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Munthali, S. M., & Banda, H. M. (1992). Distribution and abundance of the common ungulates of Nyika National Park. Afr. J. Ecol, 30, 203–212.
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Detmer, D. (1992). Response: of pigs and primitive notions. Between Species, 8(4), 203–208.
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Silk, J. B. (1992). Patterns of intervention in agonistic contests among male bonnet macaques. In F.B.M. and de Waal A. H. Harcourt (Ed.), Coalitions and Alliances in Humans and Other Animals (pp. 215–232). Oxford: Oxford University Press.
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Shettleworth, S. J., & Plowright, C. M. (1992). How pigeons estimate rates of prey encounter. J Exp Psychol Anim Behav Process, 18(3), 219–235.
Abstract: Pigeons were trained on operant schedules simulating successive encounters with prey items. When items were encountered on variable-interval schedules, birds were more likely to accept a poor item (long delay to food) the longer they had just searched, as if they were averaging prey density over a short memory window (Experiment 1). Responding as if the immediate future would be like the immediate past was reversed when a short search predicted a long search next time (Experiment 2). Experience with different degrees of environmental predictability appeared to change the length of the memory window (Experiment 3). The results may reflect linear waiting (Higa, Wynne, & Staddon, 1991), but they differ in some respects. The findings have implications for possible mechanisms of adjusting behavior to current reinforcement conditions.
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Povinelli DJ, & deBlois S. (1992). Young children's understanding of knowledge information in themselves and others. J. Comp. Psychol., 106, 228.
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de Waal, F. B. M. (1992). Coalitions as part of reciprocal relations in the Arnhem chimpanzee colony. In A. H. Harcourt, & F. B. M. de Waal (Eds.), Coalitions and Alliances in Humans and Other Animals (pp. 233–257). Oxford: Oxford University Press.
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Whiten, A., & Ham, R. (1992). On the nature and evolution of imitation in the animal kingdom: reappraisal of a century of research. Adv. Study Behav., 21, 239–283.
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Covalesky, M. E., Russoniello, C. R., & Malinowski, K. (1992). Effects of show-jumping performance stress on plasma cortisol and lactate concentrations and heart rate and behavior in horses. Journal of Equine Veterinary Science, 12(4), 244–251.
Abstract: Summary Effects of show jumping competition on stress levels in horses was examined. Twenty-six homes were sampled in both show and farm environments from three levels of show experience schooling, (least experience, n=11); intermediate, (moderate experience, n=6); open, (most experience, n=9). Blood samples were taken at 6 time points; 3 at the horse show and 3 at the home farm (baseline at rest, pre-schooling and post-performance over a jump course). Stress responses were assessed through comparison of the behavioral response of the horses (determined by a subjective scoring system) to plasma cortisol (F) concentrations. Physical exertion was evaluated by heart rate (HR) and plasma lactate (L) concentrations. Schooling jumpers displayed higher baseline F concentrations than open jumpers (83g±9.2 vs 46.4±10.2 ng/ml, respectively; p<.05); but not when compared to intermediate jumpers (66.2 ± 13.7 ng/ml; p>.05) at the horse show. At the farm, there were no differences in F concentrations between experience levels at a time point (p<.05). Least experienced horses displayed higher F values at rest at the show compared to the home farm. At the show, open jumpers had higher L concentrations post-exercise compared to intermediate horses (40.3±3.4 vs 25.5±4.0 mg/dL, respectively; p<.05); but were not different compared to schooling jumpers (34.8±2.0 mg/dL; p>.05). There were no differences in heart rates or behavior score between experience levels at specific time points at either the show or farm (p>.05). Low positive correlations were found between HR and F (r=.24, p<.05); HR and L (r-.48, p<.05); and HR and behavior (r=.22, p<.05). Results suggest that conditioned jumpers that have previously been exposed to horse show environments do not appear stressed during acute show-jumping competition.
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Dvoinos, G. M., Kharchenko, V. A., & Zviagnitsova, N. S. (1992). The characteristics of the helminth community in the Turkmen kulan (Equus hemionus). Parazitologiia, 26(3), 246–251.
Abstract: The helminth fauna of 24 kulans from Askaniya-Nova and Badkhyz was studied. 42 species of helminths were found, 34 of which belong to strongylids. The helminth species composition of kulan is similar to that of other species of horses. This is a result of an intensive parasite exchange in the historical past when numerous populations of different Equidae species made long seasonal migrations over steppe inter-river lands of Asia and grazed for some time on common pastures.
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Nowak, M. A., & Sigmund, K. (1992). Tit for tat in heterogeneous populations. Nature, 355, 250–253.
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