mammals

Question submitted by Ward Danekas of Franklin Grove, Ill.

The answer appears to be no. A bird will spend hours tossing a pebble in the air, but it's nearly impossible to discern if it's goofing around or honing its talon-eye coordination. Gordon Burghardt, an expert on animal behavior at the University of Tennessee, defines play as behavior that doesn't seem to have a survival purpose, is rewarding in and of itself, and is performed when an animal is fully fed and stress-free.