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A 67-million-year-old dinosaur skin has revealed bites and wounds from an ancient crocodile and how its flesh was torn away may explain why it became mummified.
Skin decays much more easily than bone, so finding fossilized dinosaur skin is extremely rare.
New research on a 7-meter (23-foot) long Edmontosaurus, a type of plant-eating hadrosaur found in 1999 near the town of Marmarth, North Dakota, sheds light on the skin that allowed it to survive through the ages.
“The bite marks were really unexpected. “It was thought that soft tissue wouldn’t preserve if it was damaged before burial, so the carnivore damage really started us thinking about how these fossils were made,” said Stephanie Drumheller-Horton, a paleontologist. of the University of Tennessee’s Department of Earth and Planetary Sciences, is an author of the new study.
Paleontologists used to think that a dinosaur or any prehistoric animal needed to be buried extremely quickly to preserve the soft tissue – but this was not the case with this poor hadrosaur.
The researchers think the bite marks on the hadrosaur’s arms came from an ancient relative of a crocodile, but they aren’t sure what kind of animal clawed or crushed its tail — though it was probably large. It is not clear whether he was killed due to injuries to his arms and tail or was mauled by scavengers after his death.
However, it was the dinosaur’s bad luck that allowed its skin to be preserved, Drumheller-Horton explained.
“To try to put it in the least disgusting way possible—perforating the skin allows the gases and fluids associated with later decomposition to escape. That leaves the hollow skin behind to dry out. Such naturally mummified skin can last weeks to months even in fairly humid environments. And the longer it lasts, the more likely it is to be buried and fossilized,” he said.
The blue color of fossilized skin is not thought to reflect what dinosaurs were like when they lived. However, the high iron content in the rock during the fossilization process can affect this.
Although often depicted as greenish gray, it is largely unknown what the color of most dinosaurs was. Studies on Fossils Dinosaur feathers revealed that some were surprisingly colorful.
Hadrosaur skin, however, provided much information about the size and pattern of scales across the dinosaur’s body, as well as the amount of muscle mass—based on how extensive the skin was in that area.
“Skin decomposes much more easily than bone, so it takes a different and less commonly observed process to preserve skin enough to be buried and fossilized,” said study co-author Clint Boyd, a senior paleontologist with the North Dakota Geological Survey.
He said there were probably fewer than 20 true dinosaur “mummies,” consisting of complete to nearly complete sets with soft tissue.
“For context, I’ve found thousands of fossils in my career, but only one of those skin impressions is preserved (the skin impression, not the actual preserved skin) and I’ve never found one that had skin. Reserved,” Boyd said via email.
The study was published in 2009 Thursday in the journal PLOS ONE.
