This Stingray Chews Its Food

Stingrays from the Amazon River chew up their insect meals, just as mammals might, using complex jaw motions to shred the tough outer shells of juvenile beetles and dragonflies, researchers have found. This finding could shed light on the evolution of chewing, a behavior thought to have helped mammals take advantage of new diets when these animals diversified after the end of the age of dinosaurs, about 65 million years ago. In fact, for a very long time, scientists thought that only mammals pra