However, fossil information from that time in other regions is much thinner, and it is not known whether the pattern seen in North America represents global dinosaur diversity. and then.
Egg fragments and eggshell represent the last two million years of the age of the dinosaurs, with fossils accounting for every 100,000 years. The study included obtaining detailed age estimates for rock layers by analyzing and applying computer modeling on more than 5500 geological samples.
analysis found Full Eggs and eggshell fragments from There were only three types of dinosaurs, the researchers said, indicating a decline in dinosaur biodiversity during that time period.
Macroolithus yaotunensis and Elongatoolithus elongatus belong to a group of toothless dinosaurs known as oviraptors, while the third belongs to, Stromatoolithus was pinglingensis A plant-eating hadrosaur, or a member of the duck-billed dinosaur group.
Researchers They said their find from fossilized eggs was consistent with fossilized dinosaur bones found in the same and surrounding area, although they did discover some additional dinosaur bones from the area showing Tyrannosaurus and sauropods also lived in the area between 66.4 million and 68.2 million years ago.
“Our results support a long-term decline in the world’s dinosaur biodiversity 66 million years ago, likely paving the way for the mass extinction of non-Cretaceous dinosaurs,” the study said.
Most of the dinosaurs became extinct, but Some of the smaller birds survived and evolved into the birds we see today.
“These findings also go against what appears from the egg remains and the diversity of bones, teeth and other remains found in places like Spain, (and) what we know based on the North American record,” he said by email. “So I think these authors are misinterpreting these signals.”
Still convinced that the asteroid strike was the real motive from the extinction of the dinosaurs.
“Maybe the dinosaurs were good and varied, and if the Cretaceous asteroid (they) weren’t after all, they might be the ones in control today as far as we know.”