Dinosaurs died off quickly after an asteroid sent a wall of fire and destruction across North America, a new study claims.
Researchers studying fossils found in Montana and North Dakota say an asteroid hit 65 million years ago and almost immediately wiped out the giant reptiles that once ruled the earth.
“What we found suggests that the dinosaurs were thriving, that they were doing extremely well during that time,” said Peter M. Sheehan of the Milwaukee Public Museum, one of the study’s authors.
“The asteroid impact brought a sudden and very abrupt demise to the species,” Sheehan said.
The newly updated theory, explained in the just-published issue of the journal Geology, gives credence to paleontologists and other scientists who long believed the dinosaurs were killed off by an asteroid strike.
Scientists theorize that the asteroid would have been about six-miles wide – and it probably hit Earth somewhere around the Yucatan Peninsula in Mexico.
But there remain several other schools of thought about the dinosaurs’ disappearance.
Some scientists contend they were killed over a long period of time by slow changes in Earth’s climate or ecology – and that they were dying out when the asteroid hit.
But Sheehan says fossil evidence shows that a variety of dinosaurs thrived in North Dakota and Montana until the very end.
Still, a scientist who believes the dinosaurs died off slowly says the new study wasn’t broad enough.
William A. Clemens of the University of California at Berkeley said Sheehan overlooks the fact that many other forms of life survived the asteroid.
“Why did amphibians go through this period unaffected?” Clemens asked. “There was a variety of birds, and they go through this period unaffected.”