A scene familiar to any dog owner: the dog suddenly folds its front legs, resting on its elbows, head level and eyes aimed up. The rear end, meanwhile has remained standing, as if it had a life of its own. Like the bark, this communication appears to combine juvenile submission with adult readiness to run. This gesture, common to dogs, wolves and coyotes, communicates play time. Called a bow, the body position may precede a sharp yip toward the human. But does bowing function in canine-to-canine communication? Marc Bekoff, of the University of Colorado, studied videotapes of adult dogs, domestic puppies, wolf pups and coyote pups, noting exactly what behavior followed and preceded each bow. He often saw a bow follow or precede move that could be interpreted as threatening, such as a bite. Bekoff concludes the bow acts not merely as a stereotyped “Let’s play” signal, but as a sort of body language punctuation, attaching the meaning “play” to other actions, and reassuring the playmate that the rules of rough and tumble haven’t changed.
Lion cubs play-fight as well, practicing pouncing and other skills they’ll need as adults. But even small cubs sport sharp claws and teeth, so they need to communicate that an attack is just for fun. Lion cubs tell their partners they’re still playing by walking in a stilted, exaggerated fashion and by keeping their claws sheathed during play attacks.