We have been videotaping dog-dog play for more than 10 years and, together with our colleagues, have analyzed hundreds of hours of data to test hypotheses about play. We present our results at animal behavior conferences and publish in scientific journals. Here, we focus primarily on dog play that some might consider “inappropriate” or “not safe.”
In the field of animal behavior, researchers often refer to social play as “play fighting” because it includes many of the behaviors seen during real fights. For example, during play, one dog might chase and tackle another, or use a neck bite to force a partner to the ground. Dogs will also hip check or slam, mount, rear up, bite, stand over, sit on, bark, snarl, growl, bare their teeth and do chin-overs (i.e., place the underside of their chin over the neck of their partner). However, despite the overlap in behaviors, some clear differences exist between play fighting and real fighting. When playing, dogs inhibit the force of their bites and sometimes voluntarily give their partner a competitive advantage (self-handicap) by, for example, rolling on their backs or letting themselves be caught during a chase — behaviors that would never happen during real fighting.
In addition to inhibited bites and selfhandicapping, dogs clearly demarcate play by employing signals, such as play bows (i.e., putting the front half of the body on the ground while keeping the rear half up in the air) and exaggerated, bouncy movements. Anthropologist Gregory Bateson called play signals meta-communication, meaning communication about communication. Humans employ meta-communication a lot. For example, when teasing a friend, we may smile or use a certain tone of voice to indicate that we’re just kidding. Similarly, dogs play bow to invite play and to convey playful intentions during play. Marc Bekoff, while at the University of Colorado, did a study1 showing that dogs are most likely to play bow just before or immediately after performing an especially assertive behavior, such as a bite accompanied by a head shake. This pattern suggests that playing dogs recognize moments when their behavior can be misinterpreted as serious aggression and compensate by reminding their partner, “I’m still playing.”
By using meta-communication, social beings can step through a looking glass into a world that operates by different rules. Meta-communication allows humans and dogs to pretend — that is, to perform actions that appear to be one thing but actually mean something completely different. To people unfamiliar with the notion that some nonhuman animals have this ability, play that includes archetypal aggressive behaviors, like snarling and growling, can be quite confusing. Close attention to the context, however, can help us differentiate between play aggression and real aggression.
Even though play fighting is very different from real fighting, people often feel the need to intervene. Sometimes it is obvious at the beginning of a bout that two dogs are playing, but once the dogs start growling or their arousal intensifies, observers may no longer be sure that the dogs are still playing. After all, humans instinctively avoid a dog who is snarling or baring his teeth, and it is natural to think that our dogs should do the same. When people interrupt really rowdy play, they assume that they are “playing it safe,” that is, doing no harm. But what if this assumption is mistaken?
Our research shows that for many dogs, play fighting is the primary method used to negotiate new relationships and develop lasting friendships. Although play is fun, it also offers serious opportunities to communicate with another dog. In this sense, play is a kind of language. Thus, when we regularly break up what we consider “inappropriate” play, are we doing our dogs a service, or confusing them by constantly butting into their private conversations? Most importantly, how can we tell the difference?