Giada Cordoni and Elisabetta Palagi

In canids, play dynamics seem to be more affected by dominance hierarchy rather than cooperative social bonds. To test this hypothesis we studied a colony of grey wolves (Canis lupus lupus). We quantified the dynamics of aggression and hierarchical changes in two periods (Sample 1 and Sample 2). Sample 2 was characterized by higher level of aggressiveness and by a more strict and steep linear hierarchy. The negative correlation between rank distance and play frequency characterizing both periods and the higher play asymmetry in Sample 2 suggest that rank rules dictate play rules thus highlighting the competitive side of wolf play behaviour. The overall affiliation rates showed no variation between the two samples. Yet, play performance was modified. In Sample 2, wolves reduced playful activity, limited the number of players per session and avoided playing during high competition contexts. Our findings support the hypothesis that wolf play is modulated by dominance relationships more than by cooperative social bonds.

Giada Cordoni, Elisa Demuru, Enrico Ceccarelli and Elisabetta Palagi

Play provides children with the opportunity to train in fundamental social skills, including conflict management. Here, we evaluate the management of play, aggressive conflict and reconciliation in 3- to 5-year-old preschool children. 3-year-old children show the highest levels of aggressive conflicts in free play, and do not reconcile their aggressive conflicts in the first months of the preschool year because they still lack social capacities to successfully manage interactions with peers. We found no gender bias in being aggressors or victims, but gender-typed traits were reflected in the expression of aggressiveness in same-sex peers for boys, who rely more on physical contacts than girls. Gender segregation in play is seen only in boys, regardless of age. Our results emphasize the importance of considering play, aggressive conflicts, and reconciliation as a whole, in order to obtain a comprehensive overview of the development of pre- and post-conflict dynamics in humans.

Elisabetta Palagi, Giada Cordoni, Elisa Demuru and Marc Bekoff

The concept of peace, with its corollary of behaviours, strategies and social implications, is commonly believed as a uniquely human feature. Through a comparative approach, we show how social play in animals may have paved the way for the emergence of peace. By playing fairly, human and nonhuman animals learn to manage their social dynamics in a more relaxed and tolerant way that results in a more effective management of conflicts. We show that play promotes tolerance, cooperation, fairness and reciprocity, which are essential elements of the so-called positive peace. This kind of peace is reached through an evolving process in which individuals continually modify social relationships to attain peaceful coexistence. In conclusion, we assume that the concept of peace has deep biological roots that constitute the basis for more sophisticated cultural constructions.