The fossil of a dinosaur thought to have been killed on the day of an asteroid strike has been discovered by British archaeologists.
Scientists working at the Tanis dig site in North Dakota, USA have discovered an almost perfectly preserved leg from a Thescelosaurus, complete with skin.
Those working at the site believe it was killed and entombed on the day of a giant asteroid strike 66 million years ago that brought about the end of the dinosaurs. That impact is believed to have taken place in the Gulf of Mexico, some 2,500 miles away from Tanis, but was still powerful enough to cause a surge of water that buried all those living in what is now the Upper Midwest state.
"It's a Thescelosaurus. It's from a group that we didn't have any previous record of what its skin looked like, and it shows very conclusively that these animals were very scaly, like lizards. They weren't feathered like their meat-eating contemporaries,” Prof Paul Barrett, a world-leading expert on herbivorous dinosaurs from London's Natural History Museum, told the BBC.
"This looks like an animal whose leg has simply been ripped off really quickly. There's no evidence on the leg of disease, there are no obvious pathologies, there's no trace of the leg being scavenged, such as bite marks or bits of it that are missing."
"So, the best idea that we have is that this is an animal that died more or less instantaneously."
If, as is believed, the fossil is from the day of the strike, it will represent a huge breakthrough for the scientific community. Exceedingly few fossils that can be dated to within even the final few thousand years before impact have ever been discovered.
"We've got so many details with this site that tell us what happened moment by moment, it's almost like watching it play out in the movies. You look at the rock column, you look at the fossils there, and it brings you back to that day," Robert DePalma, the University of Manchester graduate student who leads the Tanis dig, told the BBC.
Archaeologists also believe they have discovered the fossilised remains of fish that breathed in debris from the asteroid as it rained down from the sky.
A sturgeon and paddlefish found at Tanis reportedly have small particles of molten rock lodged in their gills that scientists hypothesise rained down into rivers after the asteroid made impact with Earth.
"Those fish with the spherules in their gills, they're an absolute calling card for the asteroid. But for some of the other claims - I'd say they have a lot of circumstantial evidence that hasn't yet been presented to the jury," Prof Barrett said.
- The findings from the Tanis dig site will be broadcast on April 15 in Dinosaurs: The Final Day with Sir David Attenborough (BBC One)
