Object social play in cougar kittens, Puma Concolor

Most researches on object play have been focused on the interaction of an individual and an object, saving less attention for social interactions occurring during such activity. We studied object-oriented social play in two captive Puma concolor sibling kittens (male and female) while they were 10-25 weeks. Both the duration of interactions and levels of cooperation decreased over the 25-week period (p=0.008 and p=0.018). Competition increased (p=0.03) showing a positive linear relationship with age (p=0.05). In the 10/19-week interval, kittens spent a long time in social interactions, sharing rather than competing for the object. Cooperation included pawing at and chasing the object together, while passing it to one another. Occasionally, one or the other kept running faster with the object, stimulating a contest. However, contests were settled peacefully and object play sequences terminated because of waning of interest. At 22 weeks, object social play became more competitive and its termination was mostly due to aggression. At 25 weeks, the male maintained 100% object possession, through serious aggression, as threat, challenge and vocalizations while starring at the female, which in turn showed off defensive postures and tried to withdraw from the context, avoiding physical attacks. In conclusion, object social play was either cooperative or competitive, shifting to aggression as kittens aged. At 25 weeks, social object play was absent and male possessive aggression occurred, reflecting similar levels of motivation over food resources. As it was the larger sibling, sex and body size might be critical factors promoting the evolution of male behaviour in the oldest age observed.