Post-conflict Affiliative Interactions Research Articles

Post-conflict opponent affiliation reduces victim re-aggression in a family group of captive arctic wolves (Canis lupus arctos).

Post-conflict affiliative interactions have been widely investigated in primates but not extensively in other species. Using the Post Conflict-Matched Control (PC-MC) comparison method, this study investigated the patterns of post-conflict opponent affiliation (POA) of a captive family group of 19 arctic wolves (Canis lupus arctos), investigating the correlation with various factors. We found that POAs occurred mainly in the non-feeding context and more often when the victim was dominant and the aggressor subordinate. Furthermore, POAs were more likely to have been initiated by the victim than the aggressor. Victims’ stress related behaviours occurred more in PC than MC periods, and more after high vs. low intensity aggressions but they were not more likely to occur after conflicts between wolves with a stronger social bond and POAs did not reduce their rate of occurrence. Our results showed that re-aggression was twice less frequent when a friendly interaction occurred between the aggressor and the victim, and consistent with this, victims engaged in POAs more often than the aggressor. Overall, our results support the hypothesis that POAs in wolves may have been selected for as a mechanism to avoid conflict escalation, which could lead to social disruption and hence jeopardize cooperative activities. The high relatedness among individuals in the pack and the greater dependence of all members on cooperation in breeding and hunting may reduce the importance of ‘relationship quality’ as a mediating factor of POAs, although dominance relationships, which are directly linked to the risks of further conflicts, do play an important role.

Vocalizations during post-conflict affiliations from victims toward aggressors based on uncertainty in Japanese macaques.

We investigated the use of vocalizations called “grunts,” “girneys,” and “coos” accompanied by post-conflict affiliative interaction between former opponents (reconciliation) in Japanese macaques (Macaca fuscata). Although reconciliation functions to repair bonds, such interactions sometimes entail risks of receiving further aggression. Vocalizations can be used at a distance from the former opponent; thus, we predict that vocalizations are used particularly by victims of a conflict, and are frequently used in situations of uncertainty when it is difficult for them to estimate whether the former opponent will resume aggression. In addition, we predict that vocalizations are effective in preventing further aggression. To test these hypotheses, we conducted observations of post-conflict and matched-control situations in female Japanese macaques living in a free-ranging group. We found that former opponents tended to be attracted to each other within the first minute following a conflict, thus demonstrating reconciliation behavior. Vocalizations were more frequently used by the victims in post-conflict interactions than under control situations; however, this tendency was not found in aggressors. When affiliation with the former opponent occurred, victims were more likely to use vocalizations towards less familiar opponents. These findings suggest that Japanese macaques used vocalizations more often when interacting with less predictable former opponents. Victims were more likely to receive aggression from former aggressors when engaged in affiliations with them than under no such affiliations. No significant differences were found in the probability of the victims receiving aggression, regardless of whether they used vocalizations; thus, whether the victim benefits from using vocalizations in these contexts remains unclear. Japanese macaques form despotic societies and therefore, further aggression was inevitable, to some degree, after a conflict. The use of vocalizations by a victim was found to depend on the nature of their relationship with the aggressor; however, the effectiveness of this behavior requires further investigation.

Postconflict Affiliation Among Bystanders in a Captive Group of Japanese Macaques (Macaca fuscata)

Social animals benefit from group living. However, competition for limited resources may lead to agonistic conflicts. These conflicts can affect the behavior and the social relationships, not only of the individuals involved in the confrontation, but also of bystanders. The aim of this study was to describe postconflict affiliative interactions among bystanders (quadratic affiliation) in a captive group of Japanese macaques (Macaca fuscata) and test whether 1) after observing a conflict bystanders tend to interact with other bystanders, 2) conflicts increase bystanders’ rates of self-directed behaviors (SDBs), 3) postconflict rates of SDBs mediate affiliative interactions between bystanders, and 4) quadratic affiliation decreases rates of SDBs to baseline levels. We used the postconflict matched-control (PC-MC) method (5 min focal samples) to record bystanders’ behavior (156 PC-MC pairs from 15 subjects). Results show that bystanders’ rates of SDBs increased above baseline levels after conflicts. Bystanders responded to conflicts by increasing affiliation with other bystanders (mainly with close associates) but not with former combatants. After quadratic affiliation, rates of SDBs decreased to baseline levels. Together with previous findings, these results support the idea that quadratic affiliation is a tension reduction mechanism in less tolerant species.

Ravens Reconcile after Aggressive Conflicts with Valuable Partners

Reconciliation, a post-conflict affiliative interaction between former opponents, is an important mechanism for reducing the costs of aggressive conflict in primates and some other mammals as it may repair the opponents' relationship and reduce post-conflict distress. Opponents who share a valuable relationship are expected to be more likely to reconcile as for such partners the benefits of relationship repair should outweigh the risk of renewed aggression. In birds, however, post-conflict behavior has thus far been marked by an apparent absence of reconciliation, suggested to result either from differing avian and mammalian strategies or because birds may not share valuable relationships with partners with whom they engage in aggressive conflict. Here, we demonstrate the occurrence of reconciliation in a group of captive subadult ravens (Corvus corax) and show that it is more likely to occur after conflicts between partners who share a valuable relationship. Furthermore, former opponents were less likely to engage in renewed aggression following reconciliation, suggesting that reconciliation repairs damage caused to their relationship by the preceding conflict. Our findings suggest not only that primate-like valuable relationships exist outside the pair bond in birds, but that such partners may employ the same mechanisms in birds as in primates to ensure that the benefits afforded by their relationships are maintained even when conflicts of interest escalate into aggression. These results provide further support for a convergent evolution of social strategies in avian and mammalian species.

Post-conflict friendly reunion in a permanent group of horses (Equus caballus)

Gregarious animals living in permanent social groups experience intra-group competition. Conflicts over resources can escalate into costly aggression and, in some conditions, non-dispersive forms of conflict resolution may be favoured. Post-conflict friendly reunions, hence reconciliation, have been described in a variety of species. The aim of this study was to explore, for the first time, the occurrence of reconciliation in a group of domestic horses (Equus caballus) and learn more about strategies used to maintain group cohesion. The behaviour of seven horses living as permanent group in an enclosure for at least 2 years was observed by video for 108h from June to August 2007. We used a Post-Conflict/Matched Control method to assess the existence of reconciliation and third-party affiliation. Behaviours recorded Post-Conflict, or during Matched Control periods, were classified as affiliative based on previous descriptions of visual communication patterns in horses. The proportion of attracted pairs over total post-conflict situations was significantly greater than the proportion of dispersed pairs, both during dyadic interactions (p<0.001) and during triadic interactions (p=0.002). The results of the present study show that both dyadic reconciliation and third-party post-conflict affiliative interactions form important social mechanisms for managing post-conflict situations in horses.

Reconciliation, consolation and postconflict behavioral specificity in chimpanzees

Conflicts of interest arise regularly in the lives of all group-living animals and may escalate into aggressive conflicts. The costs of aggressive escalation can be reduced through peaceful postconflict interactions. This study investigated the postconflict behavior of 22 adult chimpanzees at Chester Zoo. The occurrence of reconciliation, i.e. the postconflict affiliative reunion between conflict opponents, and consolation, i.e. a postconflict affiliative interaction directed from a third party to the recipient of aggression, were demonstrated. Consolation was more likely to occur in the absence of reconciliation than after reconciliation, and reconciliation was more likely to occur in the absence of consolation than after consolation, supporting the hypothesis that consolation acts as a substitute for reconciliation when the latter fails to occur. Evidence for behavioral specificity, i.e. context-specific use of certain behaviors, was found for both reconciliation and consolation, which, along with high conciliatory tendencies, suggests an explicit style of postconflict behavior in the study subjects.

Stress reduction through consolation in chimpanzees.

Consolation, i.e., postconflict affiliative interaction directed from a third party to the recipient of aggression, is assumed to have a stress-alleviating function. This function, however, has never been demonstrated. This study shows that consolation in chimpanzees reduces behavioral measures of stress in recipients of aggression. Furthermore, consolation was more likely to occur in the absence of reconciliation, i.e., postconflict affiliative interaction between former opponents. Consolation therefore may act as an alternative to reconciliation when the latter does not occur. In the debate about empathy in great apes, evidence for the stress-alleviating function of consolation in chimpanzees provides support for the argument that consolation could be critical behavior. Consistent with the argument that relationship quality affects their empathic responses, we found that consolation was more likely between individuals with more valuable relationships. Chimpanzees may thus respond to distressed valuable partners by consoling them, thereby reducing their stress levels, especially in the absence of reconciliation.

Age effects and gender differences on post-conflict reconciliation in preschool children

[We studied conflict management and post-conflict affiliative interactions (reconciliation) in 3-to-6 year-old preschool children. We found development in reconciliatory proficiency with age for boys, but girls reconciled at similar levels throughout the age span. After peer conflict, 3-year-old boys were less likely to reconcile than same-aged girls, or as boys aged 4–6 years. Gender differences were not manifested in older same-age-groups (4–6-year olds). Younger boys (3–4-year olds) experienced higher reconciliation rates in conflicts with older boys (5–6-year olds) than in conflicts with same aged boys. We found no significant age or gender effects in distribution of reconciliatory repertoire or frequency of non-affiliative conflict management strategies (aggression and displacement activities, indicative of stress responses). However, 6-year-old children were more likely than younger children to mediate in conflicts in which they were not opponents, but had witnessed. Though not confirmed statistically, this phenomenon appeared more pronounced in girls than boys. Together, our results suggest that at 3 years of age, preschool children employ sophisticated behaviours to resolve conflicts, displaying remarkable receptiveness and responsiveness to reconciliatory behaviours exhibited by older opponents., We studied conflict management and post-conflict affiliative interactions (reconciliation) in 3-to-6 year-old preschool children. We found development in reconciliatory proficiency with age for boys, but girls reconciled at similar levels throughout the age span. After peer conflict, 3-year-old boys were less likely to reconcile than same-aged girls, or as boys aged 4–6 years. Gender differences were not manifested in older same-age-groups (4–6-year olds). Younger boys (3–4-year olds) experienced higher reconciliation rates in conflicts with older boys (5–6-year olds) than in conflicts with same aged boys. We found no significant age or gender effects in distribution of reconciliatory repertoire or frequency of non-affiliative conflict management strategies (aggression and displacement activities, indicative of stress responses). However, 6-year-old children were more likely than younger children to mediate in conflicts in which they were not opponents, but had witnessed. Though not confirmed statistically, this phenomenon appeared more pronounced in girls than boys. Together, our results suggest that at 3 years of age, preschool children employ sophisticated behaviours to resolve conflicts, displaying remarkable receptiveness and responsiveness to reconciliatory behaviours exhibited by older opponents.]

Reconciliation and variation in post-conflict stress in Japanese macaques (Macaca fuscata fuscata): testing the integrated hypothesis.

Reconciliation in primates, a post-conflict affiliative interaction between former opponents, appears to have two functions: (1) to repair relationship damaged by aggression such that animals who share more valuable relationships are more likely to reconcile, and (2) to reduce the post-conflict uncertainty and stress of former combatants. The 'integrated hypothesis' of reconciliation links these functions by arguing that the disturbance of a valuable relationship by aggression should result in particularly high levels of stress, which in turn should facilitate efforts to reconcile and thus gain relief from post-conflict stress. A key prediction of the integrated hypothesis is that victims of aggression suffer more stress following conflicts with individuals with whom they share a valuable relationship. In this article, we test the integrated hypothesis by observing the post-conflict behaviour of victims among a free-ranging provisioned troop of Japanese macaques (Macaca fuscata fuscata) living in Shiga Heights, Nagano, Japan. In this troop, monkeys reconciled roughly one in seven conflicts. The only factor that we could significantly relate to the occurrence of reconciliation was kinship; kin reconciled more frequently than non-kin did. Receiving aggression increased and reconciliation reduced the probability of being re-attacked after aggressive interactions, supporting the hypothesis that reconciliation repairs relationships. Victims' self-directed behaviour (SDB) - a behavioural index of stress comprising increases in scratching, self-grooming, and body-shaking - was elevated following aggression but decreased rapidly following reconciliation, supporting the idea that reconciliation functions to reduce post-conflict stress. Post-conflict SDB varied as follows: (1) victims showed a higher level of stress following aggression with kin than with non-kin, and (2) juvenile victims were less distressed than adults. The level of post-conflict SDB performed by juveniles following conflicts with kin was indistinguishable from that performed by adults but was greatly reduced following attacks from non-kin. These results indicate that post-conflict SDB keenly reflects the value of relationships between opponents, and that the post-conflict behaviour of free-ranging Japanese macaques fits the predictions of the integrated hypothesis.

Methodological improvements for the study of reconciliation

The present paper suggests methodological improvements for the study of reconciliation, i.e. affiliative interactions between former opponents shortly after agonistic conflicts. Three methods have been suggested to determine whether post-conflict affiliation between former opponents is higher than what would be expected by chance. Two of these methods may fail to find this higher level when the analyses are based on long-lasting observations. The third method, however, solves this potential shortcoming by identifying the ‘relevant’ duration of the observations to be considered. We also emphasize the importance of distinguishing post-conflict affiliative interactions on the basis of their timing following a conflict in order to examine their conciliatory functions. Finally we suggest a correction of the conciliatory tendency, a measure used to compare the frequency of reconciliation between dyads of individuals that may have different baseline levels of affiliation. A comparison between the original measure and the corrected one shows that only the latter is independent of the baseline level of affiliation and is, therefore, more suitable for the study of intra- and inter-specific differences in the frequency of reconciliation.