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Huff, A. N. (1988). Safety. Journal of Equine Veterinary Science, 8(1), 81.
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Bednarz, J. C. (1988). Cooperative Hunting Harris' Hawks (Parabuteo unicinctus). Science, 239(4847), 1525–1527.
Abstract: Coordinated hunting by several individuals directed toward the capture and sharing of one Large prey animal has been documented convincingly only for a few mammalian carnivores. In New Mexico, Harris' hawks formed hunting parties of two to six individuals in the nonbreeding season. This behavior improved capture success and the average energy available per individual enabled hawks to dispatch prey larger than themselves. These patterns suggest that cooperation is important to understanding the evolution of complex social behavior in higher vertebrates and, specifically, that benefits derived from team hunting a key factor in the social living of Harris' hawks.
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Cheney, D. L., & Seyfarth, R. M. (1988). Social and non.social knowledge in vervet monkeys. In Machiavellian Intelligence (pp. 255–270). Oxford: Oxford Univ Press.
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Dasser V. (1988). Mapping social concepts in monkeys. In Machiavellian Intelligence (pp. 85–93). Oxford: Oxford Univ Press.
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Hauser M.D. (1988). Invention and social transmission: new data from wild vervet monkeys. In Machiavellian Intelligence (pp. 327–343). Oxford: Oxford Univ Press.
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McCann, J. S., Heird, J. C., Bell, R. W., & Lutherer, L. O. (1988). Normal and more highly reactive horses. II. The effect of handling and reserpine on the cardiac response to stimuli. Appl. Anim. Behav. Sci., 19(3-4), 215–226.
Abstract: A split-plot experiment evaluated the effect of handling and reserpine on the autonomic heart-rate response of yearling horses to various stimuli. The emotionality levels of 32 Quarter-Horse yearlings were rated by 4 experienced horsemen on a scale from 1 to 4 (1 = most nervous and erratic disposition; 4=quiet disposition). The yearlings were subsequently classified and penned based on their emotionality level; normal or nervous. Within each emotionality group, one-half the yearlings were handled daily for 14 days and the other one-half remained free in the pens. Following the handling treatment, every yearling was individually exposed to a series of stimuli, while the heart rate was monitored via a radio-telemetry system. A second treatment, reserpine, was subsequently given intramuscularly (0.005 mg/kg body weight) to one-half the yearlings of each treatment combination of emotionality and handling. The heart rate of the yearlings to the same series of stimuli previously employed was determined at 24 and 120 h and 16 days following the reserpine injection. Summarizing the results, the handled yearlings tended to exhibit lower heart rates with the handling stimulus, but the heart rate with a more novel stimulus was not affected by the previous handling treatment. Reserpine tended to suppress the heart rate of the unhandled group during the presence of a handler, but the permanency of this effect was not evident 16 days after the drug was administered. The reserpine-treated groups tended to exhibit the lowest heart-rate response to stimuli during the 120-h test-day following the administration of the drug. Heart-rate responses to the stimuli were not different between the normal and nervous yearlings.
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McCann, J. S., Heird, J. C., Bell, R. W., & Lutherer, L. O. (1988). Normal and more highly reactive horses. I. Heart rate, respiration rate and behavioral observations. Appl. Anim. Behav. Sci., 19(3-4), 201–214.
Abstract: Thirty-two Quarter horse yearlings were utilized in a split-plot experiment to establish behavioral tendencies for two levels of emotionality; normal and a more highly reactive level of emotionality termed nervous. Four observers who were experienced with horses scored the yearlings on an emotionality scale from 1 to 4, with 1 representing the highly nervous yearlings and 4 representing the quiet yearlings. Emotionality evaluations were based upon the response of the yearlings to a standard regimen of standing in a chute, being identified and being released from the chute. The inter-rater reliability coefficients were 0.90 for the normal yearlings and 0.65 for the nervous yearlings, indicating that the raters agreed less when evaluating the nervous yearlings. Yearling heart rates in the chute were correlated (r = -0.54, P<0.002) with the average emotionality score. Observational data on behavior collected 2 days following the emotionality scoring procedure indicated that the normal yearlings maintained a greater (P<0.001) individual distance than the nervous yearlings. From an activity summary, the normal yearlings spent 10.9% of the time lying down (LD), 79.1% standing (S), 9.6% walking or trotting (WT) and 0.4% of the time cantering or galloping (CG). The nervous yearlings spent 5.7% of the observational periods LD, 79.2% S, 11.7% WT and 3.4% CG. The nervous yearlings tended to have a higher overall activity index level than did the normal yearlings. Results indicate horses of different emotionality levels exhibited different behavioral patterns.
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Hayes, K. (1988). Temperament tip-offs. Horse and Rider, 11, 47–84.
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Clutton-Brock, T. H., Green, D., Hiraiwa-Hasegawa, M., & Albon, S. D. (1988). Passing the buck: resource defence, lek breeding and mate choice in fallow deer. Behav. Ecol. Sociobiol., 23, 281–296.
Abstract: lsquoLekrsquo breeding systems, where males defend small, clustered mating territories, are thought to occur where the distribution of females is heavily clumped but males are unable to defend resources used by females. In this paper, we describe a breeding system in fallow deer where males are able to defend resources used by females but the most successful bucks instead defend small territories on a traditional mating ground; where the lek is sited in an area not heavily used by females at other times of year and is visited primarily by females in or close to oestrus; and where mating success on the lek is related to territory position and to male phenotype but not to the resources available on different lek territories. Comparisons with other ungulates suggest that lek breeding species fall into two groups: those where leks are regularly visited by herds of females many of which are not in oestrus and those, like fallow deer, where leks are visited primarily by oestrous females. In the latter species, it is unlikely that females visit the lek for ecological reasons.
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Leonard, M. L., Horn, A. G., & Eden, S. F. (1988). Parent-offspring aggression in moorhens. Behav. Ecol. Sociobiol., 23, 265–270.
Abstract: The purpose of this study was to explain parental aggression to offspring in the moorhen (Gallinula chloropus). Males and females did not feed different subsets of chicks. In addition, there was a positive correlation between feeding rates of each parent to a particular chick and the number of attacks (tousles) directed to that chick, contrary to what was expected if aggression served to divide the brood. In moorhens, large chicks outcompeted small chicks for parental feedings. However, adults were more aggressive to large chicks and as a result small chicks spent significantly more time closer to parents and received more feedings than large chicks. In 84% of broods every chick was attacked at least once, although large chicks were attacked more often than small chicks. The behaviour of chicks changed immediately after an attack (Table 2). Before an attack chicks were <1 m from the parents while after an attack they were >1 m. The apparent effect of parental aggression in moorhens is to reduce demands by chicks for feedings. Aggression appears to reduce sibling competition and to encourage chick independence.
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