Share it! Science : It's Play Time!


A playful brown bear? (source)

Do animals play? What exactly is play in the scientific sense? Well, if you have a pet you probably think the first question is a no brainer. Of course they do! The second question is not quite as easy to answer. In the past, scientists who studied animal behavior were hesitant to label behaviors as play because it would seem like anthropomorphism (or related human characteristics to animals). I do recall the professor of my Animal Behavior class in college repeatedly warning us against describing behaviors this way. This way of thinking is becoming more and more outdated in the animal behavior world. Scientists now are more comfortable with describing a behavior as "play" if it does not have a function or benefit. In other words, if it isn't something that has to do with finding food, survival or reproduction it might fall into the category of "play". Play has been observed in a wide range of animals from wasps to chimps.

A recent study observed a new play behavior in cichlid fish. Gordon Burghardt is a scientist who studies play in animals, amongst many other things. He heard about an interesting behavior observed by James Murphy a herpetologist at Smithsonian's National Zoological Park in Washington, D.C. Murphy observed a cichlid fish in his aquarium at home bumping into a weighted floating thermometer over and over again. The fish would strike it, then once it popped back up, it would hit it again. They filmed this fish and others in similar situations exhibiting this behavior again and again. The fish all did it, but had different methods of going about it. Was this play, or another behavior?

Cichlid Fish (source)

In order to find out, they tested to be sure they could rule out hunger, aggression and mating rituals. They found that the fish knocked the thermometer whether they had been fed or not, they were not showing aggression to other fish, and they were not exhibiting the full body vibrations that male cichlids do to attract a mate. The fish seemed to be using the thermometer as a punching bag because it was fun! The scientists published their results at the end of September in the journal Ethology.

No one is quite sure what the purpose or role for the cichlid play was. We can certainly see the role in other types of animal play, particularly when we see it in mammals. Play seems to strengthen social bonds, gives opportunities for young animals to practice adult behaviors like hunting and is an outlet for surplus energy. Animals play in groups, such as dogs at a dog park, or groups of young chimps. This is not surprising if we imagine a group of children together. They find all sorts of ways to play. Animals also play by themselves. An intriguing example of this is the observation that ravens "snowboard" down snowy rooftops in Alaska and Northern Canada. Ravens are known for their intelligence. After they slide down the snowy roof, they will head back up to the top and do it again. There seems to be no practical purpose for this behavior, therefore we can describe it as play.