Is Play Unique to Mammals?

Fun is in the beak of the beholder

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.

By that definition, the jungle is full of horseplay. Recreation is well documented in big-brained birds, such as crows and hawks, which chase each other and drop and catch objects seemingly for the hell of it. For other animals, the data is sketchier, often relying on just one case, but does suggest that play beyond birds and mammals is indeed possible. A Komodo dragon at the National Zoo in Washington, D.C., plays tug-of-war with its keepers, and soft-shelled turtles at other zoos push balls with their snouts and swim through hoops. Wild-reared octopi entertain themselves in the lab by towing toys or passing them between tentacles. Another study documents what seems to be wasps play-fighting.

"People have observed that wasps and fish can play," says Sergio Pellis, who studies animal behavior at the University of Lethbridge in Alberta. "We're finding out that play is not just for intelligent, big-brained animals."

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