Abstract: We investigated 71 horses at five stud farms. Their breeds were Thoroughbred (n = 48), Anglo-Arab (n = 7), Thoroughbred mixed breed (n = 5), Appaloosa (n = 3), Selle Francais (n = 2), Dutch Warmblood, Haflinger, Pinto, Quarter Horse and Westfalen (n = 1, respectively), and one horse's breed was not known, but was a heavy horse. Their genders were stallion (n = 5), gelding (n = 41) and female (n = 25). Their ages ranged from 4 to 24 and the average was 11.1 +/- 5.3 (S.D.). The horses' behaviour was twice observed for 2 h both before and after feeding, using a scan sampling technique at 2 min intervals. We investigated the relationship between management factors, age, sex, breed and behavioural patterns of stabled horses, and the occurrence of weaving by a least-squares analysis of variance, a correlation analysis, Chi-square test and an analysis of behavioural sequences. Thoroughbred horses displayed weaving more than other breeds (P < 0.01) and horses in box stalls which were face to face with each other displayed weaving more than those in box stalls which were formed in a line (P < 0.01). The time budget of weaving correlated negatively with the amount of hay-cube fed (kg/day) (P < 0.05) and time budgets of drinking, bedding investigation, looking and coprophagia (P < 0.01, respectively). From the analysis of behavioural sequences, weaving followed resting (P < 0.01), looking (P < 0.01) and pawing (P < 0.05), and was followed by them (P < 0.01, P < 0.01 and P < 0.05, respectively). The least-squares analysis of variance revealed that Thoroughbred horses investigated the bedding more than other breeds (P < 0.05), horses that are usually in contact with `mainly familiar people' investigated the bedding significantly less than those usually in contact with `people including strangers' (P < 0.05), and horses in box stalls which were face to face with each other tended to investigate the bedding more than those in box stalls which were formed in a line. The time spent feeding was related to food type (min/kg), and tended to be negatively correlated with the time budget of bedding investigation behaviour. These results indicate that weaving in horses is affected by breed, stable design, feed type, and other behavioural traits.

Abstract: For species in which group membership frequently changes, it has been a challenge to characterize variation in individual interactions and social structure. Quantifying this variation is necessary to test hypotheses about ecological determinants of social patterns and to make predictions about how group dynamics affect the development of cooperative relationships and transmission processes. Network models have recently become popular for analyzing individual contacts within a population context. We use network metrics to compare populations of Grevy's zebra (Equus grevyi) and onagers (Equus hemionus khur). These closely related equids, previously described as having the same social system, inhabit environments differing in the distribution of food, water, and predators. Grevy's zebra and onagers are one example of many sets of coarsely similar fission-fusion species and populations, observed elsewhere in other ungulates, primates, and cetaceans. Our analysis of the population association networks reveals contrasts consistent with their distinctive environments. Grevy's zebra individuals are more selective in their association choices. Grevy's zebra form stable cliques, while onager associations are more fluid. We find evidence that females associate assortatively by reproductive state in Grevy's zebra but not in onagers. The current approach demonstrates the utility of network metrics for identifying fine-grained variation among individuals and populations in association patterns. From our analysis, we can make testable predictions about behavioral mechanisms underlying social structure and its effects on transmission processes.

Abstract: Abstract&nbsp;&nbsp;Social foraging is suggested to increase foraging efficiency, as individuals might benefit from public information acquired by monitoring the foraging activities of other group members. We conducted a series experiments with captive common marmosets (Callithrix jacchus) to investigate to what extent marmosets utilize social information about food location when foraging simultaneously with conspecifics. Subjects were confronted with dominant and subordinate demonstrators in three experiments which differed in the amount of information about food location available to the demonstrators. In all three experiments, the focal subjects` performance in the social condition was not enhanced in comparison to a non-social control condition. Because we could rule out kleptoparasitism and aggressive displacements as explanations, we argue that the subjects tendency for scramble competition by avoiding others and dispersing over the foraging area seems to inhibit or mask the acquisition of social information about the location of rewarded patches.

Abstract: 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.

Abstract: 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.