Why animals love to play

It's playtime! A leopard cub romps with its mother and swats her on the nose. A young mountain goat leaps and twists in the air. In a blur of fur, wolves chase each other through the snow. A rhesus monkey executes a perfect backflip. A parrot stands on its head. Wings spread, legs extended, two Eurasian cranes leap into the air together like ballet dancers. A garden warbler perched on a branch makes clinking sounds by dropping stones into a glass container on the ground. Young Adelie penguins knock each other off blocks of ice, then climb back up to do it again and again.

Play is a puzzle to scientists. Why do animals spend time and energy doing such silly things that seem to have no purpose? The struggle for survival in nature is deadly serious. What place is there for activities that don't help animals eat, grow, and reproduce?

And play is risky. Animals can break bones, pull muscles, or get bitten too hard. In a study of 14 Siberian ibexes (wild goats), more than one-third were hurt badly enough during play to cause limps-a serious concern in the race for survival. And animals can become so wrapped up in play that they are unaware of danger. One study showed that 80 percent of the deaths among young fur seals occurred because the playing pups didn't see predators coming!

Why is play worth the risk? Many scientists believe it's essential for survival-as important as food or sleep. According to animal play expert Marc Bekoff of the University of Colorado, "play is serious business."

Getting Ready for the Adult World

Most scientists believe that when animals play, they are practicing skills they'll need later in life. This is why different kinds of animals play in different ways. Young predators, such as wolves, lions, and bears, play by stalking, pouncing, biting, and shaking their heads from side to side. They're honing their skills for when they will run down, catch, and kill prey. When a wolf pup chases its own tail, bites it, and yanks it back and forth, the pup is rehearsing skills it'll need one day as a hunter.

Prey animals, such as elk, deer, or antelope, play differently. They dash about erratically, leaping wildly in the air-twisting, turning, and twirling. According to biologist John Byers of the University of Idaho, they act like they have "flies in their brains." But these animals are rehearsing skills they'll need one day to escape predators and avoid becoming dinner.

In many species, males and females play differently, depending upon what their adult roles will be. Generally, but not always, males tend to be more aggressive than females. Boy mountain goats play rougher than girl mountain goats. The boys charge each other and butt heads-practicing for when they will fight for mates as adults.

Young female Japanese macaques (a kind of monkey) spend most of their time playing gently and grooming playmates-skills they'll need as mothers. Male macaques prefer to wrestle, tumble, leap from high branches, and chase each other-getting ready for the time when they'll need to defend and protect the group.

With spotted hyenas, it's a different story. Adult females are bigger, stronger, and more aggressive than adult males. It's the females' job to protect and defend the pack. It's not surprising, then, that girl spotted hyenas "play-fight" more than the boys.

Dangerous Play

Besides preparing for their specific adult roles, animals at play may be "training for the unexpected," as Marc Bekoff puts it. In play, animals learn about the world around them and their own physical limits. The need to test those limits, and experience unpredictable situations, could explain why animals sometimes seem to enjoy play that is somewhat dangerous.

A study of Siberian ibexes at Brookfield Zoo near Chicago showed that even though half their enclosure was flat and grassy-a perfect place to frolic in safety-the young goats chose to play most of the time on a steep, rocky area where they were much more likely to get hurt. Why did they place themselves in danger?

Bekoff believes that such play helps animals develop flexibility-in their minds as well as their muscles-so that they are better prepared to deal with unexpected or uncontrolled events. In the confusion of fleeing a sudden attack by a predator, an ibex may stumble or crash into another member of the herd. But if it has had experience regaining its footing in play, its misstep is less likely to spell disaster.

Keeping It Fun

Through play, animals learn how to communicate with others of their species and get along with members of their group. And that can be a matter of life and death. Young coyotes spend only about one to two percent of their time playing. But if they fail to play and bond with others, they tend to leave the pack. About 60 percent of coyote pups that leave their social group die.

But how do animals find playmates? Animals can't say, "Can Scruffy come out for a game of tag?" They have other ways of inviting play.

Members of the dog family, such as wolves, coyotes, foxes, and jackals, use a play bow. They crouch down on their forelimbs, stick their rear ends in the air, wag their tails, and bark. Bears, too, perform similar bows.

Cats, dogs, and bears also invite play with exaggerated paw movements. They touch or slap their intended play partner in a relaxed way. Cats usually keep their claws retracted; bears angle their claws to do no harm.

A rapid approach and withdrawal is an invitation to chase; so is a fake-left-go-right maneuver. Relaxed and loose-limbed, an animal taking a gamboling approach looks like its body is held together with rubber bands. In animal "talk" that practically shouts, "Come play with me!"

During play, animals constantly monitor their behavior to keep play going. If one animal plays too rough, the play ends. To keep things "fun," they often reverse roles. A stronger or dominant animal will lie on its back, assuming a submissive position, while a weaker animal gets to play "boss."

Tiguak and Eddy

Blind and deaf at birth-weighing only about one and a half pounds-polar bears spend their first month nursing and sleeping. When they're a little older, their mothers teach them how to play. But Tiguak, a little polar bear at Chicago's Brookfield Zoo, was abandoned by her mother a few days after she was born. Zookeepers knew that if Tiguak didn't learn to play and bond with other polar bears, she'd never have a family of her own. But how do you teach a one-year-old, 300-pound bear to play? Get her a one-year-old, 300-pound friend!

Eddy, a "fun-loving" polar bear from the Jardin Zoo in Quebec, Canada, seemed like the perfect playmate for Tiguak. Raised by his mother, he knew how to play. So zookeepers brought the two together.

At first, Tiguak and Eddy lived in separate, side-by-side caves. They switched living areas every week to get used to each other's scent. When they finally met face-to-face, two months later, Eddy was ready to romp. But Tiguak ignored him. He offered her toys-a ball, a Frisbee, a pail. She wasn't interested.

Zookeepers worried, but Eddy didn't give up. He invited her to join him with a play bow. Tiguak didn't know what it meant. Finally, he engaged her in a game of chase by running up to her, then running away. She raced after him, and they've been playing together ever since. When the time came for Eddy to go home, his bear-y best friend, Tiguak, went with him.

Playing animals bite, swat, and hip-slam one another, but not as hard as they can. Play may be rough and tumble, but the goal is not to get hurt or to hurt a play partner. Animals don't play to win. They just play.

Is Play "Brain Food"?

Research shows that smarter animals spend more time playing. Elephants play more than horses. Chimps play more than macaques. Wolves play more than rabbits. And parrots play more than either ducks or sparrows. Smarter animals also play in more creative and complex ways. Not surprisingly, humans and chimpanzees are among the most playful species.

Could play actually help the brain grow? Some scientists think so. They believe that play exercises the brain like lifting a weight exercises a muscle. They even call play "brain food."

John Byers studied brain size and playfulness in marsu- pials-animals like kangaroos, koalas, and wombats that carry their young in a pouch. He wondered if marsupials that played were brainier than those that did not. In Australia he observed head-butting wombats (which looked like "frolicking fire hydrants"), boxing kangaroos, and wrestling Tasmanian devils. He believed that they were not only having fun but were helping to wire their brains as well.

How could playing grow the brain? As Byers explains it, there's an overproduction of connections between nerve cells in the brain after birth. If these "extra" connections are not used, they disappear. Playing animals use many connections and so establish new pathways in the brain. The brain, in a way, is remodeled as the animal grows.

In the end, Byers discovered that when it comes to marsupial brain size, "if you snooze, you lose." Koalas sleep up to 20 hours a day. They played the least and had the smallest brains (compared to their body size). The frolicking wombats played the most and had the biggest brains.

Do Animals Play Fair?

All play is based on trust and requires cooperation. Marc Bekoff says, "Cheaters are not tolerated in play. If an animal cheats a lot, he'll have trouble getting other animals to play with him." Animal play has rules. When one animal invites another to play-and the other agrees-they're making a pact that says: "If you'll play with me, I'll play with you. I won't hurt you. I won't bite you around your eyes. I won't body-slam you too hard. I won't try to dominate you." Play signals are clear. If an animal breaks that pact, he'll have trouble finding playmates. Because play is so important, an animal that doesn't get to play may not survive.

Most behavior experts believe that only humans have a sense of right and wrong. But Bekoff disagrees. He believes that animals practice "wild justice," and that playing by the rules makes them more fit in the struggle for survival. "I'm starting to find evidence that a well-developed sense of fair play helps nonhuman animals live longer, more successful lives," Bekoff says. "Virtue is its own reward-fairer is fitter."

Copyright Carus Publishing Company Nov/Dec 2003
Provided by ProQuest Information and Learning Company. All rights Reserved