Postconflict Behavior of Captive Brown Capuchins in the Presence and Absence of Attractive Food

Most of what we know about postconflict behavior comes from studies on chimpanzees and other Old World semiarboreal and semiterrestrial species. Few studies have investigated whether the context of a fight affects reconciliation—selective postconflict attraction between former opponents—and consolation: selective attraction between conflict participants and other group members. We studied social conflict and its aftermath in two captive groups of brown capuchins (Cebus apella), an arboreal New World species. We observed postconflict behavior in two contexts: (1) during the presence of highly attractive, clumped food—food condition—and (2) in the absence of such food—nonfood condition. Commercial monkey chow was available ad libitum in the nonfood condition. A comparison of postconflict and control observations revealed a conciliatory tendency in the capuchins, but only following fights that occurred in the absence of highly attractive food. Other group members tended not to seek postconflict contact with former conflict participants. However, when shortly after fights recipients of aggression, but not aggressors, initiated affiliation with third parties, the latter not only allowed proximity or contact but also often reciprocated through grooming, play, and especially the exchange of friendly signals. We discuss these results within the framework of current knowledge of postconflict behavior with special emphasis on similarities and differences in the postconflict behavior of Cebus and Pan.     

Postconflict Behavior of Spectacled Leaf Monkeys (Trachypithecus obscurus). II. Contact with Third Parties

We studied the postconflict interactions with group members other than the former opponent in two groups of spectacled leaf monkeys. We found no evidence of redirection of aggression towards other group members. Victims and aggressors sought affiliative contacts with uninvolved third parties. There was no evidence for consolation—affiliative contact initiated by an uninvolved third party, directed towards victims of aggression—in either group when all affiliative behaviors were considered. However, embracing was a characteristic first-contact interaction between individuals involved in aggression and third parties. This finding mirrors the results concerning reconciliation in spectacled leaf monkeys. Accordingly, embracing may be a true consolatory behavior in this species. When contacts with third parties occurred before or in the absence of reconciliation, the timing of such contacts fell within the time window during which reconciliation normally occurs. These contacts also resulted in affiliation levels twice that of baseline levels, supporting the idea that these contacts may function as a form of substitute reconciliation. We discuss these results in light of recent theories concerning postconflict behavior in primates.     

The Occurrence of Postconflict Skills in Captive Immature Chimpanzees (<Emphasis Type="Italic">Pan troglodytes</Emphasis>)

Conflict management strategies can reduce costs of aggressive competition in group-living animals. Postconflict behaviors such as reconciliation and third-party postconflict affiliation are widely accepted as social skills in primates and have been demonstrated in many species. Although immature primates possess a repertoire of species-specific behaviors, it is thought that they gradually develop appropriate social skills throughout prolonged juvenility to establish and maintain complex social relationships within their group. We examined the occurrence of postconflict skills in five immature chimpanzees (Pan troglodytes) over 15 mo, focusing on interactions that were not with the subject’s mother. We observed reconciliation, with conciliatory tendencies comparable to adults, and provide the first evidence that captive immature chimpanzees commonly reconciled using social play. However, immatures were not more likely to reconcile valuable than nonvaluable relationships. We also observed third party postconflict affiliation although at a lower level than reported for adults. Our results provide evidence for postconflict skills in immature chimpanzees but the lack of higher conciliatory tendency with valuable partners and low occurrence of third-party affiliation indicates extended juvenility may be required refine these skills. Further work is needed to investigate whether these behaviors have the same function and effectiveness as those found in adults.     

Postconflict affiliative contacts between former opponents among wild moor macaques (Macaca maurus)

Agonistic interactions and postconflict behavior of moor macaques (Macaca maurus) were studied in their natural habitat, South Sulawesi, Indonesia. Individuals were involved in 0.28 agonistic interactions per hour. Forty-two percent of agonistic interactions were followed by affiliative contacts between the former opponents. Such affiliative contacts occurred within 2 minutes of the agonistic interaction and were most often initiated by the victim's approach to the aggressor. The most common postconflict behavior was grooming of the aggressor by the victim. The present study provides further evidence of a positive correlation between a high tendency for postconflict affiliative contact and a relaxed dominance style. Captivity might not alter the expression of postconflict behavior. The present study suggests that it is possible to demonstrate the occurrence of reconciliation a posteriori by using data obtained by general focal observation protocols. © 1996 Wiley-Liss, Inc.     

Reconciliation in three groups of lion-tailed macaques

We studied postconflict behavior in three captive groups of lion-tailed macaques (Macaca silenus). After a conflict, we monitored the aggressee as the focal individual during a 10-min postconflict period and made control observations the following day on the same individual. Selective attraction between former opponents occurred in the first minutes of the postconflict period. The conciliatory tendency was relatively high, about 40%. Although no specific behavior was used to reconcile, postconflict contacts were especially intense and a rich repertoire of affiliative patterns was exihibited. With regard to the rate and form of reconciliation, lion-tailed macaques resemble Sulawesi macaques, which belong to the same phyletic lineage. We also discuss the possible interrelations between conciliatory patterns and other characteristics of social organization.     

Postconflict Behavior Among Male Japanese Macaques

Reconciliation was first described more than 20 years ago. Since then, it has been observed in many mammals (mainly primates) but data on postconflict behavior among males are still scarce because they usually aggressively compete for mating partners, rarely maintain amicable relationships with one another. Accordingly, reconciliation is expected to occur at low rates. Although this is true for Japanese macaque males, the subspecies on Yakushima Island (Macaca fuscata yakui) seems to represent an exception as grooming among males occurs often. We analyzed postconflict behavior among them and discuss the possible factors that may favor the occurrence of grooming and reconciliation. Selective attraction between former opponents—reconciliation—occurred soon after conflicts. Consolation—affiliative interactions between a focal animal and group members other than the former opponents occurring earlier in PCs than in MCs—was absent among males. Conciliatory tendency is higher for Yakushima macaque males (0.31) versus that in studies on the other subspecies Macaca fuscata. We discuss differences in the behavioral ecology of the 2 subspecies, the ecological and social factors that may favor the occurrence of reconciliation, and the possible benefits that males gain from grooming exchange and reconciliation.     

The Importance of Considering the Behavioral Form of Reconciliation in Studies of Conflict Resolution

Reconciliation is the most extensively studied conflict resolution mechanism in animal societies. However, despite the extensive literature on this topic, behaviors considered to represent postconflict affiliation have not been consistent across studies of reconciliation. Critically, reconciliation is usually defined as postconflict contact affiliation, e.g., grooming, and the importance of including interopponent distance regulation is often neglected. Moreover, to date, no study has simultaneously investigated different behavioral forms of reconciliation. We tested in two groups of wild Barbary macaques (Macaca sylvanus) the relative importance of postconflict close proximity and grooming in the mediation of two important costs of aggression: damage to the opponent’s social relationship and elevated postconflict anxiety. We provide evidence that close-proximity approaches function to resolve conflicts: Close-proximity approaches reduced the victim’s postconflict anxiety and were predicted by the quality of the social relationship with the opponent. Moreover, postconflict grooming alone, although predicted by the quality of the opponent’s social relationship, did not influence the victim’s elevated postconflict anxiety. Our results suggest that interopponent distance regulation plays an important role in reconciling the costs of aggression in Barbary macaques. We advocate that further efforts should be made to test which behaviors play a role in conflict resolution in different species. This is important because even closely related species may differ in the function of behaviors that superficially appear to be rather similar. Moreover, the choice of behaviors used to study conflict resolution determines the frequency with which reconciliation is observed and can thus bias comparisons across species.     

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.     

Affiliation Between Aggressors and Third Parties Following Conflicts in Long-Tailed Macaques (Macaca fascicularis)

Studies on cercopithecine monkeys have shown that soon after an agonistic conflict, victims have increased rates of affiliation with the agressor—reconciliation—but not with other group members. Postconflict affiliation is thought to function to restore disturbed relationships and to reduce social tension. This study on a captive group of long-tailed macaques (Macaca fascicularis) is focused on postconflict affiliative behavior of the aggressor. Increased rates of contact between female aggressors and kin of the victim occurred, as well as between female aggressors and their own kin. Furthermore, there were increased rates of contact between aggressors—males and females—and other group members. The increase in contacts with the victim's kin was selective, i.e., it could not be ascribed to the increased contact tendency with group members in general, and was not a side effect of the aggressor's proximity to the victim due to reconciliation. The increase in contacts with own kin was not selective. The fact that male aggressors do not have increased postconflict contacts with their kin or with kin of the victim is in agreement with the notion that males are less integrated in the nepotistic matrilineal network than females are. The fact that studies by others that focused on the victim evidence no increase in postconflict contacts with kin of the opponent or with other group members may be explained by the aggressor's larger influence over the postconflict situation: to reduce social tension, it might be more effective to affiliate with the aggressor than with the victim. Our findings emphasize that conflicts influence the behavior of other monkeys besides the direct contestants and, thus, indicate that the disturbance of social homeostasis is a matter of concern for all group members.     

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.     

Postconflict Affiliation of Aggressors in <Emphasis Type="Italic">Papio hamadryas</Emphasis>

Researchers have associated variation in the occurrence of postconflict behaviors with variation in the relationship quality between involved individuals. Apart from those on the great apes, the vast majority of postconflict studies involved female-bonded species and focused on the victim. We examined postconflict affiliation involving the aggressor in a non-female-bonded species, hamadryas baboons (Papio hamadryas), and investigated the influence of relationship quality on the occurrence of 2 types of postconflict affiliative behaviors. Hamadryas baboons reconciled after a conflict and the highest rate of reconciliation was between one-male unit (OMU) leader males and their females. Via direct measures of relationship characteristics we also found that partners with higher-quality relationship, e.g., highly affiliative dyads and allies, showed higher levels of conciliatory tendency than dyads with lower-quality relationship, e.g., less affiliative dyads and non-allies. We found evidence of postconflict third-party affiliation initiated by aggressors, but not by third parties. Further, aggressor-initiated affiliation was more likely with individuals of the same OMU and individuals with which the aggressor maintained a strongly affiliative relationship. Our findings provide further support for relationship quality as a fundamental underlying factor not only in reconciliation, but also in postconflict affiliations involving third parties.     

Resolution of aggressive conflicts by immature long-tailed macaques Macaca fascicularis

The behaviour following aggressive interactions differed from the behaviour following friendly or neutral control interactions among unrelated immature male Macaca fascicularis. Former opponents interacted again sooner and more often after aggression than after a friendly or neutral encounter. The higher rate did not reflect a general increase in social activity. The behaviour characterizing encounters between former opponents also differed in the two situations, with more affiliative interactions postconflict. In both situations, however, most interactions between former opponents were initiated by the higher-ranking aggressor. This pattern of interactions between former opponents is interpreted as a repair mechanism for relationships strained by aggression (i.e. reconciliation). A similar pattern of interactions was found for related animals, though it occurred more rarely than among non-kin.     

Ecologically based definition of seasons clarifies predator–prey interactions

Species interactions within food webs are driven by multiple constraints, including those imposed by seasonal changes in the environment. Ecologically sound definitions of seasons may therefore be a prerequisite for clarifying predator prey interactions. Most studies define biological seasons based on fixed schedules or on temporal changes in a single movement measurement. We used a novel clustering approach based on homogeneous space‐use patterns of GPS‐collared animals to reveal 7 biological seasons for caribou Rangifer tarandus caribou, and 5 for both moose Alces alces and grey wolves Canis lupus interacting in a boreal ecosystem. Subsequent evaluation of niche overlap showed that, as predicted, wolves had a stronger spatio‐temporal connection with moose, its main prey, than with caribou. Movement constraints and limiting resource distributions similarly affected all species in some instances, but also caused temporal changes in the extent of niche overlap between wolves and its two prey. The risk that caribou faced was not only linked to the niche overlap with wolves, but also to the extent of wolf‐moose niche overlap during the same period. Food‐web properties emerged from the analysis, with temporal changes in relative niche overlap reflecting the strength of trophic interactions during the year. Our study demonstrates how the study of trophic interactions can benefit from comprehensive definitions of biological seasons.     

Is Postconflict Affiliation in Captive Nonhuman Primates an Artifact of Captivity?

Researchers have conducted most studies on primate conflict management and resolution in captive settings. The few studies on groups of the same species in captivity and in the wild and the overall comparison across species of findings from studies in both settings have reported patterns of variation in the rates of various postconflict affinitive behaviors that may be setting related. In fact, some authors have claimed that the high rates of postconflict affiliation reported in captive studies could represent an artifact of captivity. I explored the claim and conclude that it is unjustified. I argue that the dichotomy captivity vs. wild is conceptually meaningless and scientists should abandon it as an explanatory variable, that differences across studies both in setting-related variables and in the methods used for assessing postconflict affiliation reduce the strength of comparisons within and across settings, that the empirical evidence thus far available neither allows adequate assessment nor supports any claim that links the rate of postconflict affiliation to captivity or wild conditions, and that studies conducted in both settings may be equally useful—and should be used—to test theoretically relevant hypotheses regarding the causes and predictors of variation in postconflict affiliation. Instead of asking the title question, I would ask which variables influence postconflict affiliation and then whether the variables are really associated only with one of the two settings.     

Female dominance in blue-eyed black lemurs(Eulemur macaco flavifrons)

Female dominance is unusual among mammals and has been described in detail for only a handful of species. Here we present data on the frequency and outcome of dominance interactions in seven semi-free ranging and captive groups of blue-eyed black lemurs (Eulemur macaco flavifrons) housed at the Duke University Primate Center. We collected over 260 hours of focal data during which all occurrences of dominant-subordinate interactions were recorded. We collected data outside the typical breeding and birthing seasons for this species, thus eliminating possible confounding factors and increased aggression associated with these periods. We found that females were dominant over males in all seven groups, with females winning 99% of all dominance interactions.E. m. flavifrons used aggressive dominance (e.g. chase, cuff, bite) in 81% of all interactions, with the remainder of interactions being decided using social dominance (e.g. deference in the form of supplants or cowers). Older females were dominant over younger females in two out of three multi-female groups (in each case, younger females were daughters), and younger males (sons of the dominant female) received less aggression from females than did older males (n = 2 groups). Caging and group size appear to play a minimal role in the expression of female dominance. While confirmation must await further observations on free-ranging groups ofE. m. flavifrons, our data strongly suggest that this subspecies can be characterized as female dominant.     

Do Ringtailed lemurs (Lemur catta) reconcile in the hour post-conflict?: A pilot study

A previous study byKappeler (1993) showed that no reconciliation occurred in the ringtailed lemur (Lemur catta). Like the majority of studies dealing with reconciliation, the post-conflict period lasted 10 minutes. An identical study using a 70-min post-conflict period was conducted on one of the same semi-free ranging group studied six years earlier byKappeler. Results showed that individuals who never interacted within 10 min did engage in friendly interactions in the longer lasting postconflict period.     

Third-party postconflict affiliation of aggressors in chimpanzees

Postconflict management strategies have been defined as any postconflict interaction that mitigates the negative consequences of the preceding agonistic conflict. Although most studies have investigated postconflict interactions between former opponents or between victims and uninvolved bystanders, interactions between aggressors and bystanders have received much less attention. In this study, we examined a database of 1,102 agonistic interactions and their corresponding postconflict periods in two outdoor-housed groups of captive chimpanzees in order to test the occurrence of postconflict third-party affiliation of aggressors. Our results confirmed the occurrence of appeasement, i.e. postconflict affiliation by a bystander toward an aggressor, but failed to detect the occurrence of postconflict affiliation directed from aggressors toward bystanders. Appeasement rates did not differ according to the sex of the involved individuals. In addition, appeasement occurred more often in the absence of reconciliation than after its occurrence suggesting that appeasement may act as an alternative to reconciliation when the latter fails to occur. Both study groups showed behavioral specificity for appeasement, i.e. context-specific use of certain behaviors, supporting the view that chimpanzees exhibit highly visible explicit postconflict affiliation.     

Female social dominance in two Eulemur species with different social organizations

Female social dominance is rare in mammals, but common in lemurs. We investigated social dominance in two Eulemur species; the polygynous crowned lemur (E. coronatus) and the monogamous red‐bellied lemur (E. rubriventer), using four and two social groups, respectively. We collected data on agonistic interactions and two types of affiliative behavior (grooming and maintaining spatial proximity). We used a combination of focal watches of individuals, instantaneous scan‐sampling of groups, and all‐occurrence of some behaviors in groups. We found that overall rates of agonistic interactions were higher in E. coronatus, and they also had more decided intersexual agonistic interactions than E. rubriventer. However, in both species the females won the vast majority of these agonistic interactions. E. coronatus females were groomed more often by males than vice versa, whereas no sex differences in grooming were observed in E. rubriventer. We found that males were responsible for maintaining spatial proximity in E. coronatus whereas in E. rubriventer, females were responsible. In one group of E. coronatus, the male was overweight and dominant to the female and this is the first observation of male dominance in a lemur species typically described as female dominant. We suggest that body weights in captivity be monitored for maintaining normal dominance relationships. Overall, agonistic behaviors were consistent with clear female social dominance in both E. coronatus and E. rubriventer. The affiliative behaviors also provided clear evidence for female dominance E. coronatus, but not for E. rubriventer. Zoo Biol 0: 1–14, 2007. © 2007 Wiley‐Liss, Inc.     

Kinship Discrimination and Effects on Social Rank and Aggressiveness Levels in Iberian Red Deer Hinds

Kin recognition is a widespread phenomenon that allows individuals to benefit by enhancing their inclusive fitness, and one of its most common forms is reducing aggressiveness towards relatives. We carried out an experiment with Iberian red deer hinds (Cervus elaphus hispanicus) in order to examine kin biases in dominance behaviour and its consequences on social rank. Three enclosed groups (n = 36, 23 and 21, respectively) were monitored during two lactation seasons and social rank hierarchies were assessed by analysing aggressive interactions matrices with Matman 1.1 software. Aggressive interactions between related hinds was significantly smaller than expected (χ² = 5.02, df = 1, p = 0.025), not only between mother and daughter but also in second and third kinship degrees. Although rates of aggressiveness were similar to data published relating free‐ranging C. e. scoticus, aggressive interactions with relatives were significantly smaller (χ² = 39.0, df = 1, p < 0.001). This reduction of aggressiveness between related hinds was not the result of these hinds having a lower social rank: social rank was only related to age and weight, but not to kinship degree, calf sex or calving date. The decrease of aggressiveness towards first‐, second‐ and third‐degree relatives shows a complex kin recognition system in deer. Possible nepotistic roles in lactation include preventing milk thefts by non‐kin and disturbing feeding of unrelated hinds.     

Aggression and Reconciliation in Cebus capucinus

Most data relating to aggressive and conciliatory behaviors are from Old World primates. We recorded agonistic interactions and post-conflict behaviors in a group of 12 white-faced capuchins (Cebus capucinus). After a conflict, we followed the aggressee as the focal individual during a 10-min postconflict period. We also conducted matched-control observations on the same individual. Conflicts involving physical contact were significantly bidirectional, and conflicts without physical contact were preferably unidirectional. Reconciliation was not be demonstrated at the group level. However, reconciliation occurred in kin and non-kin male/female dyads: their conciliatory tendencies were 48.1% and 21.2%, respectively. White-faced capuchins reconciled mainly during the first minutes after the end of the conflict. In kin and non-kin male/female dyads, selective attraction occurred, and aggressors were more likely to initiate affiliative contacts than aggressees. Hold-bottom and mount while emitting loud vocalizations were the most characteristic behaviors of reconciliation. Possible links may exist between aggressive and conciliatory patterns and other social variables.