Sometimes play doesn’t need a formal request. In the picture below you can see Loulis asking for a game of tug of war from the caregiver in the human area of West playroom by sticking a hose out through the caging.
As we have mentioned in previous blog posts, using non-verbal behaviors like postural congruence and facial expressions can significantly improve the interactions and relationships between the chimpanzees and their caregivers. Additionally, humans using chimpanzee behaviors during interactions, whether it is serving a meal or playing a game, have been found to enhance the experience for both parties involved. Here Lisa, the caregiver, invites Tatu to play using a play bow to solicit the game.
To learn more about chimpanzee behaviors in general (or play behaviors specifically) check out the abstracts of theses of past graduate students from CHCI posted here as a good starting point.