Dinosaurs Thrived in North America Before Asteroid Extinction

New research analyzing fossils from the Kirtland Formation in northern New Mexico indicates that dinosaur populations were thriving in North America up to about 400,000 years before the asteroid impact 66 million years ago that caused their mass extinction. The study, published in the journal Science, reveals distinct and diverse dinosaur communities including species like Tyrannosaurus rex and Triceratops-like herbivores, challenging previous ideas that dinosaurs were in decline prior to the impact. The dating of the fossils was confirmed through volcanic glass particles and magnetic mineral alignment in the surrounding rocks, situating these species close to the end of the Cretaceous period. However, scientists caution that this evidence from a single location may not represent global dinosaur diversity and that more data from other regions are needed to fully understand the global picture. Experts emphasize that while the findings are exciting and suggest dinosaurs were not already in decline, the overall extinction event likely involved complex ecological factors beyond just the asteroid impact. This research contributes important local evidence to the ongoing debate about dinosaur extinction dynamics before the catastrophic event.