New analyses of giant fossilized megalodon teeth are helping scientists unravel the mystery of their extinction
Millions of years ago, giant sharks three times larger than today's great whites stalked the world's ocean. They're long gone now, but occasionally, someone walking on a beach spots an odd triangular shape in the sand. On closer inspection, they realize it's a fossilized tooth as large as a human hand, with sharp serrated edges. And they have to wonder: What was that beast eating?