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Houpt, K. A., & Wolski, T. R. (1980). Stability of equine hierarchies and the prevention of dominance related aggression. Equine Vet J, 12(1), 15–18.
Abstract: The dominance hierarchy of a herd of 10 Thoroughbred mares was determined twice, at an interval of 18 months, using paired feeding tests. Each mare's rank was correlated significantly between the 2 tests. This indicated that the hierarchy within the herd was stable. The offspring of dominant and subordinate mares were also tested for dominance in their own age groups. The offspring of dominant mares tended to be near the top of the hierarchy while those of middle and low ranking mares were not consistently found in the middle or bottom of their own hierarchies. Paired feeding tests were carried out on 8 ponies. During tests the time that each pony spent eating and the ponies' aggressive interactions were recorded. Two situations were used. Each pony-pair was tested when both ponies were in the same paddock and also when they were separated by a rail fence. The subordinate ponies spent significantly more time eating and the domonant pony was significantly less aggressive, when the pony-pair was separated by a fence than when they were in one paddock. It was concluded that the dominance hierarchies of adult horse groups changed very little over time and that the foals of dominant mares will tend to be dominant in their own age groups. Management practices can be used to reduce aggression and consequent injury that may arise in group feeding situations.
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Hrdy, S. B. (1974). Male-male competition and infanticide among the langurs (Presbytis entellus) of Abu, Rajasthan. Folia Primatol (Basel), 22(1), 19–58.
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Huxley, J. (2006). Equine interspecies aggression (Vol. 159).
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Jennings, D. J. (2014). Limited evidence that visual lateralization is associated with fitness in rutting male fallow deer. Anim. Behav., 92, 85–91.
Abstract: Under certain models of animal competition, individuals are expected to gather information about opponent quality in order to determine whether they should fight or withdraw. However, the ability to process complex information differs between individuals and across brain hemispheres: a feature of vertebrate cognition known as lateralization that is not anticipated by contest models. I investigated the relationship between aggressive behaviour and mating success during the fallow deer, Dama dama, rut and a measure of lateralization derived from eye preference during parallel walking. Results show that there was no relationship between the tendency to escalate to fighting or predictability in the tendency to engage in fighting and lateralization. Conversely, there was a quadratic relationship between third-party intervention behaviour and lateralization: the greater the tendency to intervene in ongoing fights the lower the degree of lateralization. However, individuals that showed lateralization for right-eye use were least likely to be targeted by the intervening male; thus lateralization is beneficial in this context because targeted males are highly likely to lose this subsequent encounter. The relationship between lateralization and mating success was also nonlinear: males that showed little evidence for an eye bias during lateral displays had the greatest mating success. Taken together, individuals that showed lateralization benefited from avoiding being targeted after third-party intervention; conversely, individuals that showed little evidence for lateralization actively intervened during ongoing fights and had higher mating success. These results suggest that, although lateralization does appear to confer a fitness advantage on individuals, this is not as extensive as anticipated.
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Johnstone, R. A. (2001). Eavesdropping and animal conflict. Proc. Natl. Acad. Sci. U.S.A., 98(16), 9177–9180.
Abstract: Fights between pairs of animals frequently take place within a wider social context. The displays exchanged during conflict, and the outcome of an encounter, are often detectable by individuals who are not immediately involved. In at least some species, such bystanders are known to eavesdrop on contests between others, and to modify their behavior toward the contestants in response to the observed interaction. Here, I extend Maynard Smith's well known model of animal aggression, the Hawk-Dove game, to incorporate the possibility of eavesdroppers. I show that some eavesdropping is favored whenever the cost of losing an escalated fight exceeds the value of the contested resource, and that its equilibrium frequency is greatest when costs are relatively high. Eavesdropping reduces the risk of escalated conflict relative to that expected by chance, given the level of aggression in the population. However, it also promotes increased aggression, because it enhances the value of victory. The net result is that escalated conflicts are predicted to occur more frequently when eavesdropping is possible.
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Jolly, A. (1998). Pair-bonding, female aggression and the evolution of lemur societies. Folia Primatol (Basel), 69 Suppl 1, 1–13.
Abstract: Lemur societies have been described as convergent with those of anthropoids, including Papio-like female-bonded multi-male groups. Recent research, however, shows at least 5 pair-bonded species among the Lemuridae and Indriidae. Three more, Eulemur mongoz, Eulemur fulvus and Varecia variegata, have societies combining aspects of pairing with aspects of troop life. The best-known female-bonded societies, those of Lemur catta, Propithecus diadema edwardsi and Propithecus verreauxi, may be assemblages of mother-daughter dyads, capable of high aggression towards other females, but derived from more solitary female ancestors, perhaps also living as pairs. The internal structure of such lemur groups differs from the more extensive kin groups of catarrhines. This in turn may relate to the lemurs' level of social intelligence and to lemur female dominance over males.
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Jonart, L. M., Hill, G. E., & Badyaev, A. V. (2007). Fighting ability and motivation: determinants of dominance and contest strategies in females of a passerine bird. Anim. Behav., 74(6), 1675–1681.
Abstract: The communication of aggressive motivation or fighting ability has important fitness consequences for competing animals. Selection should favour rapid and honest communication between opponents to settle dominance relationships while avoiding prolonged and intense fighting. We investigated factors that influence fighting strategies and contest outcomes in female house finches, Carpodacus mexicanus, specifically focusing on the following questions. (1) What social contexts trigger an aggressive response? (2) Does body size and condition contribute to female fighting ability? (3) Do contextual factors, such as mate presence, nest status, nest proximity, and site experience contribute to fighting motivation? (4) Does contest intensity and duration increase as the differences in fighting ability between opponents decrease? (5) What is the relative contribution of fighting ability and aggressive motivation to the outcome of a contest? We found that aggression was triggered most frequently by female intrusions in the vicinity of nest and by extrapair female intrusions on an established pair. Female fighting and contest outcomes were strongly influenced by body condition and body size, and females were more motivated to initiate fights and won more contests when their mates were present. Females at the later breeding stages and those fighting closer to their nests were dominant and won more fights compared to females at earlier breeding stages or further from their nests. Females initiated a greater proportion of contests against opponents with similar local familiarity and breeding history. Escalated and prolonged contests, while rare, occurred exclusively between females of the most similar body size and condition. When differences in body condition between opponents are not easily perceived, contestants might escalate contests for more reliable assessments of relative fighting ability. Finally, body condition was not a strong determinant of contest outcome in the contexts with easily assessed differences in the resource value (e.g. mate presence), but without these motivational differences, body condition was the ultimate determinant of contest outcomes.
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Judge, P. G., de Waal, F. B., Paul, K. S., & Gordon, T. P. (1994). Removal of a trauma-inflicting alpha matriline from a group of rhesus macaques to control severe wounding. Lab Anim Sci, 44(4), 344–350.
Abstract: Wounding in an 83-member group of rhesus macaques (Macaca mulatta) housed at the Yerkes Regional Primate Research Center Field Station became excessive to the point that intervention was deemed necessary. When observations indicated that three females from the group's alpha matriline were principally responsible for the wounding, the matriline (N = 7) was removed from the group. This study was conducted to document an atypical pattern of wounding in this group and to evaluate the effectiveness of removal as a procedure for controlling injuries. The aggression rates of 21 adult subjects and the wounds of all group members were recorded before and after the removal procedure and compared with those in a similar-sized group. Removing the alpha matriline did not alter aggression rates in the group or the rank order among the remaining matrilines. Aggression rates in the experimental group were also not significantly different from those in the comparison group before or after the removal. With the alpha matriline present, wounding levels in the group were significantly higher than those in the comparison group. After removal of the matriline, the frequency of wounds decreased significantly to levels similar to those of the comparison group. The pattern of excess wounding attributed to the extracted alpha females was idiosyncratic, involving removal of large patches of skin from the hindquarters of adult females or removal of the distal portion of the fingers, toes, or tail from juveniles.(ABSTRACT TRUNCATED AT 250 WORDS)
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Judge, P. J. (1991). Dyadic and triadic reconciliation in pigtail macaques (Macaca nemestrina). Am. J. Primatol., 23, 225–237.
Abstract: The tendency in primates for former antagonists to approach and affiliate following aggression has been termed reconciliation because the response is thought to resolve social conflicts produced by aggression. In primate societies, however, an aggressive interaction between two individuals often spreads to include other group members, especially the kin of the combatants. If post conflict affiliation resolves aggressive conflicts in a group, then affiliative increases might occur between combatants and the kin of their opponents following aggression as well as between former opponents. This hypothesis was tested in a captive group of 39 pigtail macaques (Macaca nemestrina) by comparing affiliative response frequencies of combatants during the 5 minute period following aggression to affiliative response frequencies during 5 minute baseline periods not preceded by aggressive activity. Following aggression, affiliation rates increased between combatants and their opponents, aggressors and the kin of their opponents, and aggressors and their own kin. Additional analyses showed that aggression among kin was reconciled more often than aggression among nonkin. Recipients of aggression reconciled with their attackers more often than aggressors reconciled with their victims. Animals with similar dominance ranks reconciled proportionately more often than those with large rank disparities and aggressive infractions of a calculated dominance hierarchy were reconciled more often than attacks consistent with the hierarchy. Results suggest that both dyadic and triadic reconciliations occur in M. nemestrina and that compared to other primate species M. nemestrina exhibit a moderate-to-high conciliatory tendency.
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Kawamura, S. (1967). Aggression as studied in troops of Japanese monkeys. UCLA Forum Med Sci, 7, 195–223.
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