However, this explanation was not satisfactory, Drumheller-Horton said, because an underground corpse could also be affected by insects, fungi, or even microorganisms. There had to be another reason for the mummified fossils to appear. Dakota now appears to have indications of an unexpected way that skin and nail keratin can survive.
“We often find dinosaur skin surprisingly in fossils,” Drumheller-Horton says. The way the Dakota has been preserved may provide an explanation.
dried dinosaur skin
Dakota wasn’t soon buried under the sand. According to Drumheller-Horton and colleagues, the corpse has been out in the open for more than 66 million years, and has dried out over several weeks or months. The scavengers did indeed peck the remains, as evidenced by bits of Dakota skin showing bite marks from carnivores gnawing at the corpse before it was finally buried.
“We know for sure that at least two carnivores, and possibly more, ate part of the leg and tail of the dead dinosaur,” Drumheller-Horton said. These opportunistic carnivores may have helped preserve the skin of the Dakota.
The bite marks indicate that the scavengers supposedly punched holes in the dinosaur’s body wall, allowing fluids, gases, and microbes from the decomposition to escape. While the inner tissues were eaten or decomposing, the scaly, scaly skin of the hadrosaur was allowed to dry in the sun, forming a kind of wrapping material around the bones before the animal was buried. Drumheller-Horton and her colleagues argue that this is why the Dakota appears to be “shrunk,” and that the skin has lost its original volume, but has shrunk to only a cortex of bone.
Paleontologists have puzzled over how dinosaur mummies were preserved for decades. Paleontologist Karen Ball of the New York Institute of Technology, who was not involved in the study, says the new study “provides strong evidence” that the Dakota was exposed to the elements before the remains were finally buried. While it is difficult to determine when the scavengers ate the remains, she says they were clearly rotten and somewhat dry, and that the fossil did not originate from an intact carcass.
And Dakota may not be the only one who has experienced this process. Paleontologists often find skin or skin traces on these dinosaurs, with no remains of other soft tissues, such as internal organs. This may indicate that hadrosaurs’ skin was so hard that it was not very attractive to carnivores and that it was more resistant to impacts than the softer parts of the dinosaur’s body. As a result, there was a greater chance that the fossil remains would survive from him.
From the first “hoofs”
Specimens like the Dakota could shed new light on our understanding of the emergence of dinosaurs. Often this is based solely on animal bones. Animals living today have all kinds of boneless structures, such as the trunks of elephants or turkeys. This means we wouldn’t know them if we only had animal fossils at our disposal. Dinosaurs also undoubtedly had bumps or body parts that could not be seen in their skeleton. These features can be discovered by discovering well-preserved animals such as the Dakota.
The Dakota’s front legs, in particular, have proven to be a surprise to paleontologists. Paleontologists have already discovered on the basis of the skeletons found it edmontosaurus Four fingers on each front leg. By discovering the hadrosaur mummies and residual footprints, they concluded that those toes were held together by a kind of “glove”, and that they formed a kind of single brace rather than several separate fingers.
The Dakota was found to provide more clarity about this structure. “The term ‘hoof’ spread on social media when images of the animal’s leg first appeared, and that term has stuck around ever since,” said another researcher, Clint Boyd. The hull is not like a horse’s hoof, because the hard outer layer does not extend to the bottom of the leg. However, it looks like a hoof, with a large nail on the middle fingers, which differs from the legs of most other reptiles.
“The animal’s ‘hand’ is a bit like a hoof with a smaller back finger on either side,” says Ball.
And perhaps Dakota is hiding more secrets. “It is often thought that only imprints of dinosaur skin remain,” Drumheller-Horton says. “But we in Dakota see that there really is a complexion, in three dimensions.” This means that not only the shape of the skin has been preserved, but the skin itself has also been preserved for more than 66 million years.
“Discoveries like the Dakota give us a great opportunity to step back and think about the assumptions we’ve made about the anatomy of these animals,” Paul said.
This article was originally published in English at nationalgeographic.com