Scientists discover ‘mummies’ of horse-hoofed dinosaurs

It’s been more than 60 million years since duck-billed dinosaurs roamed what is now known as western North America.

Or, more accurately, since they were clustered around. On their hooves.

This, according to a new study of “dinosaur mummies” – fossils in which the external anatomy of dinosaurs is represented in incredible detail on thin layers of ancient soil.

This is the first time that hooves of a dinosaur, or indeed any reptile, have been found. But the researchers behind the discovery hope more will emerge now that people know how to look for them.

“I think people’s antennae will now try to make sure there’s nothing there when they’re digging,” said the study’s lead author, paleontologist Paul Sereno of the University of Chicago. as it happens Host Nil Koksal.

conclusion, Published in Science JournalPaint the most complete picture to date of what duck-billed dinosaurs really looked like.

Additionally, the study sheds light on the long-standing mystery of how these so-called dinosaur mummies came to be in the first place.

Cretaceous period cows

Duck-billed dinosaurs were far more common than their more famous contemporaries of the Cretaceous period, like the apex predator Tyrannosaurus, or the horned dinosaur Triceratops.

In fact, these were the favorite food of the plant-eating T. rex, about three meters long.

Also known as Edmontosaurus – because the first fossils were discovered in southern Alberta – they roamed together in huge herds, grazing on plants, like modern cows, sheep and goats.

Like today’s grazing mammals, these dinos evolved hooves, structures that protected their toes, supported their weight, provided traction and absorbed shock from the impact of walking and running for their lives.

“It’s remarkably similar to the hoof of a late horse or horse, or something you might see on a relative, a tapir or a rhinoceros,” Sereno said.

“There’s a shield around the outside, and then there’s like a soft core on the bottom that actually looks like the mammalian hoof that evolved much later.”

This is an example of a phenomenon known as convergent evolution, in which different organisms independently evolve similar features – such as the wings of birds, bats and extinct flying reptiles called pterosaurs – while adapting to similar environments or ecological niches.

What even is a dinosaur mummy?

Sereno and his colleagues identified hooves on a pair of elaborate fossils known as dinosaur mummies. They are skeletons that, at first glance, appear to be covered with remarkably well-preserved skin.

Scientists have been searching for these types of fossils for more than a century, many of them in the lowlands of eastern Wyoming, known as the “Mummy Zone.”

Sereno and his colleagues wanted to understand the process by which these mummies are created. But it turned out that this name was a bit wrong.

“People will think of Egyptian mummies and ask what is a dinosaur mummy? That was our question at first,” Sereno said.

Mummification refers to the preservation of flesh, usually intentionally or naturally. But it appears that these mummies are flesh-free.

The study looked at two duck-billed dinosaur fossils excavated in Wyoming in the early 2000s.

Sereno says the samples actually contain no skin, DNA, or tissue.

It’s just mud.

Two Edmontosaurus died about 66 million years ago, possibly in droughtd Their dried corpses were covered by flash floods, encasing them in a film of soil about 0.025 cm thick.

Then that soil became hard with the help of microbes. When the skin and flesh decayed, it left bones encased in clay masks that preserved the creatures’ shape, including the shape of their bodies and scaly skin.

“It’s a beautiful rendition of what this animal looked like,” Sereno said.

This style of mummification has preserved other organisms before, but scientists didn’t think it could happen on land. It’s possible that other mummies found at the Wyoming site were made in a similar manner, Sereno said.

united nationsMateusz Wosik, a paleontologist at the University of Misericordia who was not involved in the discovery, says understanding how dinosaur mummies are formed could help scientists uncover more of them. It is important to look not only at the dinosaur’s bones, but also at traces of skin and soft tissue that may have been unstable.These are destroyed or taken away during the excavation process.

Stephanie Drumheller, a vertebrate paleontologist at the University of Tennessee, says more mummies provide more information about how these creatures grew and survived.

“Every time we find one, there’s a wealth of information about these animals,” said Drumheller, who was not involved in the research.

These renderings, combined with what scientists already know from other fossils, paint a detailed picture of what the duck-billed dinosaur looked like from its head to its hooves.

According to the study, it has a crest down its neck and back, which breaks into a row of spines running down the tail. Its skin was covered with small, pebble-like scales, no larger than an average lizard.

And, as we now know, it was rough.

“This is a milestone,” Sereno said. “Now we really know this dinosaur.”