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De Vries, H., & Appleby, M. C. (2000). Finding an appropriate order for a hierarchy: a comparison of the I&SI and the BBS methods. Anim. Behav., 59(1), 239–245.
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Chase, I. D., Bartolomeo, C., & Dugatkin, L. A. (1994). Aggressive interactions and inter-contest interval: how long do winners keep winning? Anim. Behav., 48(2), 393–400.
Abstract: Abstract. Considerable evidence across many taxa demonstrates that prior social experience affects the outcome of subsequent aggressive interactions. Although the 'loser effect', in which an individual losing one encounter is likely to lose the next, is relatively well understood, studies of the 'winner effect', in which winning one encounter increases the probability of winning the next, have produced mixed results. Earlier studies differ concerning whether a winner effect exists, and if it does, how long it lasts. The variation in results, however, may arise from different inter-contest intervals and procedures for selecting contestants employed across previous studies. These methodological differences are addressed through a series of experiments using randomly selected winners and three different inter-contest intervals in the pumpkinseed sunfish, Lepomis gibbosus. The results indicate that a winner effect does in fact exist in pumpkinseed sunfish, but that it only lasts between 15 and 60 min. Based on these results, predictions about the behavioural dynamics of hierarchy formation are discussed, and it is suggested that it may be impossible, in principle, to predict the outcome of dominance interactions between some individuals before they are actually assembled to form a group. Finally, the possible mechanisms underlying the winner effect are explored.
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Becker, C. D., & Ginsberg, J. R. (1990). Mother-infant behaviour of wild Grevy's zebra: adaptations for survival in semidesert East Africa. Anim. Behav., 40(6), 1111–1118.
Abstract: Mother-infant interactions and patterns of foal behaviour in the Grevy's zebra, Equus grevyi, differe from those reported for other equids. Grevy's zebra foals exhibit longer intervals between suckling bouts, do not drink water until they are 3 months old, and reach independence from the mare sooner than other equids. Furthermore, Grevy's zebra foals advance their acquisition of adult feeding behaviour. A 6-week-old Grevy's zebra foal spends as much time feeding as a 5-month-old wild horse foal. From the time their foals are born until the foals reach an age of 3 months, females form small groups (three females and their foals). These groups are never found further than 2·0 km from surface water and are usually associated with a territorial male. Unlike other equids, the foals of which always follow their mares, when female Grevy's zebra go to drink, they leave their foals in “kindergartens”, which are guarded by a single adult animal, usually a territorial male. It is proposed that many of these differences in behaviour and rates of juvenile development are the result of adaptation to an arid environment. Water requirements during early lactation appear to influence strongly the social behaviour of the Grevy's zebra and should also be a strong influence on the mother-infant behaviour of other arid-living ungulates.
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Goldschmidt, T., Bakker, T. C. M., & Feuth-de Bruijn, E. (1993). Selective copying in mate choice of female sticklebacks. Anim. Behav., 45(3), 541–547.
Abstract: There is evidence that female three-spined sticklebacks, Gasterosteus aculeatus L., prefer to mate with males whose nests contain eggs rather than with males with empty nests. While there is consensus on this point, a dispute exists about whether this preference should be attributed to a direct effect of the eggs on the female's entering the nest or, alternatively, to a positive impact of the eggs on the courtship behaviour and breeding coloration of the male. In the field experiment reported here females strongly preferred nests with eggs over empty nests. Additionally, females were less likely to enter risky nests with eggs: nests that contained fewer eggs than one average clutch or more eggs than the average nest content of parental males in this population. However, in the field possible differences in male attractiveness were not controlled for. In supplementary laboratory experiments the effect on female choice of possible changes in male attractiveness (intensified courtship and coloration) as a result of the presence of eggs in the nest was tested. Other differences in male attractiveness as a result of differences in male quality (body size, breeding coloration before the test, territory quality and size) were controlled for. When females had no access to the nests, they showed no preference for males with eggs in their nests in simultaneous choice tests. These results, together with the earlier published data, make it likely that the preference of females for nests with eggs is partly a direct consequence of the eggs themselves. So female sticklebacks are influenced by the mate choice behaviour of other females, but remain selective as to the actual nest content.
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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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di Bitetti, M. S., & Janson, C. H. (2001). Social foraging and the finder's share in capuchin monkeys, Cebus apella. Anim. Behav., 62(1), 47–56.
Abstract: Group living can confer advantages to individuals, but it can also impose severe costs through resource competition. Kleptoparasitism is one example in which some individuals (joiners) can exploit the food discovered by other animals (finders). This type of social foraging has been modelled either as an information-sharing model or as a producer-scrounger game. An important variable in these models is the finder's advantage: the number of items obtained by the finder before the arrival of other individuals. In this study we describe how the spatial position and rank of individuals in a group of wild tufted capuchin monkeys affect their ability to discover and exploit new food sources. We also analyse the factors that affect the finder's share and the total amount of food obtained by the finder from a newly discovered resource. By placing platforms filled with bananas at novel locations in their home range, we show that animals in the leading edge of a foraging group have a higher probability of discovering new food sources than animals occupying other spatial positions. The alpha male and the alpha female, which tended to occupy central-forward positions, were able to monopolize newly discovered food sources and thus obtain a major share of them. The finder's share at the feeding platforms was smaller when there was more food on a platform, but increased with longer delays before the arrival of other individuals. The total amount of food obtained by the finder from the feeding platforms was larger when there was more food on the platform, when the finder was of higher social status, and when it took longer for other individuals to arrive. Animals can increase their finder's share and total amount consumed from a newly discovered resource by keeping large interindividual distances and by avoiding giving cues about the presence of food (such as food-associated vocalizations) to other animals.
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Campbell, F. M., Heyes, C. M., & Goldsmith, A. R. (1999). Stimulus learning and response learning by observation in the European starling, in a two-object/two-action test. Anim. Behav., 58(1), 151–158.
Abstract: Juvenile European starlings, Sturnus vulgaris , were allowed to observe a conspecific demonstrator using its beak to remove one of two distinctively coloured objects (i.e. a red or a black plug) from a hole in the lid of a plastic box. Both plugs could be removed by either pulling up on a loop of string inserted through the centre of the plug, or pushing down on the plug. When subsequently allowed access to the plugs, and rewarded with food for all removal responses, regardless of the object to which they were made and their direction, observer birds removed the same plug in the same direction as their demonstrator. These results suggest that the two-object/two-action paradigm is a valuable procedure for testing for the simultaneous effects of learning about a stimulus and a response, an object and an action, through conspecific observation.
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Campbell, F. M., & Heyes, C. M. (2002). Rats smell: odour-mediated local enhancement, in a vertical movement two-action test. Anim. Behav., 63(6), 1055–1063.
Abstract: In two experiments, hungry rats, Rattus norvegicus, were present in one side of an operant chamber while a conspecific demonstrator in the adjacent compartment moved a single lever either up or down for a food reward. During a subsequent test session, in which these rats were allowed access to the lever for the first time, all responses were rewarded regardless of their direction. In experiment 1, rats that were prevented from observing the direction of lever movement by means of a screen showed a reliable demonstrator-consistent response bias, while rats that had observed the direction of lever movement and in addition had access to any odour cues deposited on the lever did not. In experiment 2, each rat observed another rat (the `viewed' demonstrator) moving a lever either up or down. They were then transferred into the test compartment of a different operant chamber in which another rat (the `box' demonstrator) had moved the lever in the same direction as the viewed demonstrator or in the opposite direction. These observer rats showed a reliable preference for their box demonstrator's direction, but responded in the opposite direction to their viewed demonstrator. Taken together, the results of these experiments suggest that directional responding by rats in a vertical movement two-action test is influenced by demonstrator-deposited odour cues in addition to visual experience of a demonstrator's behaviour. Furthermore, while odour-mediated local enhancement gave rise to demonstrator-consistent responding, visual observation of a conspecific appeared to have the reverse effect. Copyright 2002 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved.
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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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Kenward, B., Rutz, C., Weir, A. A. S., & Kacelnik, A. (2006). Development of tool use in New Caledonian crows: inherited action patterns and social influences. Anim. Behav., 72(6), 1329–1343.
Abstract: New Caledonian crows, Corvus moneduloides, are the most advanced avian tool makers and tool users. We previously reported that captive-bred isolated New Caledonian crows spontaneously use twig tools and cut tools out of Pandanus spp. tree leaves, an activity possibly under cultural influence in the wild. However, what aspects of these behaviours are inherited and how they interact with individual and social experience remained unknown. To examine the interaction between inherited traits, individual learning and social transmission, we observed the ontogeny of twig tool use in hand-reared juveniles. Successful food retrieval was preceded by stereotyped object manipulation action patterns that resembled components of the mature behaviour, demonstrating that tool-oriented behaviours in this species are an evolved specialization. However, there was also an effect of social learning: juveniles that had received demonstrations of twig tool use by their human foster parent showed higher levels of handling and insertion of twigs than did their naive counterparts; a choice experiment showed that they preferred to handle objects that they had seen being manipulated by their human foster parent. Our observations are consistent with the hypothesis that individual learning, cultural transmission and creative problem solving all contribute to the acquisition of the tool-oriented behaviours in the wild, but inherited species-typical action patterns have a greater role than has been recognized.
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