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.     

The Function and Determinants of Reconciliation in <Emphasis Type="BoldItalic">Pan troglodytes</Emphasis>

Reconciliation (the postconflict affiliative reunion between former opponents) may mitigate costs of aggressive conflict by repairing the opponents’ relationship and reducing stress. We showed that postconflict levels of self-directed behavior were lower after reconciliation than when reconciliation did not occur in chimpanzees (Pan troglodytes) at Chester Zoo, providing support for a stress-alleviating function for reconciliation. Further, we investigated the effects of multiple factors on the occurrence of reconciliation using generalized linear mixed models. We performed 2 separate analyses, a “traditional” analysis and a “targeted” analysis. The former included variables previously used to assess the occurrence of reconciliation in primates, i.e., conflict characteristics, sex combination, and a simple measure of relationship value. The latter included species-specific variables such as the occurrence of consolation (postconflict affiliation from a bystander to the recipient of aggression); initiation of the conflict with a bluff display; and measures of relationship value, compatibility, and security specific to the study group. Whereas the traditional analysis showed that female-female dyads and valuable partners were most likely to reconcile, the targeted analysis showed that reconciliation was less likely to occur when consolation took place or when aggression was initiated with bluff displays. Further analyses revealed that the effect of sex-combination on reconciliation was due to its intercorrelation with bluff display. This study highlights the importance of considering variables specific to the study species and group when investigating the determinants of reconciliation and warns against premature interpretation of results without due consideration for all other possible determinants.     

Reconciliation, relationship quality, and postconflict anxiety: testing the integrated hypothesis in captive chimpanzees

Reconciliation is a conflict resolution mechanism that is common to many gregarious species with individualized societies. Reconciliation repairs the damaged relationship between the opponents and decreases postconflict (PC) anxiety. The "integrated hypothesis" links the quality of the opponents' relationship to PC anxiety, since it proposes that conflicts among partners with high relationship quality will yield high levels of PC anxiety, which in turn will lead to an increased likelihood of reconciliation. We tested the integrated hypothesis in captive chimpanzees (Pan troglodytes) in the Arnhem Zoo, The Netherlands. We applied the standard PC/matched control (MC) method. Our results mostly support the integrated hypothesis, in that more valuable and compatible partners (i.e., males and frequent groomers) reconciled more often than less valuable and weakly compatible partners (i.e., females and infrequent groomers). In addition, PC anxiety was higher after conflicts among males than among females. Emotional arousal thus appears to be a mediator facilitating reconciliation. However, in contrast to the predictions derived from the integrated hypothesis, PC anxiety appeared only in aggressees, and not in aggressors, of conflicts. This suggests that while relationship quality determines PC anxiety, it is dependent on the role of the participants in the conflict.     

How to Repair Relationships – Reconciliation in Wild Chimpanzees (Pan troglodytes)

Reconciliation appears to repair the relationships of former opponents after being disturbed by aggressive interactions. Despite a consensus about the benefit of reconciliation, how former opponents achieve this benefit remains unclear. Variation within reconciliation is evident in many species, but understanding what causes the variation has been mostly neglected until now. We collected 178 events of reconciliation of both sexes in a community of wild chimpanzees (Pan troglodytes) in the Taï National Park, Côte d'Ivoire. Our data provide evidence for the relationship‐repair function of reconciliation, as aggression disturbed tolerance levels among former opponents and reconciliation restored tolerance to normal levels again. Partners with highly beneficial relationships reconciled more often compared with partners of low mutual benefit. Latency and duration of reconciliation varied in combination, such that short reconciliations were initiated soon after the conflict, while long reconciliations were initiated later. Latency increased with the risk of further aggression, while duration decreased when costs were incurred from interruption of beneficial activities. In contrast, the complexity of reconciliation varied according to the intensity of the preceding conflict, such that reconciliation was more complex after more intense conflicts. Our results suggest that relationships between opponents are increasingly disturbed with increasing conflict intensity and reconciliation repairs all relationships independent of their relationship value. We propose that the function of reconciliation is to reduce the disturbance created by aggression, but the more frequent the reconciliation, the more beneficial it is for former opponents.     

Methodological and Evolutionary Aspects of Reconciliation among Primates

Affinitive contact between former opponents soon after a conflict has been demonstrated in a growing number of primate species. Several recent studies show that such contact reduces the probability of future conflicts, allows the recipient of aggression to reduce its anxiety, and restores tolerance between former opponents. Hence, these contacts can be termed reconciliation. In this paper, we critically discuss common methodological problems of studying reconciliation, examine functional aspects, and evaluate the existing variation in primate reconciliation in light of predictions derived from four untested hypotheses about its evolutionary origins. We find that the occurrence of reconciliation in primates is not limited to anthropoids. Neither is it limited to species with formalized dominance relations. Reconciliation is also not a prerequisite for life in permanent social groups. Instead, several lines of evidence support the hypothesis that reconciliation serves to maintain valuable social relationships between individuals. We suggest several more specific versions of this hypothesis and discuss reconciliation between kin, mates, and alliance partners, as well as a number of open questions pertaining to the mechanisms, functions and origins of reconciliation among primates.     

Post‐Conflict Non‐Aggressive Behaviours may be neither Friendly nor Conciliatory: Conflict Management of Male Hamadryas Baboons

The relational model of conflict resolution predicts that after an aggressive conflict there should be a motivational shift from aggression to attraction. Most tests of the reconciliation hypothesis assume, however, that all non‐aggressive post‐conflict behaviours between former opponents are motivationally homogeneous and qualify as friendly reunions. In fact, although the hypothesis predicts an increased occurrence of friendly contacts after conflicts, in practice, however, post‐conflict reunions often include a mixture of contact and non‐contact behaviours. Most reconciliation studies either (often) assume a conciliatory function for post‐conflict reunions or (less often) test functional predictions. Finally, the valuable relationships hypothesis predicts that conciliatory rates should be relatively higher between friends and allies than between non‐friends/allies. In this paper, we use data on non‐aggressive interactions following conflicts between adult male hamadryas baboons that are neither friends nor allies to assess the implications of all these important but largely overlooked issues. The analyses of the rate and temporal relation of non‐contact greeting (NCTG) to anxiety‐related behaviours and side‐directed aggression as well as of the behaviours used during non‐aggressive interactions with male and female third‐parties suggest that the NCTG used by males after conflicts were neither motivationally friendly nor functionally conciliatory. We point out that the gestures exchanged during these post‐conflict NCTG can be interpreted as formalized signals of equal status and that the rate and form of the greetings used by male opponents are indicative of high relationship insecurity and incompatibility respectively. We conclude that although male hamadryas’ post‐conflict NCTG are not conciliatory they may serve to assess their opponents’ attitude and to negotiate the restoring of their pre‐conflict levels of peaceful but non‐amicable co‐existence.     

Reconciling with Valuable Partners by Long-tailed Macaques

In primates and other social mammals, opponents in aggressive conflicts have been reported to seek one another out after fights for various types of friendly interaction. In long-tailed macaques, these friendly reunions have been shown to restore aspects of the social relationship of the opponents to their preconflict state, and they have thus been interpreted as reconciliations. Although postconflict reconciliation would seem to be adaptive to gregarious animals that establish individualized social relationships, its occurrence is variable among species, groups and dyads. Some of this variation probably reflects costs and benefits of reconciling in different situations. One factor that might influence the benefit of reconciliation and hence its occurrence is the value of the social partner as a social or ecological resource: reconciliation should occur more often after fights with valuable social partners. We conducted an experiment to test this hypothesis using pairs of monkeys (Macaca fascicularis) as their own controls. First, baseline rates of reconciliation after experimenter-induced conflict were measured. Then, the value of the relationship, at least in the test context, was increased by training each pair of monkeys to perform a simple cooperative task in which each got access to food only if the partner fed nearby simultaneously. Finally, the reconciliation rate was measured again after training and compared to its baseline value. In 6 of 7 dyads, the reconciliation rate increased after training, and the median reconciliation rate after training was 3 times higher than at baseline. While the results are consistent with the value hypothesis, there are other potential explanations. Comparison of friendly behavior when there had been no prior aggression in baseline and post-training phases, however, suggested that the increase in reconciliation rate was neither the result of a general increase in compatibility nor the result of anticipated conflict in the cofeeding context.     

Effect of valuable relationship on reconciliation and initiator of reconciliation in captive bottlenose dolphins (<Emphasis Type="Italic">Tursiops truncatus</Emphasis>)

Reconciliation, post-conflict affiliation between former opponents, was suggested to repair the relationship between former opponents. The number of times that each former opponent initiates reconciliation may be affected by the dominance style. Despotic dominance style was suggested to restrain the initiation of reconciliation by recipients of aggression, unlike relaxed dominance style. Although reconciliation was suggested to restore relationships, reconciliation sometimes did not occur. The valuable relationship hypothesis predicts that reconciliation is more likely to occur when former opponents share a valuable relationship. However, few studies have tested this hypothesis in non-primate species. This study investigated, in captive bottlenose dolphins, which are suggested as having a relaxed dominance style, whether aggressors or recipients of aggression initiate reconciliation, and whether relationships between former opponents affect the occurrence of reconciliation. The number of times that aggressors or recipients of aggression initiate reconciliation did not differ. Recipients of aggression initiated reconciliation sooner than aggressors. These results support the prospect that recipients of aggression are not impeded in initiating reconciliation in relaxed species. Former opponents who share a more affiliative relationship were reconciled more frequently. Bottlenose dolphins were suggested to receive the benefits from individuals who shared more affiliative relationships. The valuable relationship hypothesis may be supported in bottlenose dolphins.     

Anxiety Level Predicts Post-Conflict Behaviour in Wild Japanese Macaques (Macaca fuscata yakui)

Reconciliation (i.e. the post-conflict exchange of friendly behaviour between former opponents) functions to control for the detrimental effects that aggression may have on social relationships. Studies conducted so far have investigated intra-individual sources of variation in post-conflict behaviour, showing that animals have a stronger increase in anxiety and are more likely to reconcile after conflicts with valuable partners, such as kin. Much less attention has been given to how differences between individuals in emotional profiles affect post-conflict behaviour. Our aim was to analyse whether inter-individual differences in baseline anxiety levels predicted the magnitude of the increase in anxiety following a conflict and the occurrence of reconciliation. We collected data on two groups of wild Japanese macaques ( Macaca fuscata yakui ). Animals having a higher baseline level of anxiety had a more dramatic anxious response following a conflict while controlling for a series of factors (e.g. relationship quality between opponents). These more anxious animals were also less likely to reconcile than more relaxed individuals. Therefore, more anxious animals face some social costs by being less able to cope with the post-conflict condition. We propose that differences in anxiety levels may be interpreted as tradeoffs between benefits and costs across conditions. For example, more anxious animals, who are less able to reconcile conflicts, might also be less exploratory and thus face a lower risk to eat unknown, poisonous food.     

Post-conflict Social Events in Wild Mountain Gorillas (Mammalia,Hominoidea). I. Social Interactions between Opponents

Researchers have documented elevated rates of affinitive interaction between opponents shortly after aggressive conflicts, or reconciliation, in many primate species. Reconciliation may ameliorate the immediate negative effects of aggression by reducing the chance of further aggression between opponents and thus reducing tension, and may avert or repair damage to long-term social relationships important to the animals' fitness. Data on post-conflict interactions between opponents in two groups of wild mountain gorillas (Gorilla gorilla beringei) fail to show reconciliation after conflicts between females, between males, or between immatures, but females seem to commonly reconcile themselves with males after receipt of male aggression. Females and subordinate males often avoid same-sex opponents after conflicts. Females commonly retaliate against female aggressors, and post-conflict rates of aggression between females are higher than baseline levels. Females may not need to achieve reconciliation with each other because relationships between co-resident relatives are resiliant, while those between non-relatives are mostly neutral to antagonistic. Males are, however, important social partners and protectors of females, and female transfer is common. Thus, the results strongly support the ‘important relationships’ hypothesis for the function of reconciliation.     

Reconciliation in Male Stump‐tailed Macaques (Macaca arctoides): Intolerant Males Care for Their Social Relationships

Recent research has shown that social relationships may exert positive effects on fitness. Therefore, it is expected that animals make efforts to develop and preserve close social bonds. Reconciliation is a conflict resolution mechanism, which allows buffering the negative effects of aggressive conflict on social relationships. As socioecological theories claim that intrasexual competition and conflict‐shaped social interactions among macaque males, postconflict behaviour should reflect the effects of these evolutionary forces. Here, we present the results of a study on a provisioned group of Macaca arctoides in Thailand focusing exclusively on male postconflict behaviour. Through an Information Theory–Model Selection approach, we evaluated the relative support for three predictions about the occurrence of reconciliation and the quality of the opponents' social relationships. The strength of the opponents' affiliative relationship was the only variable predicting reconciliation occurrence. This agrees with the main prediction of the valuable relationship hypothesis for the function and distribution of reconciliation, which states that the opponents sharing high‐quality relationships are more likely to reconcile, and this interaction is aimed to repair the disturbing effects of previous aggression on their relationship. The conciliatory tendency found among these wild males is much lower than reported previously for this species from captive conditions, matching more closely the rates reported for species with an intolerant‐despotic dominance style. The results offer strong support for the importance of developing and preserving valuable relationships, even among rather intolerant males.     

Following the rules: why small groups of tamarins do not reconcile conflicts

Reconciliation is the post-conflict friendly reunion between opponents. A series of conditions and rules in order for reconciliation to take place has been recently proposed. One critical condition is that the relationship between opponents must be disrupted. We tested this condition using post-conflict and matched-control observations on 4 small groups of tamarins (Saguinus labiatus). Our previous lack of evidence for reconciliation was confirmed. No post-conflict relationship damage was therefore expected. We found evidence that relationships were disturbed following conflicts over food but, as in other primates, no evidence for reconciliation following such conflicts was found. For non-food-related conflicts there was no evidence that relationships were disturbed, as opponents were in close proximity to each other and resumed the exact same activity as frequently in the post-conflict observations as they did in the matched-control observations. We conclude that 'everyday' aggression may not disrupt the relationships among individuals from the same family group and therefore reconciliation is not needed.     

Postconflict Affiliation Between Former Opponents in Macaca thibetana on Mt. Huangshan, China

We describe basic patterns of postconflict affiliation between former opponents within a group of wild, provisioned Tibetan macaques Macaca thibetana on Mt. Huangshan, China. Like most primates studied to date, Tibetan macaques reconciled, i.e., overall they engaged in affiliative interaction with opponents at higher rates immediately after an aggressive conflict than at other times. Probabilities of affiliation were enhanced ≤30 s after the end of hostilities. However when we examined sex partner combinations separately, we found unequivocal evidence for reconciliation only for male-male dyads. Tolerant interaction among other partner combinations apparently was not disrupted after a conflict, presumably obviating the need to reconcile. One aspect of reconciliation among males was consistent with other indications of a despotic dominance style: aggressors initiated a higher proportion of affiliative interactions after a conflict than at other times. Another aspect of reconciliation was more typical of relaxed dominance styles: males used specialized behaviors (embraces and same-sex mounts) disproportionately to reconcile. We also found inconsistent evidence for the valuable relationship hypothesis; probabilities of reconciliation were enhanced for male-male dyads with the closest affiliative relationships, but not for those that displayed the most tolerance or mutual agonistic support. We discuss reconciliation and other aspects of conflict management among males in the context of a group with nearly even sex ratios and high male-male mating competition.     

Grooming coercion and the post-conflict trading of social services in wild Barbary macaques

In animal and human societies, social services such as protection from predators are often exchanged between group members. The tactics that individuals display to obtain a service depend on its value and on differences between individuals in their capacity to aggressively obtain it. Here we analysed the exchange of valuable social services (i.e. grooming and relationship repair) in the aftermath of a conflict, in wild Barbary macaques (Macaca sylvanus). The relationship repair function of post-conflict affiliation (i.e. reconciliation) was apparent in the victim but not in the aggressor. Conversely, we found evidence for grooming coercion by the aggressor; when the victim failed to give grooming soon after a conflict they received renewed aggression from the aggressor. We argue that post-conflict affiliation between former opponents can be better described as a trading of social services rather than coercion alone, as both animals obtain some benefits (i.e. grooming for the aggressor and relationship repair for the victim). Our study is the first to test the importance of social coercion in the aftermath of a conflict. Differences in competitive abilities can affect the exchange of services and the occurrence of social coercion in animal societies. This may also help explain the variance between populations and species in their social behaviour and conflict management strategies.     

Sex Differences in Reconciliation and Post-Conflict Anxiety in Bonnet Macaques

Rates of reconciliation vary widely between different types of opponents, and post‐conflict anxiety has been proposed to mediate individual variation in reconciliation rates. We investigated the form and function of reconciliation in a wild, provisioned group of bonnet macaques (Macaca radiata) with the prediction that sex differences in post‐conflict anxiety would be associated with sex differences in conciliatory tendency. Individuals in the study group had a conciliatory tendency of 29.3%. Victims avoided their former opponents at a higher rate following aggression than during matched‐control samples, and reconciliation decreased the rate of avoidance. Although victims showed a higher rate of anxiety‐related behavior than did aggressors, anxiety‐related behavior was elevated after aggression and reduced following reconciliation in both victims and aggressors. Female–female opponents showed higher rates of anxiety‐related behavior before reconciliation than they did following unreconciled aggression. In contrast, male–male and female–male opponents showed increased anxiety‐related behavior following aggression regardless of the occurrence of reconciliation. Moreover, female–female opponents had a higher conciliatory tendency than did female–male opponents. The elevated post‐conflict anxiety shown by female–female opponents before reconciliation, along with their high conciliatory tendency, suggests that post‐conflict anxiety promotes reconciliation. In sum, the sex differences in post‐conflict behavior found in this study support the hypothesis that variation in post‐conflict anxiety mediates differential rates of reconciliation.     

Conflict resolution following aggression in gregarious animals: a predictive framework

Knowledge of how animals manage their conflicts is critical for understanding the dynamics of social systems. During the last two decades research on gregarious animals, especially primates, has focused on the mechanisms of conflict management, mainly on friendly postconflict reunions (also called ‘reconciliation’) in which former opponents exchange affiliative behaviour soon after an aggressive conflict. Our aim in this paper is to present a framework in which the costs and benefits of friendly postconflict reunions, both for each individual opponent and for their mutual relationship, are used to predict the patterning of postconflict resolution mechanisms in other gregarious animals. The framework predicts the occurrence of postconflict reunions in species that live in stable social units, have individualized relationships, and experience postconflict hostility, but especially in those in which intragroup aggression disrupts valuable relationships. The critical issue is whether aggressive conflicts occur between cooperative partners and whether the level of aggression is sufficient to jeopardize the benefits associated with such valuable relationships. We conclude by proposing four research priorities to evaluate the role of friendly reunions in negotiating relationships and the way they are themselves influenced by asymmetries in partner value and biological market effects. Copyright 2002 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved.     

Reconciliation and the Costs of Aggression in Wild Barbary Macaques (Macaca sylvanus): A Test of the Integrated Hypothesis

The ‘integrated hypothesis’ predicts that reconciliation (the post‐conflict friendly interaction between former opponents observed in various group‐living species) functions to reduce anxiety and the risk of aggression from the former opponent or a bystander in the aftermath of a conflict. It also predicts that relationship quality between opponents affects the occurrence of reconciliation and modulates the anxious response of the opponents after a conflict. Because of the asymmetric nature of aggressive interactions, the cost of aggression is likely to differ between the victim and the aggressor. The aim of this study was to test the predictions of the ‘integrated hypothesis’ independently for the victim and the aggressor of a conflict. We collected data on two wild groups of Barbary macaques. This study represents, to our knowledge, the first systematic test of the integrated hypothesis on wild, non‐provisioned animals. Victims of aggression were at a greater risk of receiving aggression from the former opponent or a bystander after a conflict and showed elevated anxiety. We found no such costs for the aggressor. Reconciliation reduced anxiety in the victim but did not reduce their risk of receiving aggression. Finally, relationship quality affected the occurrence of reconciliation but did not modulate post‐conflict anxiety. The results of our study show that the costs of aggression are asymmetrically distributed between the victim and the aggressor. Such differences are likely to lead to different social tactics used by the victim and the aggressor in the aftermath of a conflict.     

Postconflict third-party affiliation in rooks, Corvus frugilegus

Conflict features in the lives of many animal species and induces social stress mediated by glucocorticoid hormones [1]. Postconflict affiliation, between former opponents (reconciliation) or between former opponents and a bystander (third-party affiliation), has been suggested as a behavioral mechanism for reducing such stress [2], but has been studied almost exclusively in primates [3]. As with many primates, several bird species live in social groups and form affiliative relationships [4]. Do these distantly related animals also use affiliative behavior to offset the costs of conflict? We studied postconflict affiliation in a captive group of rooks. Unlike polygamous primates, monogamous rooks did not reconcile with former opponents. However, we found clear evidence of third-party affiliation after conflicts. Both initiators and targets of aggression engaged in third-party affiliation with a social partner and employed a specific behavior, bill twining, during the postconflict period. Both former aggressors and uninvolved third parties initiated affiliative contacts. Despite the long history of evolutionary divergence, the pattern of third-party affiliation in rooks is strikingly similar to that observed in tolerant primate species. Furthermore, the absence of reconciliation in rooks makes sense in light of the species differences in social systems.     

Reconciliation in wild white-faced capuchins (Cebus capucinus)

The likelihood of reconciliation (defined as preferential peaceful contact among former opponents following conflicts) has been predicted to vary positively with relationship value and compatibility, and negatively with relationship security. Long-term data on wild white-faced capuchins (Cebus capucinus) indicate that dyads consisting of an adult female and an alpha male have high value and compatibility, but low security. Two studies of C. capucinus postconflict (PC) behavior were carried out at Lomas Barbudal Biological Reserve, Costa Rica. One study consisted of 30-min PC and matched control (MC) follows. The second study extracted PC and MC periods from long follows, yielding PC/MC periods averaging 105 min. In study 2, but not study 1, significantly more PC/MC pairs were attracted (former opponents affiliated with each other sooner in the PC period than in the MC period) than were dispersed (former opponents affiliated with each other sooner in the MC period than in the PC period). Reconciliation in study 2 could not be explained as a by-product of former opponents' tendency to seek affiliative contact with conspecifics generally, or of the spatial proximity of opponents following conflicts. Attempted reconciliation was less likely to be followed by renewed aggression when reconciliation attempts were delayed following conflicts. The data were insufficient for a formal test of differences in conciliatory tendency (the difference between the number of attracted and dispersed PC/MC pairs, divided by the total number of pairs) among dyad types to be conducted.     

Reconciling conflicts in a one-male society: the case of geladas (<Emphasis Type="Italic">Theropithecus gelada</Emphasis>)

Animals derive benefits from living in social groups but sociality also has its costs in that animals must compete with others for resources and mating opportunities. To cope with the conflict aftermath and social damage caused by competitive aggression, several group-living species use a variety of peace-keeping strategies. The affinitive post-conflict reunion of former opponents, defined as reconciliation, is the primary peace-keeping mechanism. In this study, we provide evidence for the occurrence of reconciliation and test some hypotheses on this post-conflict mechanism in geladas (Theropithecus gelada), a species often neglected in the study of post-conflict dynamics. The conciliatory contacts were uniformly distributed across the different sex–class combinations. Different from baboons, geladas did not show any particular kind of affinitive reconciliation behaviour. Notwithstanding the presence of a linear hierarchy, the dominance relationships did not affect the reconciliation dynamics. According to the valuable relationship hypothesis, coalitionary support seems to be a good predictor for a high level of conciliatory contacts. Finally, at an immediate level reconciliation plays a role in reducing renewed attacks by aggressors, which sought conciliatory contact more frequently than victims. In conclusion, even though the study of post-conflict behaviour in geladas needs to be continued, the patchy nature of their social network is a good model for testing some of the theoretical assumptions about primate conflict resolution.