) opens new avenues for paleontological and ecological research.

True giant wombat gives Diprotodon podium a wobble

Ramsayia reconstruction (r) next to a modern wombat.
Illustration Credit: Eleanor Pease, CC BY-NC

If you thought Australia was home to only one ancient ‘giant wombat’, think again.

While the Diprotodon – the extinct megafauna species that is distantly related to wombats but was the size of a small car – is commonly (but incorrectly) thought of as Australia’s ‘giant wombat’, researchers from Griffith University have shed light on a large species that does belong in the modern-day wombat family.

The complete skull of this true fossil giant wombat, found in a Rockhampton cave in Queensland and estimated to be around 80,000 years old, has been described for the first time by a team led by Associate Professor Julien Louys from Griffith’s Australian Research Centre for Human Evolution.