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Ellis, L. (1995). Dominance and reproductive success among nonhuman animals: A cross-species comparison. Ethol. a. Sociob., 16(4), 257–333.
Abstract: This paper updates and extends Dewsbury's (1982) review of the literature on dominance and reproductive success (RS). The findings from approximately 700 studies are included, over two thirds of which were unavailable to Dewsbury. In order to give a highly condensed and yet meaningful overview, the main findings are represented in four tables, one for male nonprimates, one for female nonprimates, one for male primates, and one for female primates. In the tables for males, findings are analyzed in terms of six different indicators of RS, and in the tables for females, in terms of eight RS indicators. Outside the primate order, evidence largely supported the hypothesis that high-ranking males enjoy greater RS than do subordinate males. For females, studies are more evenly divided between those supporting the hypothesis that high rank and RS are positively correlated and those indicating no significant rank-RS relationship. This may reflect both the lower saliency of hierarchical relationships among females, as well as the lower variability in RS among females, relative to males. Among primates, a complex picture has emerged, especially in the case of males. Much of the complexity appears due to the importance of age and seniority in affecting dominance rank. Also, in some primate species, female preferences for sex partners seem to have little to do with the male's dominance rank, at least at the time mating takes place. Nevertheless, the majority of studies suggest that high- to middle-ranking males have at least a slight lifetime reproductive advantage over the lowest ranking males.
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Boyd, R., & Richerson, P. J. (1995). Why does culture increase human adaptability? Ethol. a. Sociob., 16(2), 125–143.
Abstract: It is often argued that culture is adaptive because it allows people to acquire useful information without costly learning. In a recent paper Rogers (1989) analyzed a simple mathematical model that showed that this argument is wrong. Here we show that Rogers' result is robust. As long as the only benefit of social learning is that imitators avoid learning costs, social learning does not increase average fitness. However, we also show that social learning can be adaptive if it makes individual learning more accurate or less costly.
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Arnold Gw, G. A. (1982). Ethogram of agonistic behaviour for thoroughbred horses. Appl. Animal. Ethol., 8(1), 5–25.
Abstract: Social interactions between individual horses were observed in two herds each comprising a stallion and a number of mares. In one herd, the animals were observed whilst grazing and resting; in the other, nearest neighbours were recorded when the animals were grazing, and social interactions were noted when the animals were feeding on hay.
In both herds, the horses showed marked preferences for the company of specific individuals when they were grazing. In one herd, the associations were mainly between individuals that had been associated prior to being put in the herd. In the other herd, this was not the case. A new statistic was produced for testing for specific company preference. In both herds, the stallion was dominant over all mares and never received any aggression.
The complete social hierarchy could not be determined for the herd which was observed only when grazing because social contact was restricted to that within groups or pairs that associated together. In the herd to which hay was fed, a non-linear hierarchy existed. Statistics were produced to quantify both the general level of dominance of a horse and its specific dominance or subordination to every other horse. It is suggested that these statistics, and one for quantifying the general aggressiveness of a horse, could be widely used.
A principal component analysis allowed the horses to be characterised socially according to aggressiveness, their attitude to other horses and their attractiveness to other horses.
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Hampton, R. R. (2001). Animal Minds: Beyond Cognition to Consciousness. Ethology, 107, 1055–1056.
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Rendall, D. (1999). Review of Machiavellian Intelligence II: Extensions and Evaluations. Ethology, 105(2), 178–182.
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Ceacero, F., Landete-Castillejos, T., Garcia, A. J., Estevez, J. A., & Gallego, L. (2007). Kinship Discrimination and Effects on Social Rank and Aggressiveness Levels in Iberian Red Deer Hinds. Ethology, 113(12), 1133–1140.
Abstract: Abstract 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 (chi2 = 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 (chi2 = 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.
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Pannozzo, P. L., Phillips, K. A., Haas, M. E., & Mintz, E. M. (2007). Social Monitoring Reflects Dominance Relationships in a Small Captive Group of Brown Capuchin Monkeys (Cebus apella). Ethology, 113(9), 881–888.
Abstract: Abstract In several studies of social monitoring in primates, subordinate animals directed more visual attention toward dominant animals than vice versa. This behavior is thought to enable subordinate animals to avoid conflict. We sought to clarify whether visual attention behavior functions in this manner in a small captive group of brown capuchin monkeys, Cebus apella. We tested the hypothesis that social monitoring is related to dominance status. Dominance status was determined based on the directionality of aggressive behavior, and visual attention was quantified by using focal animal sampling. Subordinate animals directed significantly more visual attention toward others than dominant animals. Subordinate animals also looked more frequently at the animals that attacked them and others the most. The results indicate that social monitoring behavior in this captive group was driven by conflict-avoidance.
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Sato, S. (1982). Leadership during actual grazing in a small herd of cattle. Appl. Animal. Ethol., 8(1-2), 53–65.
Abstract: An understanding of patterns of leadership during grazing movements is important where the management of grazing cattle is concerned. This paper describes the leadership displayed by grazing cattle by recording the spatial relationship (grazing style) among herd members as the group progressed slowly through a field. Grazing style was divided into “A”, “B” and “C”, meaning following, independence and leading, respectively. The results revealed the following features: (1) the frequency distributions of grazing style and grazing formation used by the herd varied with the seasons; (2) the individual animal variation in grazing style did not fundamentally change with the seasons; (3) there was negative linear correlation between Styles A and C and between Styles A and B. The more any cow followed the grazing movement, the less likely it was to lead the grazing movement or to be independent. Styles C and B tended to be positively related; (4) high, medium and low ranking animals in social dominance showed tendencies to behave in Styles C, A and B, respectively; (5) grazing style and weight gain were not clearly related; (6) the cows that tended to lead, be independent or follow less, tended to get out of their paddocks. The observations suggested (1) that the leader-follower-independent relationship, although modified in each season, did not vary fundamentally, (2) that the active movement of high ranking animals and the independent movement of low ranking animals governed the voluntary formation in grazing, and (3) that as grazing cattle that behaved in a single group and did not escape from their paddock were much easier to manage, the grazing style that expressed these characteristics was one of the significant indices for management of grazing cattle.
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Dellert, B., & Ganslosser, U. (1997). Experimental alterations of food distribution in two species of captive equids (Equus burchelli and E. hemionus kulan). Ethol Ecol Evol, 9(1), 1–17.
Abstract: n one group each of Plains zebra (six mares, one foal, one subadult) and Asiatic wild asses (seven mares, two foals) at Nuremberg Zoo, food distribution was experimentally changed from clumped (all food in one standard hay rack) to dispersed (one heap per animal). Both groups were characterized by different social structures, which basically remained during the experiment. Plains zebras had an individually structured system of social relationships in a dominance order, wild asses a more egalitarian system without clear-cut rank differences and low frequencies of agonistic interactions. Access to food accordingly was individually (but consistently) different for zebra mares, almost equal for wild ass mares. During the dispersed feeding situation frequencies of agonistic interactions in both species decreased (however non-significantly), individual distances increased but mares also frequently ''visited'' each others' heaps. Feeding time increased for all wild ass mares. Some individuals (in both groups) behaved ''against the trend'' in agonistic behaviour. The results are discussed with regard to food distribution for ungulates in general, and equid social systems.
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Podos, J. (1964). Early perspectives on the evolution of behavior: Charles Otis Whitman and Oskar Heinroth. Ethol Ecol Evol, 6(4), 467–480.
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