Ancient fossils show how the last mass extinction forever scrambled the ocean’s biodiversity

Ancient fossils show how the last mass extinction forever scrambled the ocean’s biodiversity

By Stewart Edie, Smithsonian Institution About 66 million years ago – perhaps on a downright unlucky day in May – an asteroid smashed into our planet. The fallout was immediate and severe. Evidence shows that about 70% of species went extinct in a geological instant, and not just those famous dinosaurs that once stalked the land. Masters of the Mesozoic oceans were also wiped out, from mosasaurs – a group of aquatic reptiles topping the food cha…