New Research on Dinosaur Populations Before Asteroid Impact
There’s been an ongoing debate over whether dinosaurs were in decline prior to the asteroid strike that occurred 66 million years ago, which is widely known to have caused a mass extinction event.
Recent findings indicate that dinosaur populations in North America were actually thriving just before the asteroid hit. However, experts outside the study caution that this may not capture the entire global situation.
“Dinosaurs exhibited a high degree of diversity, and it seems there were various distinct communities existing before their abrupt extinction,” noted Daniel Peppe, a paleontologist at Baylor University and co-author of the study.
The research stems from an analysis of part of the Kirtland Formation in northern New Mexico, a site known for its intriguing dinosaur fossils for nearly a century.
Scientists now assert that the fossils and the surrounding sediment are about 400,000 years older than the asteroid impact, a relatively brief span in geological terms. This age estimate was established through the study of volcanic glass particles in the sandstone and the magnetic orientation of minerals in the mudstone.
According to Peppe, “the animals found here must have lived toward the end of the Cretaceous period, the final age of the dinosaurs.”
This research was published recently in Science magazine.
The variety of dinosaur species identified in New Mexico compared to those found in Montana, which had previously been dated to a similar era, challenges the notion that dinosaurs were declining, he explained.
Fossils discovered at the New Mexico site include a Tyrannosaurus rex, a large long-necked dinosaur, and a horned herbivore akin to a Triceratops.
Experts not affiliated with the study reminded that findings from one location might not reflect wider trends. Mike Benton, a paleontologist from the University of Bristol, expressed enthusiasm for the new discoveries, but also emphasized that this is just one location and does not encapsulate the complexity of dinosaur life in North America or globally during that time.
Researchers have uncovered dinosaur fossils on all continents, but accurately dating them can often pose challenges, remarked Andrew Flynn, a paleontologist and study co-author from New Mexico State University.
Because easily dateable materials like carbon don’t persist in fossils, scientists typically have to rely on surrounding rocks with specific characteristics to establish their age.
Future research could provide deeper insights into the variety of dinosaur species that were alive globally right before the asteroid impact, Flynn suggested.
