Sign up for CNN’s Wonder Theory newsletter. Explore the universe with news of amazing discoveries, scientific advances and more.
CNN
–
The skin of a 67 million-year-old dinosaur revealed bites and wounds from an ancient crocodile, and how its flesh ripped apart may explain why it was mummified.
Skin degrades much more easily than bones, so it is very rare to find fossilized dinosaur skin.
New research on the 7-meter (23-foot) Edmontosaurus, a plant-eating hadrosaur found near the town of Marmarth, North Dakota, in 1999 sheds light on the factors that have allowed the skin to survive through the eons.
“The bite marks were really unexpected. It was thought that the soft tissues wouldn’t preserve if they were damaged before burial, so the damage done by the carnivores is what really got us thinking about how these fossils formed in the first place,” University of Tennessee Department of Earth and Planetary Sciences , is a co-author of the new study.
Paleontologists used to think that a dinosaur, or any prehistoric creature, needed to be buried very quickly to preserve soft tissue – but that wasn’t the case for this poor hadrosaurus.
Researchers think the bite marks on the hadrosaur’s arm came from an ancient crocodile relative, but they aren’t sure what type of animal scratched its tail or squeaked — although it was likely larger. It is not clear whether the injuries to his arm and tail killed him or whether they were caused by scavengers after his death.
However, Drumheller-Horton explained, it was the misfortune of the dinosaurs that allowed his skin to preserve.
“To try and put it in as little disgust as possible — puncturing the skin allowed the gases and fluids associated with subsequent decomposition to escape. That hollow skin was left behind to dry. Naturally mummified skin like this could last for weeks to months even in somewhat humid environments, and the more The longer it lasts, the more likely it will be buried and petrified.
The bluish color of the fossilized skin is not thought to reflect what it would have been like when the dinosaur was alive. However, the high iron content in the rocks during the fossilization process may have affected them.
While it is often depicted as a greenish-gray, the color of most dinosaurs is largely unknown. Studies on fossils Dinosaur feathers revealed that some were surprisingly colorful.
However, the hadrosaur’s skin provided a lot of information about the size and patterns of scales across the dinosaur’s body as well as how much muscle mass it had – based on how extensive the skin was in that area.
“Skin breaks down much more easily than bone, so different and less common processes are required to preserve the skin long enough to be buried and fossilized,” said research co-author Clint Boyd, chief paleontologist with the North Dakota Geological Survey.
He said there may have been fewer than 20 real dinosaur “mummy”, with complete or nearly complete sets of soft-tissue remains.
“To put it in context, I’ve found thousands of fossils in my career, but only one of those preserved skin impressions (a fingerprint of the skin, not the preserved skin itself) and never myself have I found one that has the skin,” Boyd said via email.
The search was published in PLOS One magazine on Wednesday.