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Maddock, L. (1995). The “migration” and grazing succession. In A. R. E. Sinclair, & A. R. E. Norton-Griffiths (Eds.), Serengeti: Dynamics of an Ecosystem. Chicago: University Of Chicago Press.
Abstract: Editorial Reviews
Book Description Originally published in 1979, Serengeti: Dynamics of an Ecosystem was immediately recognized as the first synthesis of the patterns and processes of a major ecosystem. A prototype for initial studies, Serengeti contains baseline data for further and comparative studies of ecosystems. The new Serengeti II builds on the information presented originally in Serengeti; both books together offer essential information and insights for ecology and conservation biology. |
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McGreevy, P. D., French, N. P., & Nicol, C. J. (1995). The prevalence of abnormal behaviours in dressage, eventing and endurance horses in relation to stabling. Vet. Rec., 137(2), 36–37.
Abstract: The behaviour of horses competing in different disciplines was studied and the relationship between the time they spent out of the stable and the prevalence of abnormal behaviour was examined. The owners of dressage, eventing and endurance horses were sent a questionnaire and a total of 1101 responses were received, giving data on 1750 horses. The behaviours studied were wood-chewing, weaving, crib-biting/wind-sucking and box-walking. The reported percentage prevalences of abnormal behaviour for the dressage, eventing and endurance horses were 32.5, 30.8 and 19.5, respectively. The relationship between the time spent in the stable and the prevalence of abnormal behaviour was examined by chi 2 tests which showed that there were significant linear trends for the eventing group (P < 0.001) and the dressage group (P < 0.05). It is concluded that the time a horse spends out of the stable is related to the discipline for which it is being trained and in dressage and eventing horses the time spent in a stable is correlated with an increased risk of abnormal behaviour.
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VanDierendonck, M. C., de Vries, H., & Schilder, M. B. H. (1995). An Analysis of Dominance, Its Behavioural Parameters and Possible Determinants in a Herd of Icelandic orses in Captivity. Netherl. J. Zool., 45(3-4), 362–385.
Abstract: Th e applicability of the concept of dominance was investigated in a captive herd of  Icelandic
horses and  ponies of diff erent breeds. Eight out of  behaviours possibly related to dominance occurred frequently enough to be investigated in detail. For these eight agonistic behaviours the coverage, the unidirectionality in the exchange, and the degree of transitivity (Landau`s linearity index) were calculated. Four off ensive behaviours, together with avoidance, were suitable for further analysis with regard to dominance. Th e patterns of asymmetries with which these behaviours were exchanged were suffi ciently similar as to justify the application of the dominance concept and to construct a (nearly) linear dominance hierarchy. Th e rank order of the castrated stallions was completely linear, the hierarchy of the mares was almost completely linear. Th e results suggest that off ensive and defensive aggressive behaviours should be treated separately and that the concept of dominance is applicable. However, ritualized formal dominance signals between adult horses appear to be (almost) absent. Th e rank positions of the individuals were correlated with age and residency in the herd but not with height. Middle ranking horses tended to be more frequently in the close vicinity of another horse than high ranking or low ranking horses. Over and above this correlation at the individual level, it was found that pairs of horses close in rank to each other were more often also spatially close to each other. Being in oestrus did not infl uence the dominance relationships between mares. For castrated stallions the rank positions were correlated with the age at which they were castrated. Th is suggests that in male horses experience prior to neutering infl uences the behaviour afterwards. Keywords: Dominance; rank order; horses; Icelandic horses.
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Mesterton-Gibbons, M., & Dugatkin, L. A. (1995). Toward a theory of dominance hierarchies: effects of assessment, group size, and variation in fighting ability. Behav. Ecol., 6(4), 416–423.
Abstract: We introduce assessment to the analysis of dominance hierarchies by exploring the effect of an evolutionarily stable fighting rule when there is variation in resource holding potential (RHP) and RHP is not a perfectly reliable predictor of the outcome of a fight. With assessment, the probability of a linear hierarchy decreases with group size but can remain appreciable for groups of up to seven or eight individuals, whereas it decreases virtually to zero if there is no assessment. The probability of a hierarchy that correlates perfectly with RHP is low unless group size is small.
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Dugatkin, L. A., & Hoglund, J. (1995). Delayed breeding and the evolution of mate copying in lekking species. J. Theor. Biol., 174(3), 261–267.
Abstract: Recent experimental evidence indicates that females may copy the mate choice of others. Here, we present a model for the evolution of mate copying strategies in lekking species. In the model, all females (copiers and non-copiers) assess male quality, but a copier's assessment of a male's quality increases after males have mated with other females. The model demonstrates that mate copying is favored when breeding late in the season has a relatively high cost. We hope that our results will spur empirical work quantifying the time constraints associated with breeding, thus allowing more direct tests of the model's predictions.
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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.
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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.
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Chalmeau, R., & Gallo, A. (1995). Cooperation in primates: Critical analysis of behavioural criteria. Behav. Process., 35(1-3), 101–111.
Abstract: Concerning hunting in chimpanzees, cooperation has generally been attributed to the behaviour of two or more individuals acting together to achieve a common goal (Boesch and Boesch, 1989). The common goal is often considered as the concrete result of a common action by two or several individuals. Although this result could be used as a criterion for cooperation, it could also be an outcome due to chance. We suggest that the goal, viewed as a concrete benefit shared by the partners, is not a requisite of cooperation but rather a possible consequence of a common action largely submitted to social constraints. Individuals engaged in a cooperative task in order to solve a problem have to exchange information to adjust to each other's behaviour. However, evidence of communication between partners during simultaneous cooperation is rare. An experiment in which two chimpanzees each had to simultaneously pull a handle to get a fruit was performed. We analysed not only the concrete result of the partners' activity but also what the individuals took into account before pulling a handle. We tried to specify what the chimpanzees learned by means of a series of logical propositions which we were able to confront the experimental results.
Keywords: Cognition; Communication; Cooperation; Evolution; Primates
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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.
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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.
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