Slow march to extinction and sudden asteroid impact doomed dinos
Neither a giant asteroid nor a gradual die out can take full blame for dinosaurs’ demise.
Rather, the culprit may be both, two new studies suggest.
Tens of millions of years before the asteroid delivered its killer blow some 66 million years ago, the number of dinosaur species had already begun to drop, researchers report online April 18 in the Proceedings of the National Academy of Sciences. But not all dino groups were in decline, including some maniraptoran dinosaurs, a different group of researchers suggests online April 21 in Current Biology.
At first glance, the two studies seem to conflict, but “they can coexist,” says paleontologist Michael Benton, who coauthored the PNAS paper. Both studies add to what has become an increasingly intricate picture of dinosaurs’ final days.