Conflict management in wolves and dogs: domestication effect

Individuals living in group gain benefits by cooperating with each other but they also compete with others for resources. To continue to benefit from group-living, animals have developed a variety of peace-keeping tactics, including behavioural mechanisms that regulate resource distribution, prevent aggressive escalation of conflicts and mitigate or repair the damage caused by such escalations. It follows that mechanisms of conflict management are a critical component of the social life of any group-living species. Conflict resolution appears to be a natural phenomenon with similar expressions and procedures in different species. However, while several theories have been developed and tested in order to discuss how nonhuman primates manage aggressive conflicts, few efforts have been made to empirically test corresponding hypotheses in other highly social species. Such data from a wide range of taxa are a prerequisite, however, to develop a more comprehensive understanding of the social conditions under which conflict resolution occurs, the cognitive capacities required for it and the selective forces that have shaped its evolution. In this project, we aim at closing the gap by investigating conflict management in pack-living wolves (Canis lupus) and dogs (Canis familiaris). Since several studies suggest that both species show a social organization similar to those of some primate species, a number of hypotheses regarding the function of conflict management, that have so far been considered only in primates, will be tested (Question 1). Several authors suggest a co-variance between the use of socially complex strategies and socio-cognitive skills that enable group living. Current theories outline the possibility that the process of domestication has changed dogs` socio-cognitive skills when compared to those of their wolf ancestor so as to allow them to become better adapted to the human environment. However, it is unknown whether the change in cognitive abilities has also caused changes in the social relationships and conflict management skills of dogs when they interact with their conspecifics. Therefore, we aim to compare conflict management strategies between wolf and dog packs in order to shed light on the effect of domestication on such behavioural mechanisms and to highlight new questions about socio-cognitive skills of dogs. Overall, three opposing working hypotheses will be put forward to explain possible differences or similarities between captive wolf and domestic dog packs living under the same conditions (Question 2). The Wolf Science Center offers a unique opportunity to investigate the effects of domestication by comparing dog and wolf packs the members of which are raised and kept in the same way into adulthood. This approach ensures that the behavioural differences we find will be based on species-specific genetic differences, and cannot be attributed to differences in individual experiences.

All social groups benefit from cooperation between members, but conflicts arising from competition over resources may jeopardize future cooperation and compromise the benefits of sociality. Mechanisms for the prevention or resolution of conflicts are an essential component of group-living species. The anticipatory exchanges of friendly behaviour (pre-conflict management) may reduce aggressive competition between group members before a predictable period of conflict, whereas, post-conflict strategies including reconciliation and consolation may repair damage after the conflict has occurred. Reconciliation, (i.e. friendly interaction between opponents after a conflict), reduces the occurrence of further aggression and restores damaged relationships. Consolation (i.e. friendly interactions between the victim and abystander) alleviates stress in the victim. Conflict management strategies have been extensively studied in primates, but little is known about their use in other social species. We observed the social interactions of wolves and their domestic descendants, dogs, with the aim to understand these strategies and investigate the effect of the domestication process. Conflicts between wolves, though more frequent than in dogs, were characterised by less severe and more ritualized aggression. In wolf packs, we observed the use of both pre- and post-conflict strategies: we found that friendly interactions occurring before a predictable period of conflict (i.e. feeding) reduced the risk of aggressive escalation and increased co-feeding. Furthermore, reconciliations occurring shortly after a conflict reduced the occurrence of further aggression between opponents; finally, both reconciliation and consolation decreased the victims stress behaviours. In contrast to wolves, dogs did not use these pre- and post-conflict management strategies but instead, after a conflict, they avoided interacting and communicating with their opponents or other pack members. While the wolf results are in line with previous studies carried out in different environmental conditions, the dog results are in contrast with other studies showing that dogs may use conflict management strategies. This is the first set of studies, which directly compared the conflict management strategies of wolves and dogs. They advance our understanding of these processes in these two species and highlight the significant changes to intraspecific behaviour due to the domestication process. We conclude that in wolves, due to their high dependence on sociality and cooperation between pack members, the management of conflicts plays a key role in the maintenance of pack cohesiveness. Conversely, in dogs, which, as a consequence of domestication, rely on sociality and cooperation with other dogs less than wolves, the use of conflict management strategies may be highly influenced by social and environmental conditions. Future research should help to clarify which factors may promote and modulate the use of these strategies in domestic dogs.