| Home | [1–10] << 11 12 13 14 15 16 17 18 19 20 >> [21–30] |
|
Boesch, C. (1994). Cooperative hunting in wild chimpanzees. Anim. Behav., 48(3), 653–667.
Abstract: A model for the evolution of cooperation shows that two conditions are necessary for cooperation to be stable: a hunting success rate that is low for single hunters and increases with group size, and a social mechanism limiting access to meat by non-hunters. Testing this model on TaI chimpanzees, Pan troglodytes, showed that (1) it pays for individuals to hunt in groups of three or four rather than alone or in pairs, and (2) cooperation is stable because hunters gain more at these group sizes than cheaters, owing to a meat-sharing pattern in which hunting, dominance and age, in that order, determine how much an individual gets. In addition, hunters provide cheaters (about 45% of the meat eaters) with the surplus they produce during the hunts. Thus, cooperation in Tai male chimpanzees is an evolutionarily stable strategy, and its success allows cheating to be an evolutionarily stable strategy for Tai female chimpanzees. In Gombe chimpanzees, cooperation is not stable, first, because hunting success is very high for single hunters, and second, because no social mechanism exists that limits access to meat by non-hunters. The analysis showed that some assumptions made when discussing cooperation in other social hunters might be wrong. This might downgrade our general perception of the importance of cooperation as an evolutionary cause of sociality.
|
|
Manson, J. H. (1994). Male aggression: a cost of female mate choice in Cayo Santiago rhesus macaques. Anim. Behav., 48, 473–475.
|
|
Petit, O., & Thierry, B. (1994). Aggressive and peaceful interventions in conflicts in Tonkean macaques. Anim. Behav., 48(6), 1427–1436.
Abstract: Abstract. Peaceful interventions in conflicts are an extremely rare phenomenon in most primate species. In contrast to aggressive interventions, they cannot lead to gains in terms of competition. To clarify the function and origin of this behaviour, the patterning and consequences of peaceful and aggressive interventions were studied in a semi-free ranging group of tonkean macaques, Macaca tonkeana. Intense conflicts frequently elicited both types of intervention. Interveners preferentially targeted the initiator of the conflict, who was generally the dominant of the two opponents. Males tended to intervene more than females, especially using peaceful interventions. Interventions were frequently performed on behalf of the most closely kin-related opponent; this was true particularly for aggressive interventions. In peaceful interventions, the intervener was usually dominant over both parties. Lipsmacking, clasping, mounting and social play were mainly used, and were successful in halting aggression. Peaceful interventions were frequently followed by an affinitive interaction, such as grooming, between intervener and target. Peaceful interventions thus appear to protect the beneficiary while preserving the social relationship between intervener and target. The origin of the behaviour can be traced to the epigenetic constraints arising from the species-specific social organization.
|
|
Godin, J. - G. J., & Dugatkin, L. A. (1995). Variability and repeatability of female mating preference in the guppy. Anim. Behav., 49(6), 1427–1433.
Abstract: Models of inter-sexual selection generally assume heritable variation in mating preferences among females within populations. However, little is known about the nature of such variation. The aim of this study was to characterize quantitatively the phenotypic variation in female preference for a sexually selected male trait, body colour pattern, within a population of the Trinidadian guppy, Poecilia reticulata. Significantly more female guppies preferred the more brightly coloured of two similar-sized males presented simultaneously as potential mates. Mating preference scores for individual females were significantly and positively correlated between two repeated trials on successive days. Females were thus individually consistent in their particular choice of mates, and the calculated repeatability of their mating preference was relatively high. Notwithstanding the aforementioned, significant variation existed among females in the degree of their preference for brightly coloured males. Individual mating preference scores were not normally distributed, but were rather skewed to the right (i.e. towards greater values). These results suggest that additive genetic variation for mating preferences based on male colour pattern is maintained, and the opportunity for the further evolution of both bright male colour patterns and female preference for this trait appears to exist in the study population from the Quare River, Trinidad.
|
|
Coussi-Korbel, S., & Fragaszy, D. M. (1995). On the relation between social dynamics and social learning. Anim. Behav., 50(6), 1441–1453.
Abstract: Experimental studies on social learning in animals have commonly centred on the psychological processes responsible for learning, and neglected social processes as potential influences on both the likelihood of social learning and the type of information that can be acquired socially. A model relating social learning to social dynamics among members of a group is presented. Three key hypotheses of the model are (1) behavioural coordination in time and/or space supports the process of social learning; (2) different kinds of coordination differentially support acquisition of different kinds of information; and (3) the various forms of behavioural coordination will be differentially affected by social dynamics. Several predictions relating inter-individual and group differences in social dynamics to social learning that follow from these hypotheses are presented.
|
|
Nicol, C. J. (1995). The social transmission of information and behaviour. Appl. Anim. Behav. Sci., 44(2-4), 79–98.
Abstract: Social influences on established behaviour and on the acquisition of new information and behaviour are reviewed. Distinctions between social facilitation and contagious behaviour are drawn and suggestions for further research on contagious behaviour are made. Socially derived visual, olfactory and auditory cues are considered as important influences on behaviour and subsequent learning. The evidence supporting two potential mechanisms of social learning, i.e. stimulus enhancement followed by individual learning, and imitation, is reviewed in detail. It is argued that the functions of social learning are similarly heterogeneous and include motor skill acquisition, gathering of environmental information, and social conformity. Factors affecting the spread of socially acquired skills, including the social relationship between demonstrator and observer, are highlighted. Lastly, the few studies of social learning that have been conducted with domestic species are reviewed and potential applied goals that could stimulate further research in this area are suggested.
|
|
Galef,, Bennett G. (1995). Why behaviour patterns that animals learn socially are locally adaptive. Anim. Behav., 49(5), 1325–1334.
Abstract: Recent models of the social transmission of behaviour by animals have repeatedly led their authors to the counterintuitive (and counterfactual) conclusion that traditional behaviour patterns in animals are often not locally adaptive. This deduction results from the assumption in such models that frequency of expression of socially learned behaviour patterns is not affected by rewards or punishments contingent upon their expression. An alternative approach to analysis of social learning processes, based on Staddon-Simmelhag's conditioning model, is proposed here. It is assumed that social interactions affect the probability of introduction of novel behaviour patterns into a naive individual's repertoire and that consequences of engaging in a socially learned behaviour determine whether that behaviour continues to be expressed. Review of several recently analysed instances of animal social learning suggests that distinguishing processes that introduce behaviour patterns into the repertoires of individuals from processes that select among behavioural alternatives aids in understanding observed differences in the longevity of various traditional behaviour patterns studied in both laboratory and field. Finally, implications of the present approach for understanding the role of social learning in evolutionary process are discussed.
|
|
Byrnl, R. W., & Tomasello, M. (1995). Do rats ape? Anim. Behav., 50(5), 1417–1420.
|
|
Heyes, C. M. (1995). Imitation and flattery: a reply to Byrne & Tomasello. Anim. Behav., 50(5), 1421–1424.
|
|
McDonnell, S. M., & Haviland, J. C. S. (1995). Agonistic ethogram of the equid bachelor band. Appl. Anim. Behav. Sci., 43(3), 147–188.
Abstract: An ethogram of agonistic and related behaviors among equid bachelor band members was developed. Several key English-language studies on equids were reviewed to derive a preliminary inventory of specific behaviors to be included in the ethogram. A bachelor band of domestic pony stallions pastured together was observed for approximately 50 daylight hours to obtain detailed descriptions of each behavior, enable photographic and video documentation of behaviors, and identify any behaviors to be added to the preliminary inventory. An initial draft of the ethogram was sent to 65 equine researchers for review. Twenty-eight critical reviews were received and their suggestions considered for the final draft. A total of 49 elemental behaviors including five distinct vocalizations was included in the ethogram. Three complex behavioral sequences were also included. Most of the behaviors catalogued from the direct observation of pastured pony stallions were also found in the equid literature. For many, references to these behaviors specifically among males or bachelor band members were not found. The results offer a practical tool for quantitative research and other studies of equid inter-male behavior as well as for teaching of equid behavior, and should facilitate progress toward development of a complete ethogram for the horse and other equids.
|