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Murray, M. G., & Brown, D. (1993). Niche Separation of Grazing Ungulates in the Serengeti: An Experimental Test. T. J. Anim. Ecol., 62(2), 380–389.
Abstract: 1. The niche separation of three species of alcelaphine antelope (wildebeest, topi and hartebeest) with similar body size was compared by measuring bite weight, bite rate, intake rate and selectivity of tame animals in plots containing grass at different growth stages. 2. On growing swards, hartebeest had a smaller bite weight and lower intake rate, and were also less selective of green leaf, than either topi or wildebeest. On senescent swards, hartebeest were more selective of leaf than the other two species. 3. Wildebeest had a faster bite rate than either topi or hartebeest on swards with low biomass and high protein content of green leaf (green flush). Bite weight and intake rate of wildebeest and topi were similar despite the difference in breadth of their incisor rows. 4. Topi were significantly more selective of green leaf than the other two species and were the only species to maintain a rapid bite rate on swards with high green leaf biomass. 5. The feeding experiments did not reveal significant cross-overs between species in the rate of food intake on different grass types, but each species was most proficient either in leaf selection or bite rate when feeding on grass swards in a particular growth stage. We suggest that growth stage is a primary determinant of niche separation. 6. In Serengeti, grazing ungulates which migrate are specialists of the earlier growth stages of grass which tend to be transient, while those that are residential specialize on late growth stages which are more enduring. The mobility of species, and the spatial and temporal dynamics of pastures containing different growth stages of grass, contribute to niche separation.
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Negi, G. C. S., Rikhari, H. C., Ram, J., & Singh, S. P. (1993). Foraging Niche Characteristics of Horses, Sheep and Goats in an Alpine Meadow of the Indian Central Himalaya. J. Appl. Ecol, 30(3), 383–394.
Abstract: 1. Data on plant species foraged, foraging hours, bite rate, bite size and species dry matter (DM) removed per species per bite were collected in tussock grass-forb (Grass-F), forb-tussock grass (Forb-G), Trachydium-forb (Forb), Rhododendron-Cassiope and early successional communities from May to September in a moderately foraged Central Himalayan alpine meadow in order to study the foraging niche characteristics of horses, sheep and goats. 2. The three animals together grazed 30 plant species, of which 20 were grazed by horses, 22 by sheep and 16 by goats. 3. The average foraging hours (5.2-13.2), bites per minute (23-51) and mg DM per bite (59-99) for horses, sheep and goats were significantly different in different communities and months. 4. The foraging search cost, reckoned as distance walked per unit DM eaten, was highest for goats (15.4 km kg$^{-1}$), followed by sheep (8.1 km kg$^{-1}$) and horses (1.2 km kg$^{-1}$). 5. Of the total intake of horses (3.25 kg DM day$^{-1}$), the Forb community alone accounted for 40%. Sheep (0.74 kg DM day$^{-1}$) resembled horses in this respect. In contrast, the contribution of this community was negligible in the diet of goats in which the Grass-F community contributed most to the intake. 6. Forbs were the largest dietary category for all animal species. The selection ratio varied from 0.7 to 11.3 for forbs, 1.0 to 7.2 for sedges and 1.1 to 2.5 for grasses. 7. Response breadth (in terms of species grazed) was similar for horses and sheep (0.46 vs. 0.43) and somewhat wider for goats (0.49). 8. Grazing pressures below the carrying capacity of the community appeared to favour botanical diversity.
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Petherick, J. C., Seawright, E., & Waddington, D. (1993). Influence of motivational state on choice of food or a dustbathing/foraging substrate by domestic hens. Behav. Process., 28(3), 209–220.
Abstract: Domestic hens were trained to run a Y-maze and make an association between differently coloured doorways and access to food pellets or sand. The hens were tested for their choice of doorway when the goals were not visible from the choice point and when they were food or sand deprived. Hens made the choice appropriate to their deprivation state (correct choice) significantly more often for food than sand and were faster at choosing and entering the goal box when food deprived. In a follow up experiment, the goals were visible from the choice point. Again the hens chose correctly significantly more often when food than sand deprived and made the choice and entered the goal box faster when food deprived. Thus, failure to choose sand in the first experiment was not due to an inability to learn the association, but appears to result from a strong motivation to feed in the Y-maze, even when not food deprived, and a weak motivation to dustbathe or forage, even when sand deprived.
Keywords: Food; Learning; Litter; Motivation; Poultry; Preference
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McCall, C. A., Salters, M. A., & Simpson, S. M. (1993). Relationship between number of conditioning trials per training session and avoidance learning in horses. Appl. Anim. Behav. Sci., 36(4), 291–299.
Abstract: Sixteen horses were used to determine if number of trials given per training session (5, 10, 15 or 20) affected learning performance in an avoidance conditioning task. The horse had to move from one side of a test pen to the other during an auditory cue presentation to avoid aversive stimulation. A pen 8 mx3.6 m, divided into two equal sections by a 13-cm diameter plastic pipe lying on the ground, was used as the test pen. Painted plywood panels were fastened to the fence in half the pen to help horses distinguish visually between the two parts. A 10-s auditory cue was used as a signal for horses to move from one side of the test pen to the other. A 20-s intertrial interval was used. Training sessions were conducted every third day. Each trial was recorded as an avoidance (the horse completed the task during auditory cue presentation and avoided aversive stimulus) or an error (the horse received aversive stimulus). After completing ten consecutive avoidances (criterion), the horse was removed from the study. Numbers of training sessions, trials, avoidances and errors until reaching criterion were recorded for each horse. Horses varied greatly within these variables with ranges of 3-18 sessions, 37-121 trials, 20-68 avoidances and 17-53 errors to criterion. No differences were detected (P>0.05) in the number of conditioning trials per training session (treatment) for the mean number of trials, avoidances or errors to criterion. Number of training sessions to criterion differed (P<0.01) among treatments, indicating that an optimum number of learning trials per training session might exist. Mean sessions to criterion for horses receiving 5, 10, 15 and 20 trials per session were 15.1+/-1.3, 5.8+/-1.1, 5.3+/-1.1 and 4.6+/-1.1, respectively. Regression analysis indicated that 16.2 trials per training session would minimize number of sessions to criterion. Although it is widely assumed that learning efficiency in horses is decreased when intense activity is concentrated into a small number of sessions, these results indicate that moderate repetition of training activities is needed for efficient learning.
Keywords: Horse; Learning; Avoidance conditioning
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Mal, M. E., McCall, C. A., Newland, C., & Cummins, K. A. (1993). Evaluation of a one-trial learning apparatus to test learning ability in weanling horses. Appl. Anim. Behav. Sci., 35(4), 305–311.
Abstract: Fourteen Arabian foals were used to determine if a one-trial appetitive conditioning task, developed for laboratory rats, could be adapted for use in equine learning research. The learning apparatus consisted of a 1.5 m x 0.6 m wooden grid containing 40 compartments. Seven foals received a complete learning test which consisted of placing a foal in a pen with the learning apparatus on one wall, recording the foal's behavior for 5 min and then placing a food reinforcer in a target compartment (TC). After location of the food, the foal's behavior was recorded for an additional 5 min. Total visits made to the apparatus and compartments visited by the foal were recorded. The remaining seven foals received a test in which no reinforcer was placed in the TC. These foals were re-tested the next day with reinforcement. After location of the food reinforcer, all foals exhibited more visits to the apparatus, visits to the TC, visits one compartment from the TC, and visits greater than one and less than or equal to two compartments from the TC (P<0.05). Mean distance of visits from the TC decreased after location of the reinforcer (P<0.05). Increased frequency of visits to the apparatus and concentration of visits around the TC after finding the reinforcer suggest that foals had learned the location of the reinforcer. Results suggest that a one-trial appetitive conditioning test may be applicable in equine learning research.
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Barton, R. A., & Whiten, A. (1993). Feeding competition among female olive baboons, Papio anubis. Anim. Behav., 46(4), 777–789.
Abstract: Abstract. Competition for food is thought to play a key role in the social organization of group-living female primates, leading to the prediction that individual foraging success will be partly regulated by dominance relationships. Among adult females in a group of free-ranging olive baboons, dominance rank was significantly correlated with nutrient acquisition rates (feeding rates and daily intakes), but not with dietary diversity or quality, nor with activity budgets. The mean daily food intake of the three highest-ranking females was 30% greater than that of the three lowest-ranking females, providing an explanation for relationships between female rank and fertility found in a number of other studies of group-living primates. The intensity of feeding competition, as measured by supplant rates and spatial clustering of individuals, increased during the dry season, a period of low food availability, seemingly because foods eaten then were more clumped in distribution than those eaten in the wet season. Implications for models of female social structure and maximum group size are discussed.
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Barton, R. A. (1993). Sociospatial mechanisms of feeding competition in female olive baboons, Papio anubis. Anim. Behav., 46(4), 791–802.
Abstract: Abstract. Social and spatial mechanisms of feeding competition among adult female olive baboons were studied in two free-ranging groups, one foraging for natural foods, and one that was being provisioned. Similar behavioural processes were found to underlie rank-related differences in food intake in the two situations. Dominance rank of females in the naturally foraging group was positively correlated with the rate at which other animals were supplanted from feeding sites, the ratio of supplants of others to supplants received, and the number of near neighbours while feeding on clumped foods. It is unlikely that the latter result was due to rank-related differences in matriline size, because no significant correlations between rank and neighbour density were found for non-feeding activities. Step-wise regression analysis indicated that both number of neighbours and the supplant ratio explained significant proportions of inter-individual variance in daily food intake, though only the supplant ratio contributed significantly to feeding rate. High-ranking females also had priority of access to feeding sites within trees, and competition was most intense for foods that were spatially clumped. Similarly, in the provisioned group, rank was correlated with the rate at which supplants were received, and with spatial indices estimating centrality and the area of unoccupied space around an individual. Over 99% of the inter-individual variance in feeding rate was explained in a step-wise regression with supplant rates and spatial indices as independent variables. It is concluded that both active supplanting and individuals' spatial positions within the group mediate rank-related differences in food intake.
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Veissier, I. (1993). Observational learning in cattle. Appl. Anim. Behav. Sci., 35(3), 235–243.
Abstract: Four experiments were designed to find evidence of observational learning in cattle. The experiments were run on ten experimental heifers, each observing a demonstrator mate performing a task, and on ten control heifers, each observing a non-demonstrator mate. The mates and observers were separated by wire netting in Experiments 1-3, but were in the same room in Experiment 4. The task to be learned was to push a panel to get food into a box. All naive animals were able to observe while their mate performed the task. The observers in Experiments 1 and 4 were Salers heifers that had no prior experience of the testing room; those in Experiment 2 were Salers heifers that were accustomed to the room; those in Experiment 3 were Aubrac or Limousin heifers that had already eaten in the room.
The behaviour of the observers was influenced by their mates: activity at or near the boxes was enhanced by the presence of demonstrators in Experiment 2 (box contacts: 38.0 +/- 16.2 vs. 22.1 +/- 11.9 for experimental and control heifers, respectively; P<0.05), while activity in other parts of the room in Experiment 3 was enhanced when non-demonstrator mates were present (wall sniffing: 5.4 +/- 13.9 vs. 13.9 +/- 13.7; P<0.05). Overall, 26 experimental heifers vs. 19 controls learned the task (P>0.05). The time spent eating was longer when the observer only had visual contact with a demonstrator (Experiment 1: 15.9 +/- 1.6 vs. 11.6 +/- 1.8 min), but was lower when physical contacts with the demonstrator were possible (Experiment 4: 4.6 +/- 8.8 vs. 5.4 +/- 2.2 min; P<0.05). Ten out of the 11 Limousin heifers learned the task, compared with only three out of the nine Aubrac heifers (P<0.05). The latter spent more time near the door and sniffed the walls more often than the former (2.0 +/- 1.9 vs. 0.4 +/- 0.6 min, P<0.05, and 18.1 +/- 13.4 vs. 2.7 +/- 6.5 min, P<0.01), as though they were trying to flee the situation. When animals observed a demonstrator, their attention was drawn to stimuli involved in the task but acquisition of knowledge was not greatly improved. |
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Mendoza, S. P., & Mason, W. A. (Eds.). (1993). Primate Social Conflict.
Abstract: This book examines conflict as a normal and recurrent feature of primate social life, emphasizing that the study of aggression and social conflict is important to understanding the basic processes that contribute to social order. The authors go well beyond the usual view which tends to equate social conflict with fights over food, mates, or social supremacy, and analyze the diverse manifestations and significance of conflict in a variety of case studies. Contributors are scientists with field and laboratory experience in anthropology, behavioral endocrinology, ethology, and psychology. Utilizing the growing body of research on life-span development in primatology, the authors offer more extensive analyses of the complexity of primate social relationships.
“I like the idea of social conflict as opposed to aggression as such. Too much of the focus on conflict has been on aggressive behavior, which is probably the most striking behavior observed in the field. The fact that conflict does not lead to aggression in all cases, that conflict is generally followed by some sort of reconciliation, and the consequences for fitness and future social life are important topics with respect to non-human primate society that should have considerable relevance to thinking about human social conflict.” -- Charles T. Snowdon, University of Wisconsin, Madison William A. Mason is Research Scientist at the California Regional Primate Research Center and Professor Emeritus of Psychology at the University of California. Sally P. Mendoza is Associate Professor of Psychology and Research Scientist at the California Regional Primate Research Center. 1. Primate Social Conflict: An Overview of Sources, Forms, and Consequences William A. Mason and Sally P. Mendoza 2. The Nature of Social Conflict: A Psycho-Ethological Perspective William A. Mason 3. The Evolution of Social Conflict among Female Primates Joan B. Silk 4. Social Conflict on First Encounters Sally P. Mendoza 5. Reconciliation among Primates: A Review of Empirical Evidence and Theoretical Issues Frans B. M. de Waal 6. Social Conflict in Adult Male Relationships in a Free-Ranging Group of Japanese Monkeys Naosuke Itoigawa 7. The Physiology of Dominance in Stable versus Unstable Social Hierarchies Robert M. Sapolsky 8. Temperament and Mother-Infant Conflict in Macaques: A Transactional Analysis William A. Mason, D.D. Long, and Sally P. Mendoza 9. Impact on Foraging Demands on Conflict within Mother-Infants Dyads Michael W. Andrews, Gayle Sunderland, and Leonard A. Rosenblum 10. Coordination and Conflict in Callicebus Social Groups Charles R. Menzel 11. Social Conflict in Two Monogamous New World Primates: Pairs and Rivals Gustl Anzenberger 12. Social Conflict and Reproductive Suppression in Marmoset and Tamarin Monkeys David H. Abbott 13. Biological Antecedents of Human Aggression Lionel Tiger 14. Conflict as a Constructive Force in Social Life David M. Lyons Index |
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Mulder, R. A., & Langmore, N. E. (1993). Dominant males punish helpers for temporary defection in superb fairy-wrens. Anim. Behav., 45, 830–833.
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