Tag Archives: Hadrosaur

A rare and painful tumor that affects humans was found in a 66-million-year-old dinosaur

Hadrosaurs roamed in packs. Credit: Kobayashi Y., et al, Scientific Reports.

Israeli researchers at Tel Aviv University investigated some peculiar cavities in the tail fossils of a hadrosaur, a duck-billed dinosaur that was excavated from Canada’s Dinosaur Provincial Park. Much to their amazement, these cavities were nearly identical to those formed in humans as a result of a rare, cancer-like disease.

Dinosaurs got sick too

The dinosaur fossils were first investigated using high-resolution computer tomography (CT) scans, which enabled the researchers to form a highly accurate image of the hadrosaur’s tail vertebrae without actually disturbing the specimen. When the CT scans were compared to the bones of two humans, known to suffer from a benign tumor called Langerhans cell histiocytosis (LCH), the researchers were amazed by how well the cavities matched.

“The micro-CT produces very high-resolution imaging, up to a few microns,” Dr. Hila May of the Department of Anatomy and Anthropology at Tel Aviv University said in a statement. “We scanned the dinosaur vertebrae and created a computerized 3D reconstruction of the tumor and the blood vessels that fed it. The micro and macro analyses confirmed that it was, in fact, LCH. This is the first time this disease has been identified in a dinosaur.”

LCH causes distinct lesions in the bones and is sometimes described as a rare form of cancer, although this is a somewhat controversial claim since the disease seems to appear and disappear spontaneously. Most of these tumors, which can be extremely painful to live with, appear out of the blue in the bones of children aged 2-10 years. However, most of the cases disappear in time without any intervention.

Hadrosaurs are a kind of duck-billed dinosaur and one of the most common herbivores of the Cretaceous. Their fossils are also among the most common in the record. What’s more, they’re generally so well-preserved that paleontologists have been able to calculate the dinosaurs’ muscle mass, learning that hadrosaurs were very muscular, likely having the ability to outrun predators. There’s even a so-called “Dakota” specimen, which was unearthed in such good condition that it looks more like a mummy than a fossil — researchers were even able to analyze its ligaments, tendons, and what may be internal organs through a CT scan. 

Now, this new study shows that these dinosaurs may have been affected by the same diseases as humans. Previously, other studies found that T. rex suffered from gout and that iguanodons could get osteoarthritis.

Many animals are affected by disease and there’s no reason to believe dinosaurs were any different. However, finding evidence of ancient diseases in dinosaurs is an entirely different matter due to the many challenges involved in identifying telltale signs of in the fossil record.

Photograph of the larger hadrosaur vertebra in lateral view (left) and caudal view (right). The space that contained the overgrowth opens to the caudal surface of the vertebra. Credit: Assaf Ehrenreich, Sackler Faculty of Medicine, Tel Aviv University.

The authors of the new study claim that their new findings will help improve our understanding of paleopathology, a field of science focused on studying disease and infection in the fossil record.

Although extremely rare, signs of disease in dinosaurs could also provide invaluable insights into how diseases evolved alongside animals. Many diseases affecting humans first appear in animals — among them the now-famous Wuhan coronavirus, which likely jumped to humans from snakes.

“These kinds of studies, which are now possible thanks to innovative technology, make an important and interesting contribution to evolutionary medicine, a relatively new field of research that investigates the development and behavior of diseases over time,” notes Prof. Israel Hershkovitz of Tel Aviv University. “We are trying to understand why certain diseases survive evolution with an eye to deciphering what causes them in order to develop new and effective ways of treating them.”

The findings appeared in the journal Scientific Reports.

Aquilarhinus palimentus. Credit: ICRA Art.

Scientists discover new eagle-nosed, shovel-chinned dinosaur

Paleontologists have recently described a weird looking 80-million-year-old dinosaur with an “eagle-nose” and “shovel-chin”. The dinosaur is one of the earliest hadrosaurs, also known as duck-billed dinosaurs, found thus far.

Aquilarhinus palimentus. Credit: ICRA Art.

Aquilarhinus palimentus. Credit: ICRA Art.

The skull and partial skeleton of the specimen were first discovered in the 1980s, in Texas’ Big Bend National Park. However, it was only recently that paleontologists at the Catalan Institute of Palaeontology Miquel Crusafont in Barcelona, Spain, analyzed the duck-billed herbivore in more detail.

Around the time of its discovery, other researchers posited that the dinosaur’s skull and characteristic nasal crest belonged to another hadrosaur, called Groposaurus. The new analysis, however, shows that while the dinosaur had a bony crest on its skull, just like many other hadrosaurs, it also had unique, shovel-like jaws. For instance, the lower jaws of the dinosaur meet in a peculiar W-shape, creating a wide, flattened scoop.

Artist impression depicting what Aquilarhinus palimentus may have looked like. Credit: ICRA Art.

Writing in the Journal of Systematic Palaeontology, the team of paleontologists reports that the specimen belongs to previously unreported new species of crested dinosaurs and that it does not fit with the main group of duck-billed dinosaurs known as Saurolophidae. The authors unceremoniously named the dinosaur Aquilarhinus palimentus, where “aquila” means eagle in Latin and “rhinos” means “nose” in Greek, whereas “palimentus” combines the Latin words for “shovel” and “chin”. In other words, the Catalan paleontologists literally called the dinosaur Eagle-nosed Shovel-chin. Take that, T. rex!

Since A. palimentus has more primitive features than its subsequent cousins, the researchers think that their study might offer new clues as to how the group’s crests evolved. Some scholars believe that the nasal crest helped hadrosaurs identify members from the group and compete for mates. The scooping chin was probably useful more than 80 million years ago when Texas used to be a marsh. Aquilarhinus‘ jaws must have come in handy for scooping vegetation from the bottom of the muddy creek bed.

The dentary of Aquilarhinus, showing the unusual upturned end of the mandible. Credit: Albert Prieto-Marquez.

The dentary of Aquilarhinus, showing the unusual upturned end of the mandible. Credit: Albert Prieto-Marquez.

Hadrosaurs were mostly found in Europe, Asia, North and South America, and Antarctica during the late Cretaceous period. However, such a primitive specimen supports the idea that hadrosaurs first appeared in the southern part of North America.

“This new animal is one of the more primitive hadrosaurids known and can therefore help us to understand how and why the ornamentation on their heads evolved, as well as where the group initially evolved and migrated from,” says lead author Dr. Albert Prieto-Márquez from the Institut Català de Paleontologia Miquel Crusafont, near Barcelona. “Its existence adds another piece of evidence to the growing hypothesis, still up in the air, that the group began in the southeastern area of the US.”

New Hadrosauroid.

New species of duck-billed dinosaur discovered in the Gobi Desert

A fossilized, nearly-intact dinosaur skeleton unearthed in Mongolia fills a gap in the evolution of hadrosaurs.

New Hadrosauroid.

Skeletal reconstructions of Gobihadros mongoliensis.
Image credits Tsogtbaatar et al,, (2019), PLOS ONE.

Researchers from the Mongolian Academy of Science and the Royal Ontario Museum, funded by the Hayashibara Museum of Natural Sciences, describe a new species closely related to Hadrosaurids, which they named Gobihadros mongoliensis. The new species will help us better understand the evolution and ecology of the dinosaur family Hadrosauridae, the ‘duck-billed’ dinosaurs.

Quak

“The article describes, for the first time, extraordinary well-preserved fossil material of hadrosauroid dinosaur as a new genus and species from the early Late Cretaceous in Mongolia. We hope that it will be very useful material for further study of the evolution of hadrosauroids, iguanodintians and ornithopods as well,” the authors write.

Duck-billed dinosaurs were quite successful during their day in the Late Cretaceous. They had a wide geographical range over the world as it was at the time and were important large herbivores in their ecosystem. But we don’t really know much about the species during its early days. Some partial fossils found previously are helping us piece together the duck-billed dinos’ family tree, but complete fossils remain few and far between.

Gobihadros mongoliensis was discovered at the Bayshin Tsav Site in the Gobi Desert, Mongolia. Several specimens were found at the site, including one “virtually complete” skeleton measuring almost three meters in length. Anatomical comparisons to Hadrosauridae fossils revealed that this species doesn’t quite fit into the family. The species, however, are very closely related. Gobihadros is the first hadrosaur-like dinosaur from the Late Cretaceous of central Asia known from complete remains.

The team also reports, based on comparisons to later Asian hadrosaurs, that Gobihadros would not make it through the natural-selection gauntlet. Later Asian hadrosaurs are related to species in today’s North America, and likely migrated from there during the Late Cretaceous. The authors caution that we need more fossils from this transition period in order to get a proper idea of what happened — and when. But, from the data we have now, Gobihadros seems to have disappeared from Asia and was soon followed by the hadrosaurs. This suggests that the hadrosaurs ultimately outcompeted species like Gobihadros.

“[…] the relationships of other taxa are well-resolved, and in combination with biostratigraphic data, suggest that hadrosaurids from the Maastricthian of Asia migrated from North America across Beringia in the Campanian, and replaced non-hadrosaurids such as Gobihadros,” the authors conclude.

The paper “A new hadrosauroid (Dinosauria: Ornithopoda) from the Late Cretaceous Baynshire Formation of the Gobi Desert (Mongolia)” has been published in the journal PLoS ONE.

Vegetarian dinosaurs sometimes feasted on crustaceans

The idea of a strictly vegetarian dinosaur has been called into question as researchers found evidence of shellfish eating.

Skin impressions are known in Parasaruolophus, a hadrosaur. The hadrosaurs are known for their particular skull shape. Image credits: Steveoc 86 / Wikipedia.

Our understanding of how and what dinosaurs ate is still simplistic. Largely speaking, we have the plant-eaters and the meat-eaters, but things might be much more nuanced than what we originally thought. Now, researchers have found evidence of Hadrosaurs eating crabs and other crustaceans, a behavior linked to mating behaviors.

Hadrosaurs are a kind of duck-billed dinosaur and one of the most common herbivores of the Cretaceous. Hadrosaur fossils are so common and so well-preserved that paleontologists have been able to calculate their muscle mass, learning that hadrosaurs were very muscular, likely having the ability to outrun predators. The so-called “Dakota” specimen was in such good condition that researchers were even able to analyze its ligaments, tendons, and possibly some internal organs through a CT scan. If anything, “Dakota” is more a mummy than a fossil. But we still have a long way to go before we can say we get hadrosaurs.

Dr. Karen Chin of the University of Colorado, Boulder, US, led a team which discovered and analyzed hadrosaur droppings which contained pieces of crabs and other crustaceans — but only during some times of the year.

“I immediately said, ‘Oh, no, no, it can’t be crustaceans.’ That was my knee jerk reaction,” Karen Chin tells The Two-Way. She’s the curator of paleontology at University of Colorado Boulder’s Museum of Natural History and a co-author of the paper published today in Scientific Reports.

“I was very surprised but I think it reminds us that there’s a lot we just don’t know about the behavior of ancient animals,” she said.

The surface of knobby crustacean shell fragment embedded in fossilized feces samples from Grand Staircase-Escalante National Monument in Utah. Karen Chin/Denver Museum of Nature & Science.

The crustaceans weren’t accidentally ingested. Crustaceans were found in 10 of the 15 studies places, spread over a 20-kilometer area and potentially over hundreds of years. “This was definitely a recurring diet,” Chin says. The droppings also contained wood pieces, which indicates that the crustaceans lived around (probably rotting) logs. They were also “good-sized crustaceans,” measuring at least five centimeters, which indicates that hadrosaurs chose to eat them.

“The fact that these crustaceans were a fair percentage of the width of the skull of the dinosaurs [means] they would have had a choice to reject it if it wasn’t either a desired or acceptable food source.”

The team proposes that the dinosaurs ate the crustaceans to complement their diet during the mating season, when they need large amounts of both protein and calcium, especially during the egg laying period. If this is the case, it could mean that the behavior is also shared by other herbivores, such as the mighty triceratops or the mace-tailed stegosaurus. Perhaps this isn’t really that surprising when you think about. This behavior is also common in today’s herbivores. Usually, they feast on plants but every now and then, they eat something else to complement their diet (either accidentally or intentionally).

“And knowing that at least some of them – we can’t say all of them at this point – but at least some of them occasionally varied their diet to eat more animal products is really intriguing.”

Whatever the case may be, we definitely have to fine tune our idea of herbivore dinosaurs. The classic image of a gentle giant munching on foliage all day long might simply not be true.

Journal Reference: Karen Chin, Rodney M. Feldmann & Jessica N. Tashman. Consumption of crustaceans by megaherbivorous dinosaurs: dietary flexibility and dinosaur life history strategiesdoi:10.1038/s41598-017-11538-w

New species of duck-billed dinosaur discovered in Alaska’s North Slope

A new species of plant-eating dinosaur was discovered in Alaska, a variety of hadrosaur — duck-billed dinos that roamed in herds, said Pat Druckenmiller, earth sciences curator at the University of Alaska Museum in Fairbanks. Researchers named the creature Ugrunaaluk kuukpikensis (oo-GROO’-nah-luk KOOK’-pik-en-sis), meaning “ancient grazer,” chosen by scientists with assistance from speakers of Inupiaq, the language of Alaska Inupiat Eskimos.

The presence of this dinosaur suggests that northern Alaska was likely warmer and covered in forests some 69 million years ago — that’s how old the stone deposits that preserved its bones were. For at least 25 years, the fossils stayed lumped together with another hadrosaur, Edmontosaurus, a species that spread wide across Canada and the U.S., including Montana and South Dakota. The formal study of the Alaska dinosaur revealed differences in skull and mouth features that made it a different species, Druckenmiller said.

Researchers at the University of Alaska Fairbanks have found a third distinct dinosaur species documented on Alaska’s oil-rich North Slope. The new species is a type of hadrosaur, a duck-billed plant-eater.
Image via al.com

The differences were not immediately apparent because the Alaska dinosaurs were juveniles. Researchers worked out differences in the Alaska fossils by plotting growth trajectories and by comparing them with juvenile Edmontosourus bones. Museum scientists have excavated and catalogued more than 6,000 bones from the species, more than any other Alaska dinosaur. Most were small juveniles estimated to have been about 9 feet long and 3-feet tall at the hips.

“It appears that a herd of young animals was killed suddenly, wiping out mostly one similar-aged population to create this deposit,” Druckenmiller said.

At their biggest, they would grow up to 30 feet long, and dined on coarse vegetation using hundreds of hardy teeth. They probably walked primarily on their hind legs, but they could drop to all fours to escape predators or if the terrain got rough, he added.

Most of the fossils were found in the Prince Creek Formation of the Liscomb Bone Bed along the Colville River more than 300 miles northwest of Fairbanks. The bed is named for geologist Robert Liscomb, who found the first dinosaur bones in Alaska in 1961 while mapping for Shell Oil Co.

Researchers are now working to identify and name other Alaskan dinosaurs.

“We know that there’s at least 12 to 13 distinct species of dinosaurs on the North Slope in northern Alaska,” he said. “But not all of the material we find is adequate enough to actually name a new species.”