It was a good year for dino hunters. The Top Ten are not numbered but #4 from the top is “Dinosaurs Weren’t in Decline When the Asteroid Hit:
If dinosaurs “ruled the Earth” for millions of years, why were they hit so hard by the mass extinction of 66 million years ago? Paleontologists have been puzzling over this question for decades, and, some have suggested, dinosaurs might have already been dying back by time the asteroid struck. But an increasing amount of evidence contracts that view, including a study published this year in Royal Society Open Science. The researchers looked at different evolutionary trees for what dinosaurs were around during the end of the Cretaceous to track whether dinosaurs were dying out, thriving or staying the same. After sifting through the data, the paleontologists didn’t find any sign that dinosaurs were declining before the asteroid strike. In fact, dinosaurs seemed perfectly capable of evolving new species. If the asteroid had missed, the Age of Dinosaurs would have continued for a very long time.Riley Black, “The Top Ten Dinosaur Discoveries of 2020” at Smithsonian Magazine
Here’s the open access paper arguing the case.
The thing that still puzzles many of us is, if dinosaurs weren’t in decline, why did they all die out?
Here’s one scenario of the asteroid hit that is said to have taken out 100% of dinos: