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Westergaard, G. C., Liv, C., Rocca, A. M., Cleveland, A., & Suomi, S. J. (2004). Tufted capuchins (Cebus apella) attribute value to foods and tools during voluntary exchanges with humans. Anim. Cogn., 7(1), 19–24.
Abstract: This research examined exchange and value attribution in tufted capuchin monkeys ( Cebus apella). We presented subjects with opportunities to obtain various foods and a tool from an experimenter in exchange for the foods or tool in the subjects' possession. The times elapsed before the first chow biscuits were expelled and/or an exchange took place were recorded as the dependent measures. Laboratory chow biscuits, grapes, apples, and a metal bolt (a tool used to probe for syrup) were used as experimental stimuli. The subjects demonstrated the ability to recognize that exchanges could occur when an experimenter was present with a desirable food. Results indicate that subjects exhibited significant variation in their willingness to barter based upon the types of foods that were both in their possession and presented by the experimenter. Subjects more readily traded chow biscuits for fruit, and more readily traded apples for grapes than grapes for apples. During the exchange of tools and food, the subjects preferred the following in descending order when the probing apparatus was baited with sweet syrup: grapes, metal bolts, and chow biscuits. However when the apparatus was not baited, the values changed to the following in descending order: grapes, chow, and metal bolts. These results indicate that tufted capuchins recognize opportunities to exchange and engage in a simple barter system whereby low-valued foods are readily traded for more highly valued food. Furthermore, these capuchins demonstrate that their value for a tool changes depending upon its utility.
Keywords: Animals; Cebus/*physiology; *Food; Humans; *Object Attachment; *Social Behavior
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Fujita, K., Kuroshima, H., & Masuda, T. (2002). Do tufted capuchin monkeys (Cebus apella) spontaneously deceive opponents? A preliminary analysis of an experimental food-competition contest between monkeys. Anim. Cogn., 5(1), 19–25.
Abstract: A new laboratory procedure which allows the study of deceptive behavior in nonhuman primates is described. Pairs of tufted capuchin monkeys faced each other in a food-competition contest. Two feeder boxes were placed between the monkeys. A piece of food was placed in one of the boxes. The subordinate individual was able to see the food and to open the box to obtain the bait. A dominant male was unable to see the food or to open the box but was able to take the food once the box was opened by the subordinate. In experiment 1, two of four subordinate monkeys spontaneously started to open the unbaited box first with increasing frequency. Experiment 2 confirmed that this “deceptive” act was not due to a drop in the rate of reinforcement caused by the usurping dominant male, under the situation in which food sometimes automatically dropped from the opened box. In experiment 3, two subordinate monkeys were rerun in the same situation as experiment 1. One of them showed some recovery of the “deceptive” act but the other did not; instead the latter tended to position himself on the side where there was no food before he started to open the box. Although the results do not clearly indicate spontaneous deception, we suggest that operationally defined spontaneous deceptive behaviors in monkeys can be analyzed with experimental procedures such as those used here.
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Forbes, A. B. (1993). A review of regional and temporal use of avermectins in cattle and horses worldwide. Vet Parasitol, 48(1-4), 19–28.
Abstract: Ivermectin and abamectin are two members of the group of parasiticides known as the avermectins; ivermectin was first registered as an injectable treatment for cattle in 1981. Since then, abamectin has been registered for cattle and ivermectin for horses. The relative popularity of the avermectins amongst farmers and veterinarians can be attributed to their spectrum of activity, convenience, wide margin of safety and the improved health and performance of stock following their use. Patterns of use in grazing animals apply equally to the avermectins as to other antiparasitics, particularly anthelmintics; these are based on a knowledge of epidemiology integrated with practical management considerations. For cattle, programs are commonly aimed at control of abomasal nematodes of the genera Ostertagia and Haemonchus. Use of avermectins is largely strategic in cattle, treatments being favored at the end of the period of transmission of these parasites; this frequently coincides with housing, entry into a feedlot or movement to another pasture. Simultaneous control of important ectoparasites at this time is an added benefit. Prophylactic use of avermectins at pasture is primarily targeted at the young first season grazing animal. In horses, a bimonthly treatment schedule during the period of risk has proved effective in helping prevent adverse effects of the main target parasites, including large and small strongyles and stomach bots. These patterns of use can be applied to the evaluation of the potential for avermectin residues in feces to have impact on pasture ecology. The evidence presented suggests that any effects are temporally and spatially limited. After more than a decade of practical use, there is no indication that avermectins have had a significant impact on pasture ecology and the environment.
Keywords: Animals; Anthelmintics/therapeutic use; Arthropods; Cattle; Cattle Diseases/drug therapy/*prevention & control; Ectoparasitic Infestations/drug therapy/prevention & control/veterinary; Horse Diseases/drug therapy/*prevention & control; Horses; Insecticides; Ivermectin/*analogs & derivatives/*therapeutic use; Nematode Infections/drug therapy/prevention & control/veterinary; Parasitic Diseases/drug therapy/prevention & control; *Parasitic Diseases, Animal
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Hawkes, J., Hedges, M., Daniluk, P., Hintz, H. F., & Schryver, H. F. (1985). Feed preferences of ponies. Equine Vet J, 17(1), 20–22.
Abstract: Preference trials were conducted with mature ponies. In Trial 1, oats were compared with oats plus sucrose. Four of six pony geldings selected oats plus sucrose, but one pony demonstrated a dislike for sucrose and one selected from the bucket on the right side regardless of content. Oats, maize, barley, rye and wheat were compared in Trial 2 using six mature pony mares. Oats were the preferred grain, with maize and barley ranking second and third respectively. Wheat and rye were the least preferred. Even though the ponies demonstrated preference, the total intake at a given meal was not greatly depressed when only the less palatable grains were fed. In Trial 3, pony mares selected a diet containing 20 per cent dried distillers' grain and 80 per cent of a basal mixed diet of maize, oats, wheat bran, soybean meal, limestone and molasses over 100 per cent basal mixed diet, but selected the basal diet over diets containing 20 per cent blood meal, beet pulp or meat and bone meal and 80 per cent basal diet. They did not differentiate against diets containing 20 per cent alfalfa meal or 10 or 5 per cent meat and bone meal when the diets were compared to the basal mixed diet.
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Lonon, A. M., & Zentall, T. R. (1999). Transfer of value from S+ to S- in simultaneous discriminations in humans. Am J Psychol, 112(1), 21–39.
Abstract: When animals learn a simultaneous discrimination, some of the value of the positive stimulus (S+) appears to transfer to the negative stimulus (S-). The present experiments demonstrate that such value transfer can also be found in humans. In Experiment 1 humans were trained on 2 simple simultaneous discriminations, the first between a highly positive stimulus, A (1,000 points); and a negative stimulus, B (0 points); and the second between a less positive stimulus, C (100 points); and a negative stimulus, D (0 points). On test trials, most participants preferred B over D. In Experiments 2 and 3 the value of the 2 original discriminations was equated in training (A[100]B[0] and C[100]D[0]). In Experiment 2 the values of the positive stimuli were then altered (A[1,000]C[0]); again, most participants preferred B over D. In Experiment 3, however, when the values of B and D were altered (B[1,000]D[0]), participants were indifferent to A and C. Thus, the mechanism that underlies value transfer in humans appears to be related to Pavlovian second-order conditioning. Similar mechanisms may be involved in assimilation processes in social contexts.
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Dunbar, R. I. M. (2007). Male and female brain evolution is subject to contrasting selection pressures in primates. BMC Biol, 5, 21.
Abstract: The claim that differences in brain size across primate species has mainly been driven by the demands of sociality (the “social brain” hypothesis) is now widely accepted. Some of the evidence to support this comes from the fact that species that live in large social groups have larger brains, and in particular larger neocortices. Lindenfors and colleagues (BMC Biology 5:20) add significantly to our appreciation of this process by showing that there are striking differences between the two sexes in the social mechanisms and brain units involved. Female sociality (which is more affiliative) is related most closely to neocortex volume, but male sociality (which is more competitive and combative) is more closely related to subcortical units (notably those associated with emotional responses). Thus different brain units have responded to different selection pressures.
Keywords: Animals; *Brain/physiology; *Evolution; Female; Humans; Male; *Selection (Genetics); *Sex Characteristics
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Kiltie, R. A., Fan, J., & Laine, A. F. (1995). A wavelet-based metric for visual texture discrimination with applications in evolutionary ecology. Math Biosci, 126(1), 21–39.
Abstract: Much work on natural and sexual selection is concerned with the conspicuousness of visual patterns (textures) on animal and plant surfaces. Previous attempts by evolutionary biologists to quantify apparency of such textures have involved subjective estimates of conspicuousness or statistical analyses based on transect samples. We present a method based on wavelet analysis that avoids subjectivity and that uses more of the information in image textures than transects do. Like the human visual system for texture discrimination, and probably like that of other vertebrates, this method is based on localized analysis of orientation and frequency components of the patterns composing visual textures. As examples of the metric's utility, we present analyses of crypsis for tigers, zebras, and peppered moth morphs.
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Clark, G. G., & Hibler, C. P. (1973). Horse flies and Elaeophora schneideri in the Gila National Forest, New Mexico. J Wildl Dis, 9(1), 21–25.
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Marino, L. (2002). Convergence of complex cognitive abilities in cetaceans and primates. Brain Behav Evol, 59(1-2), 21–32.
Abstract: What examples of convergence in higher-level complex cognitive characteristics exist in the animal kingdom? In this paper I will provide evidence that convergent intelligence has occurred in two distantly related mammalian taxa. One of these is the order Cetacea (dolphins, whales and porpoises) and the other is our own order Primates, and in particular the suborder anthropoid primates (monkeys, apes, and humans). Despite a deep evolutionary divergence, adaptation to physically dissimilar environments, and very different neuroanatomical organization, some primates and cetaceans show striking convergence in social behavior, artificial 'language' comprehension, and self-recognition ability. Taken together, these findings have important implications for understanding the generality and specificity of those processes that underlie cognition in different species and the nature of the evolution of intelligence.
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Freire, R., Wilkins, L. J., Short, F., & Nicol, C. J. (2003). Behaviour and welfare of individual laying hens in a non-cage system. Br Poult Sci, 44(1), 22–29.
Abstract: 1. A leg band containing a transponder was fitted to 80 birds in a perchery containing 1,000 birds. 2. The transponder emitted a unique identification number when a bird walked on one of 8 flat antennae on the floor. The recording apparatus was used to measure the amount of time that each of the tagged birds spent on the slatted and littered areas in a 6-week period. 3. Some birds spent long periods of time on the slats, possibly as a means of avoiding repeated attacks. Duration on the slats was greatest in birds with the worst (as opposed to better) feather scores of the head, back and tail regions. 4. Birds that spent long periods on the slats were lighter than other birds at both 39 weeks of age and 72 weeks of age and had greater back, head and tail feather damage, consistent with these birds being victims of pecking. 5. Tagged birds received a social avoidance test outside the perchery at 39 weeks of age, which suggested that birds retreated to the slats in response to pecks rather than just to close proximity to other birds. 6. The failure to find that duration on the slats was related to anatomical indicators of stress (liver, spleen and bursa of Fabricius) suggests that retreating to the slats following pecking attenuates physiological stress responses. 7. We conclude that the provision of areas where birds in a large group can avoid pecking may improve the welfare of a minority of victimised birds.
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