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Schilder, M. B. H. (1990). Interventions in a herd of semi – captive Plains zebras. Behaviour, 112(1-2), 53–83.
Abstract: n a herd of semi-captive plains zebras interventions, which occurred within the harems, were investigated in order to answer the question why zebras interfered. These interventions are of interest because they regulate the contacts between companions and because, as corrective and preventive measures, they reveal the normative principles underlying the behaviours by which animals structure their social environment. An attempt was made to deduce 1) the internal norms of the interferer; 2) his short term aims; 3) his tactis and 4) his perception of the social environment. The analysis revealed that in the case of an affiliative interaction foals, yearlings and adult mares started to interfere if a friend had an affiliative contact with another zebra. In view of the interferer's behaviours it was concluded that their aim was to break off the ongoing interaction and that zebras tended to protect friendship bonds. Foals and yearlings further interfered if their mother was being threatened, attacked or sexually approached by a stallion. In view of the interferer's behaviours its aim was to prevent iminent interactions or to break off ongoing interactions. This suggests that these interventions were of a protective nature. The interferer's behaviours in both contexts ware very much alike. Mares tended to interfere if their foal/yearling or adult daughter was threathened or aggressed or if a mare friend was being sexually approached by a stallion. This type of intervention was of a protective nature. Stallions in a multi male harem showed a high tendency to interfere in courtship interactions. From the resemblance between interventions in courtship and in aggressive interactions it is concluded that, at leat in a number of cases, the individuals have perceived courtship behaviour by the stallion as a threat towards the mare involved.
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Mayes, E., & Duncan, P. (1986). Temporal patterns of feeding behaviour in free-ranging horses. Behav., 96, 105–129.
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Custance DM, Whiten A, & Bard KA. (1995). Can young chimpanzees imitate arbitrary actions? Hayes and Hayes (1952) revisited. Behavior, 132, 839.
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Van Doorn G.S., Hengeveld G.M., & Weissing F.J. (2003). The Evolution of Social Dominance I: Two-player Models. Behavior, 140(10), 1305–1332.
Abstract: A difference in dominance rank is an often-used cue to resolve conflicts between two animals without escalated fights. At the group level, adherence to a dominance convention efficiently reduces the costs associated with conflicts, but from an individual's point of view, it is difficult to explain why a low ranking individual should accept its subordinate status. This is especially true if, as suggested by several authors, dominance not necessarily reflects differences in fighting ability but rather results from arbitrary historical asymmetries. According to this idea, rank differentiation emerges from behavioural strategies, referred to as winner and loser effects, in which winners of previous conflicts are more likely to win the current conflict, whereas the losers of previous conflicts are less likely to do so. In order to investigate whether dominance, based on such winner and loser effects, can be evolutionarily stable, we analyse a game theoretical model. The model focuses on an extreme case in which there are no differences in fighting ability between individuals at all. The only asymmetries that may arise between individuals are generated by the outcome of previous conflicts. By means of numerical analysis, we find alternative evolutionarily stable strategies, which all utilize these asymmetries for conventional conflict resolution. One class of these strategies is based on winner and loser effects, thus generating evolutionarily stable dominance relations even in the absence of differences in resource holding potential.
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Van Doorn G.S., Hengeveld G.M., & Weissing F.J. (2003). The Evolution of Social Dominance II: Multi-Player Models. Behavior, 140(10), 1333–1358.
Abstract: The social hierarchies observed in natural systems often show a high degree of transitivity. Transitive hierarchies do not only require rank differentiation within pairs of individuals but also a higher level ordering of relations within the group. Several authors have suggested that the formation of linear hierarchies at the group level is an emergent property of individual behavioural rules, referred to as winner and loser effects. Winner and loser effects occur if winners of previous conflicts are more likely to escalate the current conflict, whereas the losers of previous conflicts are less likely to do so. According to this idea, an individual's position in a hierarchy may not necessarily reflect its fighting ability, but may rather result from arbitrary historical asymmetries, in particular the history of victories and defeats. However, if this is the case, it is difficult to explain from an evolutionary perspective why a low ranking individual should accept its subordinate status. Here we present a game theoretical model to investigate whether winner and loser effects giving rise to transitive hierarchies can evolve and under which conditions they are evolutionarily stable. The main version of the model focuses on an extreme case in which there are no intrinsic differences in fighting ability between individuals. The only asymmetries that may arise between individuals are generated by the outcome of previous conflicts. We show that, at evolutionary equilibrium, these asymmetries can be utilized for conventional conflict resolution. Several evolutionarily stable strategies are based on winner and loser effects and these strategies give rise to transitive hierarchies.
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Poletaeva, I. I., Popova, N. V., & Romanova, L. G. (1993). Genetic aspects of animal reasoning. Behavior Genetics, 23(5), 467–475.
Abstract: This paper reviews the investigations of Prof. L. V. Krushinsky and his colleagues into the genetics of complex behaviors in mammals. The ability of animals to extrapolate the direction of a food stimulus movement was investigated in wild and domesticated foxes (including different fur-color mutants), wild brown rats, and laboratory rats and mice. Wild animals (raised in the laboratory) were shown to be superior to their respective domesticated forms on performance of the extrapolation task, especially in their scores for the first presentation, in which no previous experience could be used. Laboratory rats and mice demonstrated a low level of extrapolation performance. This means that only a few laboratory animals were capable of solving the task, i.e., the percentage of correct solutions was equivalent to chance. The brain weight selection program resulted in two mice strains with a 20% (90-mg) difference in brain weight. Ability to solve the extrapolation task was present in low-brain weight mice in generations 7-11 but declined with further selection. Investigation of extrapolation ability in mice with different chromosomal anomalies demonstrated that animals with Robertsonian translocations Rb(8,17) 1lem and Rb(8,17) 6Sic were capable of solving this task in a statistically significant majority of cases, while mice with fusion of other chromosomes, as well as CBA normal karyotype mice, performed no better than expected by chance. Mice with two types of partial trisomies and animals homo- and heterozygous for translocations were also tested. Although mice with T6 trisomy performed no better than expected by chance, animals with trisomy for a chromosome 17 fragment solved the task successfully. Thus, a genetic component underlying the ability to solve the extrapolation task was demonstrated in three animal species. The extrapolation task in animals is considered to reveal a general capacity for elementary reasoning. The genetic basis of this capacity is very complex.
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Sluyter F., Arseneault L., Moffitt T.E., Veenema A.H., de Boer S., & Koolhaas J.M. (2003). Toward an Animal Model for Antisocial Behavior: Parallels Between Mice and Humans: Aggression. Behavior Genetics, 33, 563–574.
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Morley, K. I., & Montgomery, G. W. (2001). The genetics of cognitive processes: candidate genes in humans and animals. Behav Genet, 31(6), 511–531.
Abstract: It has been hypothesized that numerous genes contribute to individual variation in human cognition. An extensive search of the scientific literature was undertaken to identify candidate genes which might contribute to this complex trait. A list of over 150 candidate genes that may influence some aspect of cognition was compiled. Some genes are particularly strong candidates based on evidence for involvement in cognitive processes in humans, mice, and Drosophila melanogaster. This survey confirms that many genes are associated with cognitive variation and highlights the potential importance of animal models in the study of human cognition.
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Bouchard, T. J. J., & Loehlin, J. C. (2001). Genes, evolution, and personality. Behav Genet, 31(3), 243–273.
Abstract: There is abundant evidence, some of it reviewed in this paper, that personality traits are substantially influenced by the genes. Much remains to be understood about how and why this is the case. We argue that placing the behavior genetics of personality in the context of epidemiology, evolutionary psychology, and neighboring psychological domains such as interests and attitudes should help lead to new insights. We suggest that important methodological advances, such as measuring traits from multiple viewpoints, using large samples, and analyzing data by modern multivariate techniques, have already led to major changes in our view of such perennial puzzles as the role of “unshared environment” in personality. In the long run, but not yet, approaches via molecular genetics and brain physiology may also make decisive contributions to understanding the heritability of personality traits. We conclude that the behavior genetics of personality is alive and flourishing but that there remains ample scope for new growth and that much social science research is seriously compromised if it does not incorporate genetic variation in its explanatory models.
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Weiss, A., King, J. E., & Figueredo, A. J. (2000). The heritability of personality factors in chimpanzees (Pan troglodytes). Behav Genet, 30(3), 213–221.
Abstract: Human personality and behavior genetic studies have resulted in a growing consensus that five heritable factors account for most variance in human personality. Prior research showed that chimpanzee personality is composed of a dominance-related factor and five human-like factors--Surgency, Dependability, Emotional Stability, Agreeableness, and Openness. Genetic, shared zoo, and nonshared environmental variance components of the six factors were estimated by regressing squared phenotypic differences of all possible pairs of chimpanzees onto 1 – Rij, where Rij equals the degree of relationship and a variable indicating whether the pair was housed in the same zoo. Dominance showed significant narrow-sense heritability. Shared zoo effects accounted for only a negligible proportion of the variance for all factors.
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