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Fragaszy, D., & Visalberghi, E. (2004). Socially biased learning in monkeys. Learn Behav, 32(1), 24–35.
Abstract: We review socially biased learning about food and problem solving in monkeys, relying especially on studies with tufted capuchin monkeys (Cebus apella) and callitrichid monkeys. Capuchin monkeys most effectively learn to solve a new problem when they can act jointly with an experienced partner in a socially tolerant setting and when the problem can be solved by direct action on an object or substrate, but they do not learn by imitation. Capuchin monkeys are motivated to eat foods, whether familiar or novel, when they are with others that are eating, regardless of what the others are eating. Thus, social bias in learning about foods is indirect and mediated by facilitation of feeding. In most respects, social biases in learning are similar in capuchins and callitrichids, except that callitrichids provide more specific behavioral cues to others about the availability and palatability of foods. Callitrichids generally are more tolerant toward group members and coordinate their activity in space and time more closely than capuchins do. These characteristics support stronger social biases in learning in callitrichids than in capuchins in some situations. On the other hand, callitrichids' more limited range of manipulative behaviors, greater neophobia, and greater sensitivity to the risk of predation restricts what these monkeys learn in comparison with capuchins. We suggest that socially biased learning is always the collective outcome of interacting physical, social, and individual factors, and that differences across populations and species in social bias in learning reflect variations in all these dimensions. Progress in understanding socially biased learning in nonhuman species will be aided by the development of appropriately detailed models of the richly interconnected processes affecting learning.
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Galef Jr B.G.,. (2004). Approaches to the study of traditional behaviors of free-living animals. Learn. Behav., 32, 53–61.
Abstract: I review literature on four different approaches to the study of traditions in animals: observation of free-living animals, laboratory experiment, armchair analysis, and field experiment. Because, by definition, a tradition entails social learning of some kind, it is difficult, perhaps impossible, to establish that a behavior is in fact traditional without knowledge of how it develops. Observations of free-living animals often provide strong circumstantial evidence of a tradition. However, even in the view of several researchers who have studied possibly traditional behaviors in natural populations, observation alone has not proven sufficient to show that social learning contributes to development of behaviors of interest. The relevance of laboratory experiments to the understanding of the development of behaviors in free-living animals is always open to challenge. Armchair analyses of field data can produce interesting hypotheses but cannot test them. Field experiments to determine how behaviors of interest develop in population members provide a promising way forward.
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Gajdon G.K.,, Fijn N.,, & Huber L.,. (2004). Testing social learning in a wild mountain parrot, the kea (Nestor notabilis). Learn. Behav., 32, 62–71.
Abstract: Huber, Taborsky, and Rechberger (2001) reported an experiment in which the efficiency with which captive keas opened a complex food container was increased by observation of a skilled conspecific. However, only testing social learning in free-ranging animals can demonstrate social learning in natural conditions. For that purpose, a tube-lifting paradigm was developed and tested on keas both in captivity and in Mount Cook National Park, New Zealand. The task was to remove a tube from an upright pole in order to gain access to a reward inside the tube. The top of the pole was higher than a standing kea, so that, to remove the tube, an individual had to simultaneously climb onto the pole and manipulate the tube up the pole with its bill. Because only 1 naive bird managed to remove a tube twice in 25 halfhour sessions and disappeared after success, another bird was trained to solve the task and to provide demonstrations for others. Even under such conditions, only 2 of at least 15 birds learned to remove the tube in 28 sessions. There was no indication that observer birds' use of bill and feet when exploring the tube changed as the number of observations of tube removal increased in a way that would, in principle, increase the likelihood of tube removal. The results suggest a dissociation of social learning potential as assessed in laboratory animals, and social transmission of foraging techniques in natural populations.
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Reader S.M.,. (2004). Distinguishing social and asocial learning using diffusion dynamics. Learn. Behav., 32, 90–104.
Abstract: Theoretical models predict that the cumulative number of individuals displaying a socially learned novel behavior will follow an accelerating pattern over time, whereas asocial processes have been associated with linear or decelerating functions. This raises the possibility that the shape of the diffusion curve may reveal something about the learning processes involved. If true, this would be particularly useful for identifying social transmission in observational field studies. Published data are reviewed and are found to provide limited support for this view. The use of accelerating curves as a diagnostic is challenging because (1) alternative theoretical models make similar predictions, (2) clear supporting empirical data are lacking, and (3) practical considerations frequently make accurate construction of the diffusion curve difficult.
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Griffin A.S.,. (2004). Social learning about predators: A review and prospectus. Learn. Behav., 32, 131–140.
Abstract: In comparison with social learning about food, social learning about predators has received little attention. Yet such research is of potential interest to students of animal cognition and conservation biologists. I summarize evidence for social learning about predators by fish, birds, eutherian mammals, and marsupials. I consider the proposal that this phenomenon is a case of S-S classical conditioning and suggest that evolution may have modified some of the properties of learning to accommodate for the requirements of learning socially about danger. I discuss some between-species differences in the properties of socially acquired predator avoidance and suggest that learning may be faster and more robust in species in which alarm behavior reliably predicts high predatory threat. Finally, I highlight how studies of socially acquired predator avoidance can inform the design of prerelease antipredator training programs for endangered species.
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White, D. J. (2004). Influences of social learning on mate-choice decisions. Learn. Behav., 32, 105–113.
Abstract: Evidence from both field and laboratory is consistent with the hypothesis that animals can acquire mate preferences by observing the mating behavior of others. It is difficult, however, to distinguish social learning about mates from a host of other social effects on mating that do not produce changes in preferences. Examples are drawn from laboratory studies on mate choice in female and male Japanese quail that illustrate ways in which social cues influence mating decisions. Quail of both sexes use social cues to modify their mate choices, but the sexes use the information to serve different purposes. Female quail gain preferences for males seen mating with other females, whereas males avoid females that they had observed mating with other males. This sex difference in social learning provides an example of how costs and benefits of sexual behavior can shape decision-making processes. Implications of the influence of social learning on sexual selection are briefly discussed.
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Lansade, L., Bertrand, M., Boivin, X., & Bouissou, M. - F. (2004). Effects of handling at weaning on manageability and reactivity of foals. Appl. Anim. Behav. Sci., 87(1-2), 131–149.
Abstract: The horse's temperament, including its manageability and reactivity and/or fearfulness, is of importance as it can result in problems and can render horses unsuitable for inexperienced riders. Early experience, including handling during infancy, may influence the horse's adult behaviour and reduce its fear of humans and other potentially frigthening situations. In the various species studied, handling has generally been undertaken during the neonatal period. The aim of the present study was to test the effects of handling young horses around the time of weaning, a period which has been demonstrated to be effective in increasing ease of handling in cattle and goats. Sixteen Anglo-Arab foals were handled for 12 days either immediately following weaning (early handled: EH) or 21 days later (late handled: LH); eight additional non-handled foals served as controls (C). Handling consisted of haltering, gently petting all parts of the body, picking up feet and leading the foal over 120 m. During handling sessions, EH were easier to handle than LH: time taken to fit them with a halter, to pick up feet, and “walk-ratio” (time walking under constraint/total time walking) were significantly lower for EH. During subsequent tests conducted over 2 days, 4, and 7 months, as well as 10 months and to some extent 18 months after the end of handling period, EH and LH were easier to handle and less reactive than controls, although differences diminished with time. The period following weaning can therefore be qualified as an “optimal period” for handling. Some of the effects persist for at least 18 months.
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Staniar, W. B., Kronfeld, D. S., Hoffman, R. M., Wilson, J. A., & Harris, P. A. (2004). Weight prediction from linear measures of growing Thoroughbreds. Equine Vet J, 36(2), 149–154.
Abstract: REASON FOR PERFORMING STUDY: Monitoring weight of foals is a useful management practice to aid in maximising athletic potential while minimising risks associated with deviations from normal growth. OBJECTIVE: To develop predictive equations for weight, based on linear measurements of growing Thoroughbreds (TBs). METHODS: Morphometric equations predicting weight from measurements of the trunk and legs were developed from data of 153 foals. The accuracy, precision and bias of the best fitting equation were compared to published equations using a naive data set of 22 foals. RESULTS: Accuracy and precision were maximised with a broken line relating calculated volumes (V(t + l)) to measured weights. Use of the broken line is a 2 step process. V(t + l) is calculated from linear measures (m) of girth (G), carpus circumference (C), and length of body (B) and left forelimb (F). V(t + I) = ([G2 x B] + 4[C2 x F]) 4pi. If V(t + l) < 0.27 m3, weight is estimated: Weight (kg) = V(t + l) x 1093. If V(t + l) > or = 0.27 m3: Weight (kg) = V(t + l) x 984 + 24. The broken line was more accurate and precise than 3 published equations predicting the weight of young TBs. CONCLUSIONS: Estimation of weight using morphometric equations requires attention to temporal changes in body shape and density; hence, a broken line is needed. Including calculated leg volume in the broken line model is another contributing factor to improvement in predictive capability. POTENTIAL RELEVANCE: The broken line maximises its value to equine professionals through its accuracy, precision and convenience.
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Hoskin, S. O., & Gee, E. K. (2004). Feeding value of pastures for horses. N Z Vet J, 52(6), 332–341.
Abstract: The feeding value of fresh pasture grazed in situ is determined by animal performance or productivity and could be relatively easily established for growing and lactating horses. Despite this, there is a lack of published information on the relative feeding value of different pastures and forages grazed by horses in New Zealand and the world. In addition, for adult breeding or non-breeding and young or adult sport or performance horses, the definition of feeding value and its determination remain problematic. Limited information suggests that the feeding value of perennial ryegrass-based pasture in New Zealand for young growing horses is high, and growth rates for Thoroughbred horses fed solely on pasture in New Zealand are similar to those reported from the Northern Hemisphere where grain-based supplements are fed in addition to pasture or other forages. Attempts to assess the ability of fresh pastures to meet the nutrient requirements of horses are hampered by problems associated with determination of feed intake by grazing horses and lack of knowledge of the digestibility and utilisation of digested nutrients, including the relative bioavailability of macro- and micro-minerals in pasture. A further challenge for future research is to determine the effect of herbage allowance and grazing behaviour, including pasture species preferences, on voluntary feed intake by grazing horses. Grazing pasture has benefits for equine health and well-being including reduced risk of some nutrition-related disorders and reduced prevalence of stereotypic behaviour. Pastured horses have greater freedom for expression of natural behaviours including social interaction and exercise. However, grazing pasture is also associated with animal health problems, particularly parasitism and diseases related to pasture-associated toxins.
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Millspaugh, J. J., Brundige, G. C., Gitzen, R. A., & Raedeke, K. J. (2004). Herd organization of cow elk in Custer State Park, South Dakota. Wildl Soc Bull, 32(2), 506–514.
Abstract: nderstanding herd organization is important when considering management alternatives designed to benefit or manipulate elk (Cervus elaphus) populations. We studied the seasonal and annual herd organization of cow elk in Custer State Park, South Dakota from 1993-1997 by examining seasonal subherd range size, spatial arrangement, overlap, and site fidelity. Based on social interaction analyses, we combined locations of radiocol-lared cow elk to delineate subherds. We computed 95% kernel home ranges with least-squares cross validation for each subherd by season and year. Subherd overlap and fidelity by season and year were computed using the Volume of Intersection Index (VI) statistic. We identified 5 relatively discrete, resident cow-calf subherds. We observed little overlap in utilization distributions of adjacent subherds. The mean VI score across all subherds and time points (n=140) was 0.06 (SE=0.009), indicating an average 6% overlap in subherd area utilization. Subherd overlap between pairs was 0.08 in fall (SE= 0.021), 0.06 in winter (SE=0.018), 0.06 in spring (SE=0.2), and 0.05 in summer (SE= 0.016). Range sizes were not different between any pairs of seasons or years (F13,52=0.7, P=0.75). Subherd fidelity ranged from 0.41 (SE=0.033) to 0.60 (SE=0.018) overall, indicating differential use within the subherd boundary across years. The ability to distinguish discrete cow-calf subherd units is consistent with other studies and may aid elk management in Custer State Park. However, use patterns within subherd boundaries were inconsistent across years and may reflect human disturbances (e.g., hunting and logging activities), differences in our sampling approach, or changes in matriarchal leadership. Further evaluation into factors affecting space-use patterns is necessary to predict changes in range use within the subherd boundary.
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