Fossil may be from dino killed in asteroid strike
A small dinosaur leg discovered in southwestern North Dakota may have been ripped from the animal’s body on the same day a giant asteroid struck Earth and eventually wiped out the dinosaurs.
The team that found the specimen says the leg belonged to a plant-eating thescelosaurus. They also say the fossil, discovered with skin still attached, probably dates back 66 million years, when the extinction-level event occurred.
Also found were fish that breathed in impact debris once the planet was hit, a fossil turtle researchers say was pierced by a wooden stake, remains of small mammals and their burrows, skin from a horned triceratops, the embryo of a flying pterosaur inside its egg, and possibly a fragment from the asteroid.
The findings will air in a two-hour PBS special on May 11.
Robert DePalma, the University of Manchester graduate student leading the dig, said the project helped researchers fill in details about the day the asteroid struck Earth.
“It’s almost like watching it play out in the movies,” he told BBC News. “You look at the rock column, you look at the fossils there, and it brings you back to that day.”
Paul Barrett of London’s Natural History Museum isn’t affiliated with the project and told BBC News there are no signs of disease or bite marks on the leg.
“So, the best idea that we have is that this is an animal that died more or less instantaneously,” Barrett said.
Some experts are skeptical, however. Anthony Fiorillo, a research professor at Southern Methodist University in Texas, is an expert in taphonomy, a branch of paleontology focusing on how fossils form. He called the leg “beautifully preserved,” noting it’s intact with fossilized soft tissue, which is unusual on dinosaur fossils.
The team has an interesting story, but details are lacking, Fiorillo said.
“A corpse deteriorates, so it could be equally as viable that this animal had died and this leg, the tissue holding it in place, had deteriorated to the point where some kind of sedimentological event pulled it off the animal and buried it 100 feet away from where the rest of the corpse was,” Fiorillo said.
Liz Freedman Fowler, an assistant professor of biological and geological sciences at Dickinson State University in North Dakota, echoed Fiorillo’s concerns.
“You can’t really see much surface texture” on the fossil, she told USA TODAY. “There’s one little patch that looks like skin, but the rest of it the photos aren’t good enough to really say.”
Regarding the recent discovery, finding such an array of preserved fossils in the same place is unusual, Fowler said. She’s waiting for more evidence, like maps and 3D scans of the site.