Dinosaurs were in decline before the end

The death of the dinosaurs 66 million years ago was caused by the impact of a huge asteroid on the Earth. However, paleontologists have continued to debate whether they were already in decline or not before the impact. Scientists now show that they were already in decline for as much as ten million years before the final death blow.

source https://www.sciencedaily.com/releases/2021/06/210629130518.htm