The Asteroid That Killed the Dinosaurs Also Jumbled Shark Evolution
More than 500 different shark species roam Earth's oceans: from zippy little cookie-cutter sharks, to the iconic great white, to nightmarish goblin sharks, to 25-foot-long, filter-feeding basking sharks. And it seems that the current equilibrium of shark species we see today arose after the Cretaceous-Paleogene mass"