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Mayes, E., & Duncan, P. (1986). Temporal patterns of feeding behaviour in free-ranging horses. Behav., 96, 105–129.
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McClearn, G. E. (1971). Behavioral genetics. Behav Sci, 16(1), 64–81.
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McDonald, D. (2009). Young-boy networks without kin clusters in a lek-mating manakin. Behav. Ecol. Sociobiol., 63(7), 1029-1034.
Abstract: I use 10 years of data from a long-term study of lek-mating long-tailed manakins to relate the social network among males to their spatial and genetic structure. Previously, I showed that the network connectivity of young males predicts their future success. Here, I ask whether kinship might shape the organization of this young-boy network . Not surprisingly, males that were more socially distant (linked by longer network paths) were affiliated with perch zones (lek arenas) that were further apart. Relatedness (r) among males within the network decreased as social distance increased, as might be expected under kin selection. Nevertheless, any role for indirect inclusive fitness benefits is refuted by the slightly negative mean relatedness among males at all social distances within the network (overall mean r = -0.06). That is, relatedness ranged from slightly negative (-0.04) to more negative (-0.2). In contrast, relatedness in dyads for which at least one of the males was outside the social network (involving at least one blood-sampled male not documented to have interacted with other banded males) was slightly above the random expectation (mean r = 0.05). The slight variations around r = 0 among males of different categories likely reflect dispersal dynamics, rather than any influence of kinship on social organization. Relatedness did not covary with the age difference between males. These results, together with previous results for lack of relatedness between alpha and beta male partners, refute any role for kin selection in the evolution of cooperative display in this lek-mating system.
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McGreevy, P. D. (2004).
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McGreevy, P. D., Harman, A., McLean, A., & Hawson, L. (2010). Over-flexing the horse's neck: A modern equestrian obsession? Journal of Veterinary Behavior: Clinical Applications and Research, 5(4), 180–186.
Abstract: We used an opportunistic review of photographs of different adult and juvenile horses walking, trotting, and cantering (n = 828) to compare the angle of the nasal plane relative to vertical in feral and domestic horses at liberty (n = 450) with ridden horses advertised in a popular Australian horse magazine (n = 378). We assumed that horses in advertisements were shown at, what was perceived by the vendors to be, their best. Of the ridden horses, 68% had their nasal plane behind the vertical. The mean angle of the unridden horses at walk, trot, and canter (30.7 ± 11.5; 27.3 ± 12.0; 25.5 ± 11.0) was significantly greater than those of the ridden horses (1.4 ± 14.1; ?5.1 ± ?11.1; 3.1 ± 15.4, P < 0.001). Surprisingly, unridden domestic horses showed greater angles than feral horses or domestic horses at liberty. We compared adult and juvenile horses in all 3 gaits and found no significant difference. Taken together, these findings demonstrate that the longitudinal neck flexion of the degree desirable by popular opinion in ridden horses is not a common feature of unridden horses moving naturally. Moreover, they suggest that advertised horses in our series are generally being ridden at odds with their natural carriage and contrary to the international rules of dressage (as published by the International Equestrian Federation). These findings are discussed against the backdrop of the established doctrine, which states that carrying a rider necessitates changes in longitudinal flexion, and in the context of the current debate around hyperflexion.
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McGreevy, P. D., & McLean, A. N. (2009). Punishment in horse-training and the concept of ethical equitation. J. Vet. Behav., 4(5), 193–197.
Abstract: By definition, punishment makes a response less likely in the future. Because horses are largely trained by negative reinforcement, they are susceptible to inadvertent punishment. Delays in the release of pressure can make desirable responses less likely and thus punish them. This study examines the correct use of negative reinforcement and identifies a continuum between poorly timed negative reinforcement and punishment. It explores some of the problems of non-contingent punishment and the prospect of learned helplessness and experimental neurosis. It concludes by introducing the concept of ethical equitation.
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McGreevy, P. D., & McLean, A. N. (2007). Roles of learning theory and ethology in equitation. Journal of Veterinary Behavior: Clinical Applications and Research, 2(4), 108–118.
Abstract: By definition, ethology is primarily the scientific study of animal behavior, especially as it occurs in a natural environment; applied ethology being the study of animal behavior in the human domain. The terms equine ethology and ethological training are becoming commonplace in the equestrian domain, yet they seem to be used with a conspicuous lack of clarity and with no mention of learning theory. Most of what we do to train horses runs counter to their innate preferences. This article summarizes the ethological challenges encountered by working horses and considers the merits and limitations of ethological solutions. It also questions the use of terms such as “alpha” and “leader” and examines aspects of learning theory, equine cognition, and ethology as applied to horse training and clinical behavior modification. We propose 7 training principles that optimally account for the horse's ethological and learning abilities and maintain maximal responsivity in the trained horse. These principles can be summarized as: (1) use learning theory appropriately; (2) train easy-to-discriminate signals; (3) train and subsequently elicit responses singularly; (4) train only one response per signal; (5) train all responses to be initiated and subsequently completed within a consistent structure; (6) train persistence of current operantly conditioned responses; and (7) avoid and disassociate flight responses. Adherence to these principles and incorporating them into all horse training methodologies should accelerate training success, reduce behavioral wastage of horses, and improve safety for both humans and horses.
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Mendl M, H. Z. Living in gourps: Evolutionary Perspective. In Social Behavior in Farm Animals.
Abstract: An understanding of social behavior is increasingly necessary in farm animal husbandry as more animals are housed in groups rather than in individual stalls or pens. There may be economic or welfare reasons for such housing. This book is the first to specifically address this important subject. The chapters fall into three broad subject areas: concepts in social behavior; species specific chapters; current issues. Authors include leading experts from Europe, North America, Australia and New Zealand.
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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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Milgram, N. W., Head, E., Muggenburg, B., Holowachuk, D., Murphey, H., Estrada, J., et al. (2002). Landmark discrimination learning in the dog: effects of age, an antioxidant fortified food, and cognitive strategy. Neurosci Biobehav Rev, 26(6), 679–695.
Abstract: The landmark discrimination learning test can be used to assess the ability to utilize allocentric spatial information to locate targets. The present experiments examined the role of various factors on performance of a landmark discrimination learning task in beagle dogs. Experiments 1 and 2 looked at the effects of age and food composition. Experiments 3 and 4 were aimed at characterizing the cognitive strategies used in performance on this task and in long-term retention. Cognitively equivalent groups of old and young dogs were placed into either a test group maintained on food enriched with a broad-spectrum of antioxidants and mitochondrial cofactors, or a control group maintained on a complete and balanced food formulated for adult dogs. Following a wash-in period, the dogs were tested on a series of problems, in which reward was obtained when the animal responded selectively to the object closest to a thin wooden block, which served as a landmark. In Experiment 1, dogs were first trained to respond to a landmark placed directly on top of coaster, landmark 0 (L0). In the next phase of testing, the landmark was moved at successively greater distances (1, 4 or 10 cm) away from the reward object. Learning varied as a function of age group, food group, and task. The young dogs learned all of the tasks more quickly than the old dogs. The aged dogs on the enriched food learned L0 significantly more rapidly than aged dogs on control food. A higher proportion of dogs on the enriched food learned the task, when the distance was increased to 1cm. Experiment 2 showed that accuracy decreased with increased distance between the reward object and landmark, and this effect was greater in old animals. Experiment 3 showed stability of performance, despite using a novel landmark, and new locations, indicating that dogs learned the landmark concept. Experiment 4 found age impaired long-term retention of the landmark task. These results indicate that allocentric spatial learning is impaired in an age-dependent manner in dogs, and that age also affects performance when the distance between the landmark and target is increased. In addition, these results both support a role of oxidative damage in the development of age-associated cognitive dysfunction and indicate that short-term administration of a food enriched with supplemental antioxidants and mitochondrial cofactors can partially reverse the deleterious effects of aging on cognition.
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