Why Animals Play

Anyone who has watched young dogs chase one another, or seen dolphins leap from the water for no obvious reason, knows that animals play. For scientists, however, play has long been something of a puzzle. It uses up valuable energy, it can easily lead to injury, and a playing animal may fail to notice an approaching predator. According to the cold logic of survival, such behavior really ought to be a waste of time. The very fact that play has survived across so many different species suggests that it must somehow （ 1 ） these obvious costs.

The most popular explanation is that play is, in effect, practice for adult life. Young predators that wrestle and chase one another are thought to be developing the very skills they will later need in order to hunt, while gentle play-fighting may teach animals exactly how hard they can bite without causing real harm to a companion. （ 2 ） this view, animals are not simply having fun; they are rehearsing, in a safe setting, for the serious business of survival, at a time when their mistakes still carry very little cost.

Yet this neat explanation does not fit every case. Play has been observed in animals that do not hunt at all, and even in some that seem to have no obvious skills to practice. Many researchers now believe that play also helps animals form social bonds and learn to cope calmly with the unexpected. （ 3 ） being mere practice for particular tasks, in other words, play may help to build flexible minds that are capable of handling a constantly changing world. Far from a waste, it may be one of nature's clever ways of preparing for surprise.