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Kaplan, G., & Rogers, L. J. (2002). Patterns of Gazing in Orangutans (Pongo pygmaeus). Int. J. Primatol., 23(3), 501–526.
Abstract: Eyes play an important role in communication amongst humans and animals. However, relatively little is known about specific differences in eye morphology amongst primates and how these features might be associated with social structure and direction of gaze. We present a detailed study of gazing and eye morphology-exposed sclera and surrounding features in orangutans. We measured gazing in rehabilitating orangutans in two contexts: interspecific viewing of the experimenter (with video camera) and intraspecific gazing (between subjects). Our findings show that direct staring is avoided and social looking is limited to certain age/social categories: juveniles engage in more looking at other orangutans than do adults or infants. While orangutans use eye movements in social communication, they avoid the more prolonged mutual gaze that is characteristic of humans, and also apparent in chimpanzees and gorillas. Detailed frame-by-frame analysis of videotapes from field and zoo studies of orangutans revealed that they pay visual attention to both human observers and conspecifics by glancing sideways, with the head turned at an angle away from the subject being observed. Mutual gaze was extremely rare, and we have observed only two incidences of gaze following. Orangutans in captivity appear to use a more restricted pattern of gazes compared to free-living, rehabilitating ones, possibly suggesting the presence of a pathological condition (such as depression) in the captive subjects. Our findings have implications for further investigations of social communication and cognition in orangutans.
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Heyes, C. M. (2002). Transformation and associative theories of imitation. In K. Dautenhahn, & C. L. Nehaniv (Eds.), Imitation in animals and artefacts (pp. 501–523). Cambridge, MA.: MIT Press.
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McDonough, P., Kindig, C. A., Ramsel, C., Poole, D. C., & Erickson, H. H. (2002). The effect of treadmill incline on maximal oxygen uptake, gas exchange and the metabolic response to exercise in the horse. Experimental Physiology, 87(04), 499–506 M3– null.
Abstract: In healthy man, conditions that change muscle O2 delivery affect the achievable maximum rate of O2 uptake (V[dot above]O2,max) as well as the metabolic (e.g. lactate threshold, LT) and gas exchange (e.g. gas exchange threshold, Tge) responses to incremental exercise. Inclined (I) compared to level (L) running increases locomotory muscle EMG at a given speed in the horse, indicative of elevated metabolic demand. To our knowledge, the effect of treadmill incline on V[dot above]O2,max, LT and Tge has not been addressed in the exercising quadruped. We used blood sampling and breath-by-breath expired gas analysis to test the hypothesis that I (10 % gradient) would increase V[dot above]O2,max and the rate of O2 uptake (V[dot above]O2) at LT and Tge in six Thoroughbred horses during incremental running to volitional fatigue. V[dot above]O2,max was significantly higher for I (I, 77.8 ± 4.1; L, 65.5 ± 5.3 l min-1; P < 0.05), but peak plasma lactate concentration was not (I, 28.0 ± 3.7; L, 25.9 ± 3.0 mM). Arterial PCO2 increased to 62.1 ± 3.3 and 57.9 ± 2.7 Torr (I vs. L; P < 0.05), yet despite this relative hypoventilation, a distinct Tge was present. This Tge occurred at a significantly different absolute (I, 49.6 ± 3.2; L, 42.4 ± 3.2 l min-1; P < 0.05), but nearly identical relative V[dot above]O2 (I, 63.6 ± 1.2; L, 63.9 ± 1.6 % V[dot above]O2,max) in I and L. Similarly, LT occurred at a significantly greater absolute V[dot above]O2 (I, 37.3 ± 2.8; L, 26.9 ± 2.1 l min-1), but a relative V[dot above]O2 that was not different (I, 47.9 ± 2.1; L, 43.9 ± 4.5 % V[dot above]O2,max). In addition, Tge occurred at a significantly higher (P [less-than-or-equal] 0.05) absolute and relative V[dot above]O2 than LT for both I and L tests. In conclusion, V[dot above]O2,max is higher during inclined than level running and both LT and Tge in the horse occur at a similar percentage of V[dot above]O2,max irrespective of the absolute level of V[dot above]O2,max. In contrast to humans, LT is a poor analogue of Tge in the horse.
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Dugatkin, L. A. (2002). Cooperation in animals: An evolutionary overview. Biology and Philosophy, 17(4), 459–476.
Abstract: Evolutionary biologists have grappled with the question of the emergenceand maintenance of cooperation since Darwin first listed animal cooperation asapotential problem for his theory of natural selection. Here I review four pathsthat have been delineated in the study of intra-specific cooperation amonganimals. These paths – kinship, reciprocity, byproduct mutualism andgroupselection – serve as a starting point for behavioral ecologistsinterestedstudying the initiation and maintenance of cooperation. After reviewing theempirical and theoretical underpinnings of these paths to cooperation, I touchupon some recent work that has attempted to examine (or reexamine) the role ofphylogeny, punishment and morality in the light of cooperative behavior.
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Murphy, M. A., Waits, L. P., Kendall, K. C., Wasser, S. K., Higbee, J. A., & Bogden, R. (2002). An evaluation of long-term preservation methods for brown bear (Ursus arctos) faecal DNA samples. Conservat. Genet., 3(4), 435–440.
Abstract: Relatively few large-scale faecal DNA studieshave been initiated due to difficulties inamplifying low quality and quantity DNAtemplate. To improve brown bear faecal DNA PCRamplification success rates and to determinepost collection sample longevity, fivepreservation methods were evaluated: 90%ethanol, DETs buffer, silica-dried, oven-driedstored at room temperature, and oven-driedstored at -20 °C. Preservationeffectiveness was evaluated for 50 faecalsamples by PCR amplification of a mitochondrialDNA (mtDNA) locus (~146 bp) and a nuclear DNA(nDNA) locus (~200 bp) at time points of oneweek, one month, three months and six months. Preservation method and storage timesignificantly impacted mtDNA and nDNAamplification success rates. For mtDNA, allpreservation methods had >= 75% success atone week, but storage time had a significantimpact on the effectiveness of the silicapreservation method. Ethanol preserved sampleshad the highest success rates for both mtDNA(86.5%) and nDNA (84%). Nuclear DNAamplification success rates ranged from 26-88%, and storage time had a significant impacton all methods but ethanol. Preservationmethod and storage time should be importantconsiderations for researchers planningprojects utilizing faecal DNA. We recommendpreservation of faecal samples in 90% ethanolwhen feasible, although when collecting inremote field conditions or for both DNA andhormone assays a dry collection method may beadvantageous.
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Kaiser, D. H., Zentall, T. R., & Neiman, E. (2002). Timing in pigeons: effects of the similarity between intertrial interval and gap in a timing signal. J Exp Psychol Anim Behav Process, 28(4), 416–422.
Abstract: Previous research suggests that when a fixed interval is interrupted (known as the gap procedure), pigeons tend to reset memory and start timing from 0 after the gap. However, because the ambient conditions of the gap typically have been the same as during the intertrial interval (ITI), ambiguity may have resulted. In the present experiment, the authors found that when ambient conditions during the gap were similar to the ITI, pigeons tended to reset memory, but when ambient conditions during the gap were different from the ITI, pigeons tended to stop timing, retain the duration of the stimulus in memory, and add to that time when the stimulus reappeared. Thus, when the gap was unambiguous, pigeons timed accurately.
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Kurtzman H.S., Church R.M., & Crystal J.D. (2002). Data archiving for animal cognition research: Report of an NIMH workshop. Animal Learning & Behavior, 30, 405–412.
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Previc, F. H. (2002). Thyroid hormone production in chimpanzees and humans: implications for the origins of human intelligence. Am J Phys Anthropol, 118(4), 402–3; discussion 404–5.
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Broom, M., & Cannings, C. (2002). Modelling Dominance Hierarchy formation as a Multi-player game. J. Theor. Biol., 219(3), 397–413.
Abstract: Animals who live in groups need to divide available resources amongst themselves. This is often achieved by means of a dominance hierarchy, where dominant individuals obtain a larger share of the resources than subordinate individuals. This paper introduces a model of dominance hierarchy formation using a multi-player extension of the classical Hawk-Dove game. Animals play non-independent pairwise games in a Swiss tournament which pairs opponents against those which have performed equally well in the conflict so far, for a fixed number of rounds. Resources are divided according to the number of contests won. The model, and its emergent properties, are discussed in the context of experimental observations.
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Hauser MD, Santos LR, Spaepen GM, & Pearson HE. (2002). Problem solving, inhibition and domain-specific experience: experiments on cotton-top tamarins, Saguinus oedipus. Anim. Behav., 64, 387.
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