1. Ask first and communicate clearly. Many nonhumans announce that they want to play and not fight or mate. Canids punctuate play sequences using a bow to solicit play, crouching on their forelimbs while standing on their hind legs. Bows are used almost exclusively during play and are highly stereotyped — that is, they always look the same — so the message “Come play with me” or “I still want to play” is clear. Play bows are honest signals, a sign of trust.
Even when an individual follows a play bow with seemingly aggressive actions such as baring teeth, growling or biting, their companions demonstrate submission or avoidance only around 15% of the time, which suggests they trust the bow’s message that whatever follows is meant in fun. Trust in one another’s honest communication is vital for fair play and a smoothly functioning social group.2. Mind your manners. Animals consider their play partners’ abilities and engage in self-handicapping and role reversing to create and maintain equal footing. For instance, a coyote might not bite their play partner as hard as they can, handicapping themselves to keep things fair. And a dominant pack member might perform a role reversal, rolling over on their back (a sign of submission that they would never offer during real aggression) to let their lower-status play partner take a turn at “winning.”
Human children also behave this way when they play, for instance, taking turns overpowering each other in a mock wrestling match. By keeping things fair in this manner, every member of the group can play with every other member, building bonds that keep the group cohesive and strong.
3. Admit when you are wrong. Even when everyone wants to keep things fair, play can sometimes get out of hand. When an animal misbehaves or accidentally hurts his play partner, they typically apologize, just like a human would. After an intense bite, a bow sends the message, “Sorry I bit you so hard — this is still play regardless of what I just did. Don’t leave; I’ll play fair.” For play to continue, the other individual must forgive the wrongdoing. And forgiveness is almost always offered; understanding and tolerance are abundant during play as well as in daily pack life.
4. Be honest. An apology, like an invitation to play, must be sincere. Individuals who continue to play unfairly or send dishonest signals often quickly find themselves ostracized. This has far greater consequences than simply reduced playtime. For example, my long-term field research shows that juvenile coyotes who do not play fair often end up leaving their pack and are up to four times more likely to die than those individuals who remain with others. There are substantial risks associated with dispersal by young coyotes, and violating social norms, established during play, is not good for perpetuating one’s genes.
[...]
A few people have asked me if dogs always play fair, mentioning a few examples in which play escalated into an encounter that seemed to be aggressive or it seemed like this was going to happen. I explain that this is extremely rare, and tell them about a study by Melissa Shyan and her colleagues in which it was reported that fewer than 0.5 percent of play fights in dogs developed into conflict, and only half of these were clearly aggressive encounters.
