Table 1.

Ethogram of play behaviors.

Behavior	Description
Rough-and tumble play	Any single display or combination of wrestling, biting, hitting, kicking, scratching, or pinning another animal in a non-agonistic context
Complete play initiation	Approach another animal and begin rough-and-tumble play
Attempted play initiation	Approach another animal and attempt to initiate rough-and-tumble play bout in the absence of a receive play by the target animal; includes chasing
Initiate play	Sum of complete play initiations and attempted play initiation
Receive play	Engage in play with another animal that has initiated a play bout
Overall play	Summation of complete play initiations and receive play behavior (does not include attempted play initiations)