Differences in play can illuminate differences in affiliation: A comparative study on chimpanzees and gorillas

Abstract

Play behaviour reinforces social affiliation in several primate species, including humans. Via a comparative approach, we tested the hypothesis that play dynamics in a group of lowland gorillas (Gorilla gorilla gorilla) are different from those in a group of chimpanzees (Pan troglodytes) as a reflection of their difference in social affiliation and agonistic support. We selected one group of lowland gorillas and one of chimpanzees, hosted at the ZooParc de Beauval (France), managed in a similar way and living in similar enclosures. The same observers video-collected and analysed data on play behaviour in both groups, by applying identical methodological procedures. Data showed that adult play was less frequent in the group of gorillas compare to chimpanzees. Polyadic play, which involves more than two players and is characterised by the most uncertain outcome, was also less frequent in gorillas than chimpanzees. Play sessions were more unbalanced (more unidirectional patterns by one of the player towards the other) in chimpanzees than in gorillas but in the latter play escalated more frequently into serious aggression. Play asymmetry in the gorilla group increased as the number of players increased, which explains why gorillas limited their polyadic playful interactions. In conclusion, our findings on the study groups of apes can be a valuable starting point to expand the study of social play in the great apes to evaluate if inter-individual affiliative relationships really account for the differences in play distribution and dynamics.

Facial mimicry and play: A comparative study in chimpanzees and gorillas.

“…Despite these similarities, the two study species show marked differences in their social structure and levels of inter-individual bonding (Cordoni, Norscia, Bobbio, & Palagi, 2018).…”

The neuroethology of spontaneous mimicry and emotional contagion in human and non-human animals

“…It is possible that chimpanzees perform DFM to re-affirm their playful intention at a later stage of the interaction, to prolong the positive social contact and favour social cohesion (Palagi et al, 2018a). A further explanation for the presence of the delayed response in chimpanzees (DFM) may be a possible audience effect on response elicitation, with this effect prevailing in chimpanzees due to their higher social cohesion compared to gorillas (Cordoni et al, 2018). The relation between yawn contagion and emotional contagion is under debate.…”

“…In chimpanzees and juvenile lowland gorillas, RFM is more frequent between strongly bonded subjects (Palagi et al, 2018a). It is difficult to assess the distribution of RFM in adult gorillas because play is not retained in adulthood (Cordoni et al, 2018).…”

Social play changes reflect differences in biology and development of three felids

“…Social play can help to establish hierarchy (Blumstein et al, 2013) and sibling aggression is supposed to evolve when competition is high and hierarchy is not established (Drummond, 2006). Play and aggression can act together in maintaining hierarchical relations (Paquette, 1994;Antonevich & Naidenko, 2008;Cordoni et al, 2018). One of the possible mechanisms is that low basic levels of play during a sensitive period could lead to difficulties in hierarchy establishment for lynx and thus favor the appearance of overt aggression.…”

“…after sibling aggression period in spotted hyaena Crocuta crocuta Erxleben, 1777 (Drea et al, 1996). Therefore, social play is supposed to facilitate social cohesion and to reduce aggression (West, 1974;Drea et al, 1996;Burghardt, 2005;Palagi et al, 2016aPalagi et al, , 2016bCordoni et al, 2018) but see also (Sharpe & Cherry, 2003;Sharpe, 2005). In regard to Eurasian lynx we expected that social play would increase after a period of social tension, after sibling aggression in lynx (the 'Cohesive play' hypothesis) but not in two other species.…”