Dinosaurs thrived until asteroid hit, new fossils suggest.

The article discusses research, led by paleontologist Robert DePalma and presented at the 2021 meeting of the Geological Society of America, that suggests dinosaurs were witnesses to the asteroid that ushered them out of extinction. DePalma and his colleagues found evidence at a fossil-rich site in North Dakota called Tanis. Many paleontologists were skeptical, but geophysicist Sean Gulick believes the study shows a healthy ecosystem in the Dinosauria prior to the extinction.