Sure you play tug with your dog, but would a Komodo Dragon receive the same joy from that game? Can a turtle play ball and actually understand the fun?

Gordon Burghardt is researching those questions, and he's found that play must match the following criteria: "Play is repeated behavior that is incompletely functional in the context or at the age in which it is performed and is initiated voluntarily when the animal or person is in a relaxed or low-stress setting.”

He describes his first encounter with Pigface, a Nile Soft-shell Turtle at the National Zoo in his recent article called "Recess" in The Scientist:

“It was by itself,” recalls Burghardt, currently at the University of Tennessee in Knoxville, and “it had started to knock around” a basketball provided by its keepers. The year was 1994, and play had only rarely and anecdotally been reported in animals other than mammals, but he thought that might be what Pigface was doing. The 1-meter-long turtle exuberantly pushed the ball around its aquatic enclosure, swimming through the water with ease as it batted the ball in front of it with its nose. “If you saw a dog or an otter going around batting a ball, bouncing around and chasing it, and going back and forth and doing it over and over again, we’d have no problem calling it play,” he says. “And that’s what the turtle was doing.”
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But despite this void in scientists’ understanding of the behavior, theories about why play exists abound. “Play is intriguing to me because it takes in so many other aspects of behavior. It’s a big mystery,” says Lewis. Although it may be hard to define, “when you see it, you think, ‘What is it, if it’s not play?’ They’re not feeding themselves, they’re not trying to get a mate, they’re not searching for shelter. They’re playing.”

The one key seen in all non-mammals is security. In the wild, reptiles particularly are engaged in avoiding predation, thermoregulating and outright survival leaving less time for fun antics. What we are seeing in captive reptiles is the ability to play. An amazing video is after the bump, showing various acts of play. Be sure to check out the full article to learn how octopi and even wasps play.