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Dalin, G., Magnusson, L. E., & Thafvelin, B. C. (1985). Retrospective study of hindquarter asymmetry in Standardbred trotters and its correlation with performance. Equine Vet. J., 17, 292–296.
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Fiske, J. C., & Potter, G. D. (1979). Discrimination reversal learning in yearling horses. J. Anim. Sci., 49(2), 583–588.
Abstract: Twenty-six yearling horses were tested on a serial reversal learning discrimination combining spatial and brightness cues. An original discrimination of rewarded or nonrewarded stimuli was made followed by 20 daily reversals for position/brightness discrimination. Learning criteria were defined as 11 out of 12 correct, with the last eight responses all correct. Each horse was allowed 30 trials per discrimination to achieve criteria. Mean errors (ME) and mean trials (MT) required to achieve criteria were computed for each horse. A relative learning ability index (LAI) was calculated by the formula 1000/MT/ME. A daily emotionality score, based on a scale of one (tranquil) to six (very excitable) was assigned each horse each day after testing and a mean computed for each horse. A single subjective trainability score, based on a scale of one (difficult to train) to six (easy to train) was obtained for each horse from an independent trainer. Linear regression analyses for all 26 horses revealed a reduction in MT and ME (P<.01) over the 21-day test period indicating evidence of learning to learn. Differences (P<.05) were evident between sexes for MT and ME. Significant correlations between trainability scores and learning ability indices MT, ME, and LAI were evident for colts and geldings but not for fillies. Pooled data showed significant correlations between ME and trainability. There was a negative correlation (P<.05) between emotionality and trainability scores for all 26 horses, although the filly group did not exhibit significant correlation between these parameters.
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McCall, C. A., Potter, G. D., Friend, T. H., & Ingram, R. S. (1981). Learning abilities in yearling horses using the Hebb-Williams closed field maze. J. Anim. Sci., 53(4), 928–933.
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Gaunitz, C., Fages, A., Hanghøj, K., Albrechtsen, A., Khan, N., Schubert, M., et al. (2018). Ancient genomes revisit the ancestry of domestic and Przewalski's horses. Science, 360(6384), 111–114.
Abstract: The Eneolithic Botai culture of the Central Asian steppes provides the earliest archaeological evidence for horse husbandry, ~5,500 ya, but the exact nature of early horse domestication remains controversial. We generated 42 ancient horse genomes, including 20 from Botai. Compared to 46 published ancient and modern horse genomes, our data indicate that Przewalski's horses are the feral descendants of horses herded at Botai and not truly wild horses. All domestic horses dated from ~4,000 ya to present only show ~2.7% of Botai-related ancestry. This indicates that a massive genomic turnover underpins the expansion of the horse stock that gave rise to modern domesticates, which coincides with large-scale human population expansions during the Early Bronze Age.
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McLean, I. G., Schmitt, N. T., Jarman, P. J., Duncan, C., & Wynne, C. D. L. (2000). Learning For Life: Training Marsupials To Recognise Introduced Predators. Behaviour, 137(10), 1361–1376.
Abstract: Raising endangered species in captivity for reintroduction necessarily results in animals that lack appropriate skills for coping with problems to be faced in the wild, such as predators. Using classical conditioning techniques involving linking fear of a live dog with the image of a fox, we demonstrate an adjusted fear response for two wallaby species (rufous bettongs Aepyprymnus rufescens, quokkas Setonix brachyurus). No differences in response to the fox were found for wild-caught and captive-born bettongs, even though wild-caught subjects were likely to have encountered canids prior to capture. Attempts to condition a fear response by quokkas to an odour were unsuccessful. An attempt to induce fear of the stuffed fox by linking to fear of humans in quokkas was unsuccessful, but quokkas generalised from fear of the dog to fear of the fox, despite a delay of several weeks. Trained dogs offer a valuable and ethically acceptable mechanism for improving the ability of captive-reared (or sequestered) animals to recognise and cope with predators.
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Bonabeau, E., Theraulaz, G., & Deneubourg, J. - L. (1999). Dominance orders in animal societies: the selforganization. Bull Math Biol, 61(4). Retrieved June 18, 2024, from http://dx.doi.org/10.1006/bulm.1999.0108
Abstract: In previous papers (Theraulaz et al. 1995, Bonabeau et al. 1996) we suggested, following Hogeweg and Hesper (1983, 1985), that the formation of dominance orders in animal societies could result from a selforganizing process involving a double reinforcement mechanism: winners reinforce their probability of winning and losers reinforce their probability of losing. This assumption, and subsequent models, were based on empirical data on primitively eusocial wasps (Polistes dominulus). By...
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Dugatkin, L. A., & Godin, G. J. (1992). Predator inspection, shoaling and foraging under predation hazard in the Trinidadian guppy,Poecilia reticulata. Environmental Biology of Fishes, 34(3), 265–276.
Abstract: Guppies,Poecilia reticulata, living in stream pools in Trinidad, West Indies, approached a potential fish predator (a cichlid fish model) in a tentative, saltatory manner, mainly as singletons or in pairs. Such behavior is referred to as predator inspection behavior. Inspectors approached the trunk and tail of the predator model more frequently, more closely and in larger groups than they approached the predator's head, which is presumably the most dangerous area around the predator. However, guppies were not observed in significantly larger shoals in the stream when the predator model was present. In a stream enclosure, guppies inspected the predator model more frequently when it was stationary compared to when it was moving, and made closer inspections to the posterior regions of the predator than to its head. Therefore, the guppies apparently regarded the predator model as a potential threat and modified their behavior accordingly when inspecting it. Guppies exhibited a lower feeding rate in the presence of the predator, suggesting a trade-off between foraging gains and safety against predation. Our results further suggest that predator inspection behavior may account for some of this reduction in foraging. These findings are discussed in the context of the benefits and costs of predator inspection behavior.
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Dugatkin, L. A., & Godin, J. - G. J. (1993). Female mate copying in the guppy (Poecilia reticulata): age-dependent effects. Behav. Ecol., 4(4), 289–292.
Abstract: Virtually all studies of mate choice to date have assumed that females choose mates independent of one another. Social cues, however, such as the mate choice of conspecifics, may also play an important role in such decisions. Previous work has shown that female guppies of similar age copy each other's choice of mates. Here we examine the effect of relative age on mate choice copying in the guppy, Poecilia reticulata, and examine whether younger individuals are more likely to copy the mate choice of older conspecifics than vice versa. Results indicate that younger females copy the mate choice of older females, but older individuals do not appear to be influenced by the mate choice of younger individuals.
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Syme, G. J., Pollard, J. S., Syme, L. A., & Reid, R. M. (1974). An analysis of the limited access measure of social dominance in rats.22(2), 486–500.
Abstract: The limited access situation in which only one of two or more subjects can gain access to a reward during a restricted time-period is an accepted measure of dominance in the rat. This study attempts to validate the technique by establishing the relationship between individual and competitive performance in order to determine whether `priority of access' has been measured. The generality of the competitive orders is examined by altering the competitive response while retaining the same reward. In view of the data collected for both time and weight-gain measures in food and water competition it is doubtful whether the limited access competitive technique can be considered a valid measure of dominance for the laboratory rat.
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Syme, G. J. (1974). Competitive orders as measures of social dominance.22(Part 4), 931–940.
Abstract: The use of competitive orders as measures of social dominance is examined, the conclusion being that such use is based on the assumption of the unidimensionality of social dominance. Evidence is presented to show that this is not always the case. Consequently it is suggested that each competitive order must be validated in terms of its measurement of priority of access and response requirements (internal validity) as well as its generality (external validity) before it can be regarded as a dominance measure. Problems of the validity of aggression orders as measures of social dominance are also examined along with their relationship to competitive orders.
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