Expert: Walter Hintz - 11/8/2006

Question
I know that mammals are the only species that play, and that mammilian play in the animal world usually serves to perfect skills necessary to cope with adult responsibility.
My question is: How is this reprented in the human world?

Answer
Hi Cornell
When you get right down to it play is merely practice for something the animal has to do later in life.  But when is it really "play".  Does the animal seem to be having fun with the play.  If you watch kittens and puppies wrestling around with each other and biting each other in mock fights. They seem to be having fun but they are practicing for carnivorous activity that they will use later on. Baby sea lions constantly fight with each other. While snorkeling with sea lions in the Galapagos Islands I came upon one with a stick in its mouth.  It would come close tempting me to grab the stick and when I reached for it the animal would swim away and then come back just like a dog does.  It seemed to be having fun. Perhaps it was practicing escape skills.
 Incidentally some birds also exhibit play behavior.  I watched red footed boobies in the Galapagos Islands tossing sticks up in the air and trying to catch them.  Why? They swallow fish whole and when they dive and catch one they toss it into the air so they can swallow it head first.  Swallowing it tail first could result in the spines sticking in their throat.
Finally I get to your question. Except for the large brain humans are just like any other mammal. All those children cavorting on the playground are practicing for things they will have to do later in life.  Catching a ball is a way of not letting it hit you in the face.