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Proops, L., Walton, M., & McComb, K. (2010). The use of human-given cues by domestic horses, Equus caballus, during an object choice task. Anim. Behav., 79(6), 1205–1209.
Abstract: Selection pressures during domestication are thought to lead to an enhanced ability to use human-given cues. Horses fulfil a wide variety of roles for humans and have been domesticated for at least 5000 years but their ability to read human cues has not been widely studied. We tested the ability of 28 horses to attend to human-given cues in an object choice task. We included five different cues: distal sustained pointing, momentary tapping, marker placement, body orientation and gaze (head) alternation. Horses were able to use the pointing and marker placement cues spontaneously but not the tapping, body orientation and gaze alternation cues. The overall pattern of responding suggests that horses may use cues that provide stimulus enhancement at the time of choice and do not have an understanding of the communicative nature of the cues given. As such, their proficiency at this task appears to be inferior to that of domestic dogs, Canis lupus familiaris, but similar to that of domestic goats, Caprus hircus.
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Amant, R. S., & Horton, T. E. (2008). Revisiting the definition of animal tool use. Anim. Behav., 75(4), 1199–1208.
Abstract: Benjamin Beck's definition of tool use has served the field of animal cognition well for over 25 years (Beck 1980, Animal Tool Behavior: the Use and Manufacture of Tools, New York, Garland STPM). This article proposes a new, more explanatory definition that accounts for tool use in terms of two complementary subcategories of behaviours: behaviours aimed at altering a target object by mechanical means and behaviours that mediate the flow of information between the tool user and the environment or other organisms in the environment. The conceptual foundation and implications of the new definition are contrasted with those of existing definitions, particularly Beck's. The new definition is informally evaluated with respect to a set of scenarios that highlights differences from Beck's definition as well as those of others in the literature.
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Avital, E., & Jablonka, E. (1994). Social learning and the evolution of behaviour. Anim. Behav., 48(5), 1195–1199.
Abstract: Abstract. In animals capable of learning from a parent or other individual, socially acquired behaviour can be transmitted through several generations. When the inheritance of variations in such behaviour is independent of genotypic variations, natural selection can operate on an additional level. Direct evolution of behaviour becomes possible, and this may alter the estimates of costs and benefits of behaviour patterns for the individual who transmits them. It is suggested that the effects of maternally transmitted behaviour contribute to the evolution of maternal behavioural strategies, and to the evolution of behaviour associated with male-female conflict.
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Adams, E. S. (2005). Bayesian analysis of linear dominance hierarchies. Anim. Behav., 69(5), 1191–1201.
Abstract: Studies on social animals often seek to identify dominance hierarchies, in which individuals are ranked according to competitive abilities based on counts of wins and losses in pairwise encounters. I illustrate Bayesian approaches, based on the method of paired comparisons, for determining ranks and for estimating relationships between dominance ability and other attributes. Bayesian inference combines prior probability distributions for each unknown parameter with likelihood functions to produce the joint posterior probability distribution for the quantities of interest. In contrast to nonparametric techniques for inferring ranks, Bayesian models yield measures of certainty for each inference and allow rigorous estimates of correlations between ranks and covariates even when there is considerable uncertainty as to the ranks themselves. A possible objection to the Bayesian approach is that it appears to entail more restrictive assumptions than do simpler methods. However, simulations show that Bayesian inferences are more robust to deviations from these assumptions than are the results of nonparametric methods.
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Feh, C., & de Mazières, J. (1993). Grooming at a preferred site reduces heart rate in horses. Anim. Behav., 46(6), 1191–1194.
Abstract: Abstract. It is commonly suggested that the principal function of allogrooming is to reduce social tension between group members, but direct evidence of the physiological consequences of grooming at particular sites is lacking. By filming allogrooming sequences in a herd of Camargue horses, Equus caballus , their preferred grooming site, which lies on the lower neck, was identified. Experimental imitation of grooming at this site reduced the heart rate of the recipient while grooming on a non-preferred area did not, in both adults and foals. This preferred site lies close to a major ganglion of the autonomic nervous system.
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Reboreda, J. C., & Kacelnik, A. (1990). On cooperation, tit-for-tat and mirros. Anim. Behav., 40(6), 1188–1189.
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Wolff, P. R., & Powell, A. J. (1984). Urine patterns in mice: An analysis of male/female counter-marking. Anim. Behav., 32(4), 1185–1191.
Abstract: Counter-marking in mice, Mus musculus was investigated by analysing urine deposition on filter paper marked asymmetrically with urine of the opposite sex. Intact males deposited large numbers of urine spots with a marked angular bias towards previously marked quadrants. More spots were deposited on proestrous and ovariectomized donor urine patterns, their distribution being more centrifugal on oestrous urine and more centripetal in quadrants containing a large female urine spot in a central position. In contrast, castrated male mice deposited very few spots with no angular bias. Female urine patterns showed angular bias in response to intact, but not castrated male donor urine, a larger number of spots being produced by oestrous females. Thus the pattern of deposition offers scope for two-way communication of information about reproductive potential.
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Thouless, C. R., & Guinness, F. E. (1986). Conflict between red deer hinds: the winner always wins. Anim. Behav., 34(4), 1166–1171.
Abstract: Dominance relations between free-living, female red deer (hinds) (Cervus elaphus L.) on the Isle of Rhum, Scotland, were investigated. Most interactions were won by the older hind of the pair and this was the case even when both individuals had reached full body size. The younger hind was more likely to be the winner if the conflict was escalated or if the two hinds were strangers, in which case escalation was more frequent than usual. When outside their normal home range, older hinds were much more likely to lose, and younger ones more likely to win, than usual. These results can be best explained by the hinds using previous experience as a cue for conventional resolution of conflict, with the result that dominance relationships established early in life are perpetuated. No such cue is available if the hinds have not previously met.
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Frank S. A. (1996). Policing and group cohesion when resources vary. Anim. Behav., 52, 1163–1169.
Abstract: The transition from competing individuals to cooperative groups has occurred several times inevolutionary history. The puzzle is why selfish individuals did not subvert cohesive group behaviour bytaking resources without contributing to the group’s overall success. Kin selection and reciprocal altruism are the two standard explanations for group cohesion. But many groups have evolved into
cooperative units when relatedness was low and opportunities were limited for the strategic alliances required for reciprocity. A new theory was recently proposed in which individuals invest some of their resources into repressing competition between group members. Such policing increases the fair distribution of resources in the group and enhances group cohesion. The surprising aspect of this theory is that low relatedness is more conducive to the spread of policing traits than is high relatedness. Here a new explanation is developed of the biological processes that favour policing. The model is then extended in two ways. First, more realism is added to the theory by accounting for the full range of costs and benefits associated with competitive and cooperative traits within groups. Second, another surprising result is introduced about cooperative evolution. Small variations in individual vigour or resources can lead to large variations in individual contributions to policing the group. Stronger individuals often invest all of their excess resources into policing, but weaker individuals do not contribute to group cohesion. |
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Cloutier, S., Newberry, R. C., Honda, K., & Alldredge, J. R. (2002). Cannibalistic behaviour spread by social learning. Anim. Behav., 63(6), 1153–1162.
Abstract: We hypothesized that social learning is involved in the spread of cannibalism in domestic fowlGallus gallus domesticus . To investigate this hypothesis without harming birds, we used an inanimate chicken model as our cannibalism stimulus. We randomly assigned flocks of 12 White Leghorn pullets to one of two treatments: (1) flocks with two trained demonstrators (N=9) and (2) control flocks (N=8). Demonstrators were trained to pierce a membrane covering a dish of chicken blood and consume the blood. To assess the effect of access to the cannibalism stimulus during demonstrations, we randomly assigned observer pairs to one of two observer treatments: (1) observe stimulus through a wire mesh partition and (2) observe stimulus within the same enclosure. We conducted five 10-min demonstration sessions, each followed by a 10-min test of each observer pair in the absence of demonstrators, over a period of 15 days when the birds were 41-55 days of age, and two further tests at 63-64 and 91-92 days of age. Pairs that observed demonstrators piercing a membrane and consuming blood were more likely to perform this task when tested than control pairs. Learning of the task was enhanced by direct access to the cannibalism stimulus rather than observing it through a wire mesh partition. Blood consumption during tests was increased by direct access to the cannibalism stimulus during demonstration sessions. The birds made bigger holes in the membrane when tested after observing trained demonstrators and after having direct access to the stimulus. Our results provide the first experimental evidence that social learning can contribute to the spread of cannibalistic behaviour in domestic fowl. We suggest that stimulus enhancement and observational conditioning were the social-learning mechanisms involved. Copyright 2002 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved.
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