1:44:12The 250-million year rise and fall of the dinosaurs | Steve Brusatte
Paleontologist Steve Brusatte walks the entire 250 million year arc of the dinosaurs, and his framing is that everyone knows how they died and almost nobody knows why they lived. The story starts with the end-Permian extinction that killed 90 to 95 percent of species, runs through 30 million years of dinosaurs as second rate characters underneath car sized amphibians and a menagerie of crocodile relatives, and turns on a second extinction at the end of the Triassic that erased the competition for reasons nobody can explain. From there: the Jurassic giants, the middle Cretaceous turnover the fossil record barely captures, T. rex as the last act of a hundred million year lineage that spent most of it person sized, and the Chicxulub impact in the detail the evidence actually supports. The last two chapters argue that the mammal story is the same story, with bodies racing ahead of brains after the asteroid, and that flight was an accident assembled from bipedality, feathers and display wings that all evolved in dinosaurs for other reasons.