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Zentall, T.R. |
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Title |
Action imitation in birds |
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Journal Article |
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Year |
2004 |
Publication |
Learning & behavior : a Psychonomic Society publication |
Abbreviated Journal |
Learn Behav |
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Volume |
32 |
Issue |
1 |
Pages |
15-23 |
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Keywords |
Adaptation, Psychological; Animals; *Birds; *Imitative Behavior; Imprinting (Psychology); *Learning; Motivation; Psychological Theory; *Social Environment; *Social Facilitation; Vocalization, Animal |
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Abstract |
Action imitation, once thought to be a behavior almost exclusively limited to humans and the great apes, surprisingly also has been found in a number of bird species. Because imitation has been viewed by some psychologists as a form of intelligent behavior, there has been interest in how it is distributed among animal species. Although the mechanisms responsible for action imitation are not clear, we are now at least beginning to understand the conditions under which it occurs. In this article, I try to identify and differentiate the various forms of socially influenced behavior (species-typical social reactions, social effects on motivation, social effects on perception, socially influenced learning, and action imitation) and explain why it is important to differentiate imitation from other forms of social influence. I also examine some of the variables that appear to be involved in the occurrence of imitation. Finally, I speculate about why a number of bird species, but few mammal species, appear to imitate. |
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Department of Psychology, University of Kentucky, Lexington, Kentucky 40506, USA. zentall@uky.edu |
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1543-4494 |
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PMID:15161137 |
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Call Number |
refbase @ user @ |
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230 |
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Overli, O.; Korzan, W.J.; Hoglund, E.; Winberg, S.; Bollig, H.; Watt, M.; Forster, G.L.; Barton, B.A.; OVerli, E.; Renner, K.J.; Summers, C.H. |
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Title |
Stress coping style predicts aggression and social dominance in rainbow trout |
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Journal Article |
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Year |
2004 |
Publication |
Hormones and Behavior |
Abbreviated Journal |
Horm Behav |
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45 |
Issue |
4 |
Pages |
235-241 |
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Keywords |
Adaptation, Psychological/physiology; Aggression/*physiology; Animals; *Dominance-Subordination; Female; *Hierarchy, Social; Hydrocortisone/blood; Individuality; Male; Matched-Pair Analysis; Oncorhynchus mykiss/*physiology; Stress/*physiopathology |
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Social stress is frequently used as a model for studying the neuroendocrine mechanisms underlying stress-induced behavioral inhibition, depression, and fear conditioning. It has previously been shown that social subordination may result in increased glucocorticoid release and changes in brain signaling systems. However, it is still an open question which neuroendocrine and behavioral differences are causes, and which are consequences of social status. Using juvenile rainbow trout of similar size and with no apparent differences in social history, we demonstrate that the ability to win fights for social dominance can be predicted from the duration of a behavioral response to stress, in this case appetite inhibition after transfer to a new environment. Moreover, stress responsiveness in terms of confinement-induced changes in plasma cortisol was negatively correlated to aggressive behavior. Fish that exhibited lower cortisol responses to a standardized confinement test were markedly more aggressive when being placed in a dominant social position later in the study. These findings support the view that distinct behavioral-physiological stress coping styles are present in teleost fish, and these coping characteristics influence both social rank and levels of aggression. |
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Biology Department and Neuroscience Group, University of South Dakota, Vermillion, SD 57069, USA. oyvind.overli@bio.uio.no |
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0018-506X |
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PMID:15053939 |
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Equine Behaviour @ team @ |
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4192 |
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Bering, J.M. |
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A critical review of the “enculturation hypothesis”: the effects of human rearing on great ape social cognition |
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Journal Article |
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Year |
2004 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
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Volume |
7 |
Issue |
4 |
Pages |
201-212 |
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Keywords |
Animals; *Cognition; *Culture; Hominidae/*psychology; Humans; *Imitative Behavior; Imprinting (Psychology); *Intention; Macaca; Psychological Theory; Social Behavior; *Social Environment; Species Specificity |
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Numerous investigators have argued that early ontogenetic immersion in sociocultural environments facilitates cognitive developmental change in human-reared great apes more characteristic of Homo sapiens than of their own species. Such revamping of core, species-typical psychological systems might be manifest, according to this argument, in the emergence of mental representational competencies, a set of social cognitive skills theoretically consigned to humans alone. Human-reared great apes' capacity to engage in “true imitation,” in which both the means and ends of demonstrated actions are reproduced with fairly high rates of fidelity, and laboratory great apes' failure to do so, has frequently been interpreted as reflecting an emergent understanding of intentionality in the former. Although this epigenetic model of the effects of enculturation on social cognitive systems may be well-founded and theoretically justified in the biological literature, alternative models stressing behavioral as opposed to representational change have been largely overlooked. Here I review some of the controversy surrounding enculturation in great apes, and present an alternative nonmentalistic version of the enculturation hypothesis that can also account for enhanced imitative performance on object-oriented problem-solving tasks in human-reared animals. |
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Department of Psychology, University of Arkansas, Fayetteville, AR 72701, USA. jbering@uark.edu |
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1435-9448 |
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PMID:15004739 |
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Equine Behaviour @ team @ |
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2543 |
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Author |
Nelson, D.M.; Gardner, I.A.; Chiles, R.F.; Balasuriya, U.B.; Eldridge, B.F.; Scott, T.W.; Reisen, W.K.; James Maclachlan, N. |
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Title |
Prevalence of antibodies against Saint Louis encephalitis and Jamestown Canyon viruses in California horses |
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Journal Article |
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Year |
2004 |
Publication |
Comparative Immunology, Microbiology and Infectious Diseases |
Abbreviated Journal |
Comp Immunol Microbiol Infect Dis |
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27 |
Issue |
3 |
Pages |
209-215 |
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Animals; Antibodies, Viral/*blood; California/epidemiology; Encephalitis Virus, California/*immunology/isolation & purification; Encephalitis Virus, St. Louis/*immunology/isolation & purification; Encephalitis, St. Louis/epidemiology/immunology/*veterinary/virology; Female; Horse Diseases/epidemiology/immunology/*virology; Horses; Logistic Models; Male; Neutralization Tests/veterinary; Polyomavirus Infections/epidemiology/immunology/*veterinary/virology; Questionnaires; Seroepidemiologic Studies; Tumor Virus Infections/epidemiology/immunology/*veterinary/virology |
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Jamestown Canyon (JC) and Saint Louis encephalitis (SLE) viruses are mosquito-transmitted viruses that have long been present in California. The objective of this study was to determine the seroprevalence of these two viruses in horses prior to the introduction of West Nile (WN) virus. Approximately 15% of serum samples collected in 1998 from 425 horses on 44 equine operations horses throughout California had serum antibodies to JC virus, whereas antibodies were not detected to SLE virus. The results indicate that horses in California were commonly infected prior to 1998 with mosquito-transmitted Bunyaviruses that are identical or closely related to JC virus, but not with SLE virus. The different seroprevalence of SLE and JC viruses in horses likely reflects the unique ecology of each virus, and it is predicted that WN virus will have a wider distribution in California than closely related SLE virus. |
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Animal and Plant Health Inspection Service, Veterinary Services, U.S. Department of Agriculture, California and Nevada Area Office, 9850 Micron Avenue, Suite E, Sacramento, CA 95827, USA |
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0147-9571 |
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PMID:15001316 |
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Equine Behaviour @ team @ |
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2637 |
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Kirkpatrick, J.F.; Turner, A. |
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Absence of effects from immunocontraception on seasonal birth patterns and foal survival among barrier island wild horses |
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Journal Article |
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Year |
2003 |
Publication |
Journal of applied animal welfare science : JAAWS |
Abbreviated Journal |
J Appl Anim Welf Sci |
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6 |
Issue |
4 |
Pages |
301-308 |
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Animals; Animals, Newborn; Animals, Wild/*physiology; Birth Rate; Case-Control Studies; Contraception, Immunologic/methods/*veterinary; Egg Proteins/administration & dosage; Female; Horses/*physiology; Maryland/epidemiology; Membrane Glycoproteins/administration & dosage; Population Control; Pregnancy; *Receptors, Cell Surface; *Reproduction; Seasons; Vaccines, Contraceptive/administration & dosage |
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Despite a large body of safety data, concern exists that porcine zonae pellucidae (PZP) immunocontraception--used to manage wild horse populations--may cause out-of-season births with resulting foal mortality. Our study at Assateague, Maryland indicated the effects of immunocontraception on season of birth and foal survival between 1990 and 2002 on wild horses from Assateague Island. Among 91 mares never treated, 69 (75.8%) of foals were born in April, May, and June (in season). Among 77 treated mares, 50 (64.9%) were born in season. Of 29 mares foaling within 1 year after treatment (contraceptive failures), 20 (68.9%) were born in season. Of 48 mares treated for greater than 2 years then withdrawn from treatment, 30 (62.5%) of 48 foals were born in season. There were no significant differences (p <.05) between either treatment group or untreated mares. Survival did not differ significantly among foals born in or out of season or among foals born to treated or untreated mares. Data indicate a lack of effect of PZP contraception on season of birth or foal survival on barrier island habitats. |
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Science and Conservation Center Zoo Montana, Billings, Montana 59106, USA. jkirkpatrick@montana.net |
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1088-8705 |
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PMID:14965784 |
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refbase @ user @ |
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140 |
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Author |
Dubois, F.; Giraldeau, L.-A. |
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Title |
The forager's dilemma: food sharing and food defense as risk-sensitive foraging options |
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Journal Article |
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Year |
2003 |
Publication |
The American Naturalist |
Abbreviated Journal |
Am Nat |
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162 |
Issue |
6 |
Pages |
768-779 |
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Animals; Competitive Behavior/*physiology; *Environment; Feeding Behavior/*physiology; *Game Theory; *Models, Biological; Population Density; Population Dynamics |
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Although many variants of the hawk-dove game predict the frequency at which group foraging animals should compete aggressively, none of them can explain why a large number of group foraging animals share food clumps without any overt aggression. One reason for this shortcoming is that hawk-dove games typically consider only a single contest, while most group foraging situations involve opponents that interact repeatedly over discovered food clumps. The present iterated hawk-dove game predicts that in situations that are analogous to a prisoner's dilemma, animals should share the resources without aggression, provided that the number of simultaneously available food clumps is sufficiently large and the number of competitors is relatively small. However, given that the expected gain of an aggressive animal is more variable than the gain expected by nonaggressive individuals, the predicted effect of the number of food items in a clump-clump richness-depends on whether only the mean or both the mean and variability associated with payoffs are considered. More precisely, the deterministic game predicts that aggression should increase with clump richness, whereas the stochastic risk-sensitive game predicts that the frequency of encounters resulting in aggression should peak at intermediate clump richnesses or decrease with increasing clump richness if animals show sensitivity to the variance or coefficient of variation, respectively. |
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Departement des Sciences Biologiques, Universite du Quebec a Montreal, Case postale 8888, Succursale Centre-Ville, Montreal, Quebec H3C 3P8, Canada. fdubois@u-bourgogne.fr |
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0003-0147 |
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PMID:14737714 |
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2132 |
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Touma, C.; Palme, R.; Sachser, N. |
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Analyzing corticosterone metabolites in fecal samples of mice: a noninvasive technique to monitor stress hormones |
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Journal Article |
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Year |
2004 |
Publication |
Hormones and Behavior |
Abbreviated Journal |
Horm Behav |
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45 |
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1 |
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10-22 |
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Adrenal Cortex/drug effects; Adrenal Cortex Function Tests; Adrenocorticotropic Hormone/pharmacology; Analysis of Variance; Animals; Circadian Rhythm; Corticosterone/*analysis/metabolism; Dexamethasone/pharmacology; Feces/*chemistry; Female; Immunoenzyme Techniques/*methods; Male; Mice; Mice, Inbred C57BL; Models, Animal; Reproducibility of Results; Stress, Psychological/*metabolism |
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In small animals like mice, the monitoring of endocrine functions over time is constrained seriously by the adverse effects of blood sampling. Therefore, noninvasive techniques to monitor, for example, stress hormones in these animals are highly demanded in laboratory as well as in field research. The aim of our study was to evaluate the biological relevance of a recently developed technique to monitor stress hormone metabolites in fecal samples of laboratory mice. In total, six experiments were performed using six male and six female mice each. Two adrenocorticotropic hormone (ACTH) challenge tests, two dexamethasone (Dex) suppression tests and two control experiments [investigating effects of the injection procedure itself and the diurnal variation (DV) of glucocorticoids (GCs), respectively] were conducted. The experiments clearly demonstrated that pharmacological stimulation and suppression of adrenocortical activity was reflected accurately by means of corticosterone metabolite (CM) measurements in the feces of males and females. Furthermore, the technique proved sensitive enough to detect dosage-dependent effects of the ACTH/Dex treatment and facilitated to reveal profound effects of the injection procedure itself. Even the naturally occurring DV of GCs could be monitored reliably. Thus, our results confirm that measurement of fecal CM with the recently established 5alpha-pregnane-3beta,11beta,21-triol-20-one enzyme immunoassay is a very powerful tool to monitor adrenocortical activity in laboratory mice. Since mice represent the vast majority of all rodents used for research worldwide and the number of transgenic and knockout mice utilized as animal models is still increasing, this noninvasive technique can open new perspectives in biomedical and behavioral science. |
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Department of Behavioural Biology, University of Muenster, D-48149 Muenster, Germany. touma@uni-muenster.de |
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0018-506X |
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PMID:14733887 |
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Equine Behaviour @ team @ |
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4084 |
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Cerutti, D.T.; Staddon, J.E.R. |
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Immediacy versus anticipated delay in the time-left experiment: a test of the cognitive hypothesis |
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Journal Article |
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Year |
2004 |
Publication |
Journal of Experimental Psychology. Animal Behavior Processes |
Abbreviated Journal |
J Exp Psychol Anim Behav Process |
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30 |
Issue |
1 |
Pages |
45-57 |
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Animals; Choice Behavior/*physiology; Cognition/*physiology; Columbidae; Male; Models, Psychological; Psychological Theory; *Reinforcement (Psychology); *Reinforcement Schedule; Time Perception/*physiology |
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In the time-left experiment (J. Gibbon & R. M. Church, 1981), animals are said to compare an expectation of a fixed delay to food, for one choice, with a decreasing delay expectation for the other, mentally representing both upcoming time to food and the difference between current time and upcoming time (the cognitive hypothesis). The results of 2 experiments support a simpler view: that animals choose according to the immediacies of reinforcement for each response at a time signaled by available time markers (the temporal control hypothesis). It is not necessary to assume that animals can either represent or subtract representations of times to food to explain the results of the time-left experiment. |
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Department of Psychological and Brain Sciences, Duke University, Durham, NC 27708-1050, USA. cerutti@psych.duke.edu |
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0097-7403 |
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PMID:14709114 |
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Equine Behaviour @ team @ |
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2768 |
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Author |
Matsuzawa, T. |
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Title |
The Ai project: historical and ecological contexts |
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Journal Article |
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Year |
2003 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
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6 |
Issue |
4 |
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199-211 |
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Adaptation, Psychological; Animals; *Behavior, Animal; *Cognition; *Culture; Discrimination Learning; Ecology; Female; History, 20th Century; Imitative Behavior; *Learning; Male; Pan troglodytes/*psychology; Research/history |
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This paper aims to review a long-term research project exploring the chimpanzee mind within historical and ecological contexts. The Ai project began in 1978 and was directly inspired by preceding ape-language studies conducted in Western countries. However, in contrast with the latter, it has focused on the perceptual and cognitive capabilities of chimpanzees rather than communicative skills between humans and chimpanzees. In the original setting, a single chimpanzee faced a computer-controlled apparatus and performed various kinds of matching-to-sample discrimination tasks. Questions regarding the chimpanzee mind can be traced back to Wolfgang Koehler's work in the early part of the 20th century. Yet, Japan has its unique natural and cultural background: it is home to an indigenous primate species, the Japanese snow monkey. This fact has contributed to the emergence of two previous projects in the wild led by the late Kinji Imanishi and his students. First, the Koshima monkey project began in 1948 and became famous for its discovery of the cultural propagation of sweet-potato washing behavior. Second, pioneering work in Africa, starting in 1958, aimed to study great apes in their natural habitat. Thanks to the influence of these intellectual ancestors, the present author also undertook the field study of chimpanzees in the wild, focusing on tool manufacture and use. This work has demonstrated the importance of social and ecological perspectives even for the study of the mind. Combining experimental approaches with a field setting, the Ai project continues to explore cognition and behavior in chimpanzees, while its focus has shifted from the study of a single subject toward that of the community as a whole. |
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Section of Language and Intelligence, Primate Research Institute, Kyoto University, Japan. matsuzaw@pri.kyoto-u.ac.jp |
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1435-9448 |
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PMID:14566577 |
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Equine Behaviour @ team @ |
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2552 |
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Author |
Ganswindt, A.; Palme, R.; Heistermann, M.; Borragan, S.; Hodges, J.K. |
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Non-invasive assessment of adrenocortical function in the male African elephant (Loxodonta africana) and its relation to musth |
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Journal Article |
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Year |
2003 |
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General and Comparative Endocrinology |
Abbreviated Journal |
Gen Comp Endocrinol |
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Volume |
134 |
Issue |
2 |
Pages |
156-166 |
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Adrenal Cortex/*metabolism/secretion; Adrenal Cortex Function Tests/methods/*veterinary; Adrenocorticotropic Hormone/physiology; Animals; Carbon Isotopes/diagnostic use; Chromatography, High Pressure Liquid/veterinary; Elephants/*metabolism/urine; Feces/*chemistry; Glucocorticoids/analysis/urine; Hydrocortisone/*analysis/diagnostic use/urine; Immunoenzyme Techniques/methods/veterinary; Male; Reproduction/physiology; Sexual Behavior, Animal/physiology; Stress, Psychological/diagnosis/*physiopathology; Testosterone/*analysis/diagnostic use/urine |
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Abstract |
Adult male elephants periodically show the phenomenon of musth, a condition associated with increased aggressiveness, restlessness, significant weight reduction and markedly elevated androgen levels. It has been suggested that musth-related behaviours are costly and that therefore musth may represent a form of physiological stress. In order to provide data on this largely unanswered question, the first aim of this study was to evaluate different assays for non-invasive assessment of adrenocortical function in the male African elephant by (i) characterizing the metabolism and excretion of [3H]cortisol (3H-C) and [14C]testosterone (14C-T) and (ii) using this information to evaluate the specificity of four antibodies for determination of excreted cortisol metabolites, particularly with respect to possible cross-reactions with androgen metabolites, and to assess their biological validity using an ACTH challenge test. Based on the methodology established, the second objective was to provide data on fecal cortisol metabolite concentrations in bulls during the musth and non-musth condition. 3H-C (1 mCi) and 14C-T (100 microCi) were injected simultaneously into a 16 year old male and all urine and feces collected for 30 and 86 h, respectively. The majority (82%) of cortisol metabolites was excreted into the urine, whereas testosterone metabolites were mainly (57%) excreted into the feces. Almost all radioactive metabolites recovered from urine were conjugated (86% 3H-C and 97% 14C-T). In contrast, 86% and >99% of the 3H-C and 14C-T metabolites recovered from feces consisted of unconjugated forms. HPLC separations indicated the presence of various metabolites of cortisol in both urine and feces, with cortisol being abundant in hydrolysed urine, but virtually absent in feces. Although all antibodies measured substantial amounts of immunoreactivity after HPLC separation of peak radioactive samples and detected an increase in glucocorticoid output following the ACTH challenge, only two (in feces against 3alpha,11-oxo-cortisol metabolites, measured by an 11-oxo-etiocholanolone-EIA and in urine against cortisol, measured by a cortisol-EIA) did not show substantial cross-reactivity with excreted 14C-T metabolites and could provide an acceptable degree of specificity for reliable assessment of glucocorticoid output from urine and feces. Based on these findings, concentrations of immunoreactive 3alpha,11-oxo-cortisol metabolites were determined in weekly fecal samples collected from four adult bulls over periods of 11-20 months to examine whether musth is associated with increased adrenal activity. Results showed that in each male levels of these cortisol metabolites were not elevated during periods of musth, suggesting that in the African elephant musth is generally not associated with marked elevations in glucocorticoid output. Given the complex nature of musth and the variety of factors that are likely to influence its manifestation, it is clear, however, that further studies, particularly on free-ranging animals, are needed before a possible relationship between musth and adrenal function can be resolved. This study also clearly illustrates the potential problems associated with cross-reacting metabolites of gonadal steroids in EIAs measuring glucocorticoid metabolites. This has to be taken into account when selecting assays and interpreting results of glucocorticoid metabolite analysis, not only for studies in the elephant but also in other species. |
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German Primate Centre, Department of Reproductive Biology, Kellnerweg 4, 37077 Gottingen, Germany. ganswindt@www.dpz.gdwg.de |
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English |
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0016-6480 |
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PMID:14511986 |
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Equine Behaviour @ team @ |
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4085 |
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