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RHO, J. R., SRYGLEY, R. B., & CHOE, J. C. (2004). Behavioral ecology of the Jeju pony (Equus caballus): Effects of maternal age, maternal dominance hierarchy and foal age on mare aggression. Ecol. Res., 19(1), 55–63.
Abstract: On Jeju Island, Korea, dominance hierarchy and maternal care according to maternal age were studied in a herd of Jeju ponies (Equus caballus), consisting of 73 mares, their foals and one stallion. Dominance ranks were nearly linear and increased significantly with the age of mares. Most aggressive encounters involved mares under 5 years old. Mares under the age of 5 years have apparently not established their rank. The mean frequency of aggressive actions of mares per hour increased significantly as the day of parturition approached. Aggressive actions of mares with foals decreased significantly as their foals aged. The overall frequency of aggression of mares with foals also decreased significantly with the age of the mares. Our results suggest that the cost of maternal care is lower for older, more dominant mares than for subordinate ones.
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Cheney, D. l., & Seyfarth, R. M. (2004). Social complexity and the information acquired during eavesdropping by primates and other animals. In P. K. McGregor (Ed.), Animal Communication networks. Cambridge, Massachusetts: Cambridge University Press.
Abstract: In many of the studies reviewed in this book, eavesdropping takes the
following form: a subject has the opportunity to monitor, or eavesdrop upon, an interaction between two other animals,Aand B. The subject then uses the information obtained through these observations to assess A`s and B`s relative dominance or attractiveness as a mate (e.g. Mennill et al., 2002; Ch. 2). For example, Oliveira et al. (1998) found that male fighting fish Betta splendens that had witnessed two other males involved in an aggressive interaction subsequently responded more strongly to the loser of that interaction than the winner. Subjects-behaviour could not have been influenced by any inherent differences between the two males, because subjects responded equally strongly to the winner and the loser of competitive interactions they had not observed. Similarly, Peake et al. (2001) presented male great tits Parus major with the opportunity to monitor an apparent competitive interaction between two strangers by simulating a singing contest using two loudspeakers. The relative timing of the singing bouts (as measured by the degree of overlap between the two songs) provided information about each “contestants” relative status. Following the singing interaction, one of the “contestants” was introduced into the male`s territory. Males responded significantly less strongly to singers that had apparently just “lost” the interaction (see also McGregor & Dabelsteen, 1996; Naguib et al., 1999; Ch. 2). What information does an individual acquire when it eavesdrops on others? In theory, an eavesdropper could acquire information of many different sorts: about A, about B, about the relationship between A and B, or about the place of Animal Communication Networks, ed. Peter K. McGregor. Published by Cambridge University Press. c. Cambridge University Press 2005. 583 P1: JZZ/... P2: JZZ/... 0521823617c25.xml CU1917B/McGregor 0 521 582361 7 October 7, 2004 22:31 584 D. L. Cheney & R. M. Seyfarth A`s and B`s relationship in a larger social framework. The exact information acquired will probably reflect the particular species social structure. For example, songbirds like great tits live in communities in which six or seven neighbours surround each territory-holding male. Males appear to benefit from the knowledge that certain individuals occupy specific areas (e.g. Brooks & Falls, 1975), that competitive interactions between two different neighbours have particular outcomes, and that these outcomes are stable over time. We would, therefore, expect an eavesdropping great tit not only to learn that neighbour A was dominant to neighbour B, for example, but also to form the expectation that A was likely to defeat B in all future encounters. More speculatively, because the outcome of territorial interactions are often site specific (reviewed by Bradbury & Vehrencamp, 1998), we would expect eavesdropping tits to learn further that A dominates B in some areas but B dominates A in others. In contrast, the information gained from monitoring neighbours interactions would unlikely be sufficient to allow the eavesdropper to rank all of its neighbours in a linear dominance hierarchy, because not all neighbouring males would come into contact with one another. Such information would be difficult if not impossible to acquire; it might also be of little functional value. In contrast, species that live in large, permanent social groups have a much greater opportunity to monitor the social interactions of many different individuals simultaneously. Monkey species such as baboons Papio cynocephalus, for example, typically live in groups of 80 or more individuals, which include several matrilineal families arranged in a stable, linear dominance rank order (Silk et al., 1999). Offspring assume ranks similar to those of their mothers, and females maintain close bonds with their matrilineal kin throughout their lives. Cutting across these stable long-term relationships based on rank and kinship are more transient bonds: for example, the temporary associations formed between unrelated females whose infants are of similar ages, and the “friendships” formed between adult males and lactating females as an apparent adaptation against infanticide (Palombit et al., 1997, 2001). In order to compete successfully within such groups, it would seem advantageous for individuals to recognize who outranks whom, who is closely bonded to whom, and who is likely to be allied to whom (Harcourt, 1988, 1992; Cheney & Seyfarth, 1990; see below). The ability to adopt a third party`s perspective and discriminate among the social relationships that exist among others would seem to be of great selective benefit. In this chapter, we review evidence for eavesdropping in selected primate species and we consider what sort of information is acquired when one individual observes or listens in on the interactions of others. We then compare eavesdropping by primates with eavesdropping in other animal species, focusing on both potential differences and directions for further research |
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Naguib, M., Amrhein, V., & Kunc, H. P. (2004). Effects of territorial intrusions on eavesdropping neighbors: communication networks in nightingales. Behav. Ecol., 15(6), 1011–1015.
Abstract: Animal communication often occurs in communication networks in which multiple signalers and receivers are within signaling range of each other. In such networks, individuals can obtain information on the quality and motivation of territorial neighbors by eavesdropping on their signaling interactions. In songbirds, extracting information from interactions involving neighbors is thought to be an important factor in the evolution of strategies of territory defense. In a playback experiment with radio-tagged nightingales Luscinia megarhynchos we here demonstrate that territorial males use their familiar neighbors' performance in a vocal interaction with an unfamiliar intruder as a standard for their own response. Males were attracted by a vocal interaction between their neighbor and a simulated stranger and intruded into the neighbor's territory. The more intensely the neighbor had interacted with playback, the earlier the intrusions were made, indicating that males eavesdropped on the vocal contest involving a neighbor. However, males never intruded when we had simulated by a second playback that the intruder had retreated and sang outside the neighbor's territory. These results suggest that territorial males use their neighbors' singing behavior as an early warning system when territorial integrity is threatened. Simultaneous responses by neighboring males towards unfamiliar rivals are likely to be beneficial to the individuals in maintaining territorial integrity.
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Caro, T. M., Graham, C. M., Stoner, C. J., & Vargas, J. K. (2004). Adaptive significance of antipredator behaviour in artiodactyls. Anim. Behav., 67(2), 205–228.
Abstract: We used comparative data to test functional hypotheses for 17 antipredator behaviour patterns in artiodactyls. We examined the literature for hypotheses about auditory and visual signals, defensive behaviour and group-related antipredator behaviour in this taxon and derived a series of predictions for each hypothesis. Next, we documented occurrences of these behaviour patterns and morphological, ecological and behavioural variables for 200 species and coded them in binary format. We then pitted presence of an antipredator behaviour against presence of an independent variable for cervids, bovids and all artiodactyls together using nonparametric tests. Finally, we reanalysed the data using Maddison's (1990, Evolution, 44, 539-557) concentrated-changes tests and a consensus molecular and taxonomic phylogeny. We found evidence that snorting is both a warning signal to conspecifics and a pursuit-deterrent signal, lack of evidence that whistling alerts conspecifics and indications that foot stamping is a visual signal to warn group members. Evidence suggested that tail flagging was a signal to both conspecifics and predators, that bounding, leaping and stotting were used both as a signal and to clear obstacles and that prancing functioned similarly to foot stamping. Analyses of tail flicking, zigzagging and tacking were equivocal. We confirmed that inspection occurs in large groups, freezing enhances crypticity, and species seeking refuge in cliffs tend to be small. Entering water and attacks on predators had few correlates. Finally, group living, a putative antipredator adaptation, was associated with large body size and species living in open habitats, confirming Jarman's (1974, Behaviour, 48, 215-267) classic hypothesis. Bunching and group attack apparently deter predators. Despite limitations, comparative and systematic analyses can bolster adaptive hypotheses and raise new functional explanations for antipredator behaviour patterns in general.
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Hare, B., & Tomasello, M. (2004). Chimpanzees are more skilful in competitive than in cooperative cognitive tasks. Anim. Behav., 68(3), 571–581.
Abstract: In a series of four experiments, chimpanzees, Pan troglodytes, were given two cognitive tasks, an object choice task and a discrimination task (based on location), each in the context of either cooperation or competition. In both tasks chimpanzees performed more skilfully when competing than when cooperating, with some evidence that competition with conspecifics was especially facilitatory in the discrimination location task. This is the first study to demonstrate a facilitative cognitive effect for competition in a single experimental paradigm. We suggest that chimpanzee cognitive evolution is best understood in its socioecological context.
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Galef Jr B.G.,. (2004). Approaches to the study of traditional behaviors of free-living animals. Learn. Behav., 32, 53–61.
Abstract: I review literature on four different approaches to the study of traditions in animals: observation of free-living animals, laboratory experiment, armchair analysis, and field experiment. Because, by definition, a tradition entails social learning of some kind, it is difficult, perhaps impossible, to establish that a behavior is in fact traditional without knowledge of how it develops. Observations of free-living animals often provide strong circumstantial evidence of a tradition. However, even in the view of several researchers who have studied possibly traditional behaviors in natural populations, observation alone has not proven sufficient to show that social learning contributes to development of behaviors of interest. The relevance of laboratory experiments to the understanding of the development of behaviors in free-living animals is always open to challenge. Armchair analyses of field data can produce interesting hypotheses but cannot test them. Field experiments to determine how behaviors of interest develop in population members provide a promising way forward.
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Gajdon G.K.,, Fijn N.,, & Huber L.,. (2004). Testing social learning in a wild mountain parrot, the kea (Nestor notabilis). Learn. Behav., 32, 62–71.
Abstract: Huber, Taborsky, and Rechberger (2001) reported an experiment in which the efficiency with which captive keas opened a complex food container was increased by observation of a skilled conspecific. However, only testing social learning in free-ranging animals can demonstrate social learning in natural conditions. For that purpose, a tube-lifting paradigm was developed and tested on keas both in captivity and in Mount Cook National Park, New Zealand. The task was to remove a tube from an upright pole in order to gain access to a reward inside the tube. The top of the pole was higher than a standing kea, so that, to remove the tube, an individual had to simultaneously climb onto the pole and manipulate the tube up the pole with its bill. Because only 1 naive bird managed to remove a tube twice in 25 halfhour sessions and disappeared after success, another bird was trained to solve the task and to provide demonstrations for others. Even under such conditions, only 2 of at least 15 birds learned to remove the tube in 28 sessions. There was no indication that observer birds' use of bill and feet when exploring the tube changed as the number of observations of tube removal increased in a way that would, in principle, increase the likelihood of tube removal. The results suggest a dissociation of social learning potential as assessed in laboratory animals, and social transmission of foraging techniques in natural populations.
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Reader S.M.,. (2004). Distinguishing social and asocial learning using diffusion dynamics. Learn. Behav., 32, 90–104.
Abstract: Theoretical models predict that the cumulative number of individuals displaying a socially learned novel behavior will follow an accelerating pattern over time, whereas asocial processes have been associated with linear or decelerating functions. This raises the possibility that the shape of the diffusion curve may reveal something about the learning processes involved. If true, this would be particularly useful for identifying social transmission in observational field studies. Published data are reviewed and are found to provide limited support for this view. The use of accelerating curves as a diagnostic is challenging because (1) alternative theoretical models make similar predictions, (2) clear supporting empirical data are lacking, and (3) practical considerations frequently make accurate construction of the diffusion curve difficult.
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Griffin A.S.,. (2004). Social learning about predators: A review and prospectus. Learn. Behav., 32, 131–140.
Abstract: In comparison with social learning about food, social learning about predators has received little attention. Yet such research is of potential interest to students of animal cognition and conservation biologists. I summarize evidence for social learning about predators by fish, birds, eutherian mammals, and marsupials. I consider the proposal that this phenomenon is a case of S-S classical conditioning and suggest that evolution may have modified some of the properties of learning to accommodate for the requirements of learning socially about danger. I discuss some between-species differences in the properties of socially acquired predator avoidance and suggest that learning may be faster and more robust in species in which alarm behavior reliably predicts high predatory threat. Finally, I highlight how studies of socially acquired predator avoidance can inform the design of prerelease antipredator training programs for endangered species.
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White, D. J. (2004). Influences of social learning on mate-choice decisions. Learn. Behav., 32, 105–113.
Abstract: Evidence from both field and laboratory is consistent with the hypothesis that animals can acquire mate preferences by observing the mating behavior of others. It is difficult, however, to distinguish social learning about mates from a host of other social effects on mating that do not produce changes in preferences. Examples are drawn from laboratory studies on mate choice in female and male Japanese quail that illustrate ways in which social cues influence mating decisions. Quail of both sexes use social cues to modify their mate choices, but the sexes use the information to serve different purposes. Female quail gain preferences for males seen mating with other females, whereas males avoid females that they had observed mating with other males. This sex difference in social learning provides an example of how costs and benefits of sexual behavior can shape decision-making processes. Implications of the influence of social learning on sexual selection are briefly discussed.
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