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Author |
Reichmuth Kastak, C.; Schusterman, R.J. |
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Title |
Long-term memory for concepts in a California sea lion ( Zalophus californianus) |
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Journal Article |
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Year |
2002 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
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Volume |
5 |
Issue |
4 |
Pages |
225-232 |
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Keywords |
Animals; Concept Formation; Female; Memory/*physiology; Mental Processes; Sea Lions/physiology/*psychology; Time Factors |
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Abstract |
An adult California sea lion ( Zalophus californianus) with extensive experience in performing discrimination learning tasks was tested to evaluate her long-term memory for two previously learned concepts. An associative concept, that of equivalence classification, was retested after a retention interval of approximately 1 year. The sea lion had originally shown emergent equivalence classification with nonsimilarity-based classes of stimuli in a simple discrimination repeated-reversal procedure as well as in a matching-to-sample procedure. The 1-year memory test revealed no decrement in classification performance in either procedure. A relational concept, that of generalized identity matching, was retested after approximately 10 years. The sea lion had originally received trial-and-error exemplar training with identity matching-to-sample problems prior to transferring the concept to novel stimulus configurations. In the 10-year memory test, the sea lion immediately and reliably applied the previously established identity concept to familiar and novel sets of matching problems. These are the first reports of long-term conceptual memory in a nonprimate species. The experimental findings are consistent with a variety of observations of sea lions in natural settings, which indicate that natal sites, feeding areas, and individuals may be remembered over long periods of time. |
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Long Marine Laboratory, University of California at Santa Cruz, 100 Shaffer Road, Santa Cruz, CA 95060, USA. coll@cats.ucsc.edu |
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1435-9448 |
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PMID:12461600 |
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Equine Behaviour @ team @ |
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2590 |
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Author |
Fremouw, T.; Herbranson, W.T.; Shimp, C.P. |
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Title |
Dynamic shifts of pigeon local/global attention |
Type |
Journal Article |
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Year |
2002 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
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Volume |
5 |
Issue |
4 |
Pages |
233-243 |
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Keywords |
Animals; Attention/*physiology; *Behavior, Animal; Columbidae/*physiology; Male; Reaction Time; Visual Perception/*physiology |
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Abstract |
It has previously been shown that pigeons can shift attention between parts and wholes of complex stimuli composed of larger, “global” characters constructed from smaller, “local” characters. The base-rate procedure used biased target level within any condition at either the local or global level; targets were more likely at one level than at the other. Biasing of target level in this manner demonstrated shifts of local/global attention over a time span consisting of several days with a fixed base rate. Experiment 1 examined the possibility that pigeons can shift attention between local and global levels of perceptual analysis in seconds rather than days. The experiment used priming cues the color of which predicted on a trial-by-trial basis targets at different perceptual levels. The results confirmed that pigeons, like humans, can display highly dynamic stimulus-driven shifts of local/global attention. Experiment 2 changed spatial relations between features of priming cues and features of targets within a task otherwise similar to that used in experiment 1. It was predicted that this change in cues might affect asymmetry but not the occurrence of a priming effect. A priming effect was again obtained, thereby providing generality to the claim that pigeons can learn that trial-by-trial primes predict targets at different levels of perceptual analysis. Pigeons can display perceptual, stimulus-driven priming of a highly dynamic nature. |
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Department of Psychology, University of California-Berkeley, Berkeley, CA 94720-1650, USA |
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1435-9448 |
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PMID:12461601 |
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Equine Behaviour @ team @ |
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2589 |
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Milgram, N.W.; Head, E.; Muggenburg, B.; Holowachuk, D.; Murphey, H.; Estrada, J.; Ikeda-Douglas, C.J.; Zicker, S.C.; Cotman, C.W. |
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Title |
Landmark discrimination learning in the dog: effects of age, an antioxidant fortified food, and cognitive strategy |
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Journal Article |
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Year |
2002 |
Publication |
Neuroscience and Biobehavioral Reviews |
Abbreviated Journal |
Neurosci Biobehav Rev |
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Volume |
26 |
Issue |
6 |
Pages |
679-695 |
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Keywords |
Age Factors; Aging/*physiology; Analysis of Variance; Animals; Antioxidants/*pharmacology; Blood Chemical Analysis/methods; Cognition/*physiology; *Diet; Discrimination Learning/*drug effects/*physiology; Distance Perception/drug effects/physiology; Dogs/physiology; Female; Male; Psychomotor Performance/physiology; Retention (Psychology)/drug effects/physiology; Spatial Behavior/*drug effects/*physiology; Task Performance and Analysis; Time Factors; Vitamin E/blood |
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The landmark discrimination learning test can be used to assess the ability to utilize allocentric spatial information to locate targets. The present experiments examined the role of various factors on performance of a landmark discrimination learning task in beagle dogs. Experiments 1 and 2 looked at the effects of age and food composition. Experiments 3 and 4 were aimed at characterizing the cognitive strategies used in performance on this task and in long-term retention. Cognitively equivalent groups of old and young dogs were placed into either a test group maintained on food enriched with a broad-spectrum of antioxidants and mitochondrial cofactors, or a control group maintained on a complete and balanced food formulated for adult dogs. Following a wash-in period, the dogs were tested on a series of problems, in which reward was obtained when the animal responded selectively to the object closest to a thin wooden block, which served as a landmark. In Experiment 1, dogs were first trained to respond to a landmark placed directly on top of coaster, landmark 0 (L0). In the next phase of testing, the landmark was moved at successively greater distances (1, 4 or 10 cm) away from the reward object. Learning varied as a function of age group, food group, and task. The young dogs learned all of the tasks more quickly than the old dogs. The aged dogs on the enriched food learned L0 significantly more rapidly than aged dogs on control food. A higher proportion of dogs on the enriched food learned the task, when the distance was increased to 1cm. Experiment 2 showed that accuracy decreased with increased distance between the reward object and landmark, and this effect was greater in old animals. Experiment 3 showed stability of performance, despite using a novel landmark, and new locations, indicating that dogs learned the landmark concept. Experiment 4 found age impaired long-term retention of the landmark task. These results indicate that allocentric spatial learning is impaired in an age-dependent manner in dogs, and that age also affects performance when the distance between the landmark and target is increased. In addition, these results both support a role of oxidative damage in the development of age-associated cognitive dysfunction and indicate that short-term administration of a food enriched with supplemental antioxidants and mitochondrial cofactors can partially reverse the deleterious effects of aging on cognition. |
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Life Science Division, University of Toronto at Scarborough, 1265 Military Trail, Scarborough, Ont., Canada M1C 1A4. milgram@psych.utoronto.ca |
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0149-7634 |
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PMID:12479842 |
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Call Number |
Equine Behaviour @ team @ |
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2806 |
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Author |
Domjan, M. |
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Title |
Determinants of the enhancement of flavored-water intake by prior exposure |
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Journal Article |
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Year |
1976 |
Publication |
Journal of Experimental Psychology. Animal Behavior Processes |
Abbreviated Journal |
J Exp Psychol Anim Behav Process |
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Volume |
2 |
Issue |
1 |
Pages |
17-27 |
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Keywords |
Animals; Arousal; *Awareness; Behavior, Animal; *Cognition; *Drinking Behavior; Environment; Escape Reaction; Fear; Male; Rats; Saccharin/administration & dosage; *Taste; Thirst; Time Factors; Water Deprivation |
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Abstract |
The intake of a 2.0% sodium saccharin solution in rats was observed to increase as a function of both the number (Experiment 1) and the duration (Experiment 3) of prior periods of access to the saccharin flavor, but did not increase when subjects were maintained on a fluid deprivation procedure in the absence of saccharin exposure (Experiment 2). The enhancement of intake was further influenced by the schedule of saccharin preexposures in the absence of variations in the amount of solution tasted (Experiment 4). The effect was not a function of the opportunity for subjects to determine their own pattern of contact with the saccharin flavor, the opportunity for association of the flavor with hunger and thirst reduction, or the amount of saccharin swallowed during preexposure (Experiment 5). These results suggest that mere exposure to a flavored solution is sufficient to increase subsequent intakes. The phenomenon is discussed in terms of the attenuation of neophobia elicited by the novelty of flavored solutions. |
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0097-7403 |
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PMID:1249524 |
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Equine Behaviour @ team @ |
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2790 |
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Touma, C.; Sachser, N.; Mostl, E.; Palme, R. |
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Title |
Effects of sex and time of day on metabolism and excretion of corticosterone in urine and feces of mice |
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Journal Article |
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Year |
2003 |
Publication |
General and Comparative Endocrinology |
Abbreviated Journal |
Gen Comp Endocrinol |
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130 |
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3 |
Pages |
267-278 |
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Keywords |
Animals; Chromatography, High Pressure Liquid; Circadian Rhythm/*physiology; Corticosterone/*metabolism/urine; Feces/*chemistry; Female; Immunoenzyme Techniques; Kinetics; Male; Mice; Mice, Inbred C57BL; Reference Values; Sex Factors; Stress/metabolism; Time Factors; Tritium |
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Abstract |
Non-invasive techniques to monitor stress hormones in small animals like mice offer several advantages and are highly demanded in laboratory as well as in field research. Since knowledge about the species-specific metabolism and excretion of glucocorticoids is essential to develop such a technique, we conducted radiometabolism studies in mice (Mus musculus f. domesticus, strain C57BL/6J). Each mouse was injected intraperitoneally with 740 kBq of 3H-labelled corticosterone and all voided urine and fecal samples were collected for five days. In a first experiment 16 animals (eight of each sex) received the injection at 9 a.m., while eight mice (four of each sex) were injected at 9 p.m. in a second experiment. In both experiments radioactive metabolites were recovered predominantly in the feces, although males excreted significantly higher proportions via the feces (about 73%) than females (about 53%). Peak radioactivity in the urine was detected within about 2h after injection, while in the feces peak concentrations were observed later (depending on the time of injection: about 10h postinjection in experiment 1 and about 4h postinjection in experiment 2, thus proving an effect of the time of day). The number and relative abundance of fecal [3H]corticosterone metabolites was determined by high performance liquid chromatography (HPLC). The HPLC separations revealed that corticosterone was extensively metabolized mainly to more polar substances. Regarding the types of metabolites formed, significant differences were found between males and females, but not between the experiments. Additionally, the immunoreactivity of these metabolites was assessed by screening the HPLC fractions with four enzyme immunoassays (EIA). However, only a newly established EIA for 5alpha-pregnane-3beta,11beta,21-triol-20-one (measuring corticosterone metabolites with a 5alpha-3beta,11beta-diol structure) detected several peaks of radioactive metabolites with high intensity in both sexes, while the other EIAs showed only minor immunoreactivity. Thus, our study for the first time provides substantial information about metabolism and excretion of corticosterone in urine and feces of mice and is the first demonstrating a significant impact of the animals' sex and the time of day. Based on these data it should be possible to monitor adrenocortical activity non-invasively in this species by measuring fecal corticosterone metabolites with the newly developed EIA. Since mice are extensively used in research world-wide, this could open new perspectives in various fields from ecology to behavioral endocrinology. |
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Department of Behavioral Biology, Institute of Neuro and Behavioral Biology, University of Muenster, Badestrasse 9, D-48149 Muenster, Germany. touma@uni-muenster.de |
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0016-6480 |
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PMID:12606269 |
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no |
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Equine Behaviour @ team @ |
Serial |
4086 |
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Williams, J.L.; Friend, T.H.; Collins, M.N.; Toscano, M.J.; Sisto-Burt, A.; Nevill, C.H. |
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Title |
Effects of imprint training procedure at birth on the reactions of foals at age six months |
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Journal Article |
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Year |
2003 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
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Volume |
35 |
Issue |
2 |
Pages |
127-132 |
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Keywords |
Age Factors; Animal Husbandry/methods; Animals; Animals, Newborn/*psychology; *Behavior, Animal; *Bonding, Human-Pet; Female; Handling (Psychology); Horses/*psychology; Humans; *Imprinting (Psychology); Male; Random Allocation; Socialization; Time Factors |
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REASONS FOR PERFORMING STUDY: While imprint training procedures have been promoted in popular magazines, they have received limited scientific investigation. OBJECTIVES: To determine the effects of a neonatal imprint training procedure on 6-month-old foals and to determine if any one session had a greater effect than others. METHODS: Foals (n = 131) were divided into the following treatments: no imprint training, imprint training at birth, 12, 24 and 48 h after birth or imprint training only at birth, 12, 24, 48, or 72 h after birth. Foals then received minimal human handling until they were tested at 6 months. RESULTS: During training, time to complete exposure to the stimulus was significant for only 2 of 6 stimuli. Percentage change in baseline heart rate was significant for only 2 of 10 stimuli. These 4 effects were randomly spread across treatments. CONCLUSIONS: Neither the number of imprint training sessions (0, 1, or 4) nor the timing of imprint training sessions (none, birth, 12, 24, 48, or 72 h after birth) influenced the foal's behaviour at 6 months of age. POTENTIAL CLINICAL RELEVANCE: In this study, imprint training did not result in better behaved, less reactive foals. |
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Department of Animal Science, 2471 TAMUS, Texas A&M University College Station, Texas 77845-2471, USA |
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0425-1644 |
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PMID:12638787 |
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1908 |
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Author |
Fairhurst, S.; Gallistel, C.R.; Gibbon, J. |
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Title |
Temporal landmarks: proximity prevails |
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Journal Article |
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Year |
2003 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
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Volume |
6 |
Issue |
2 |
Pages |
113-120 |
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Keywords |
Animals; Columbidae; Conditioning, Operant; Reaction Time; *Time Perception |
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Abstract |
Subjects in conditioning experiments time their conditioned responses relative to the onsets of the conditioned stimuli (CSs). These onsets are temporal landmarks, by reference to which subjects may estimate the location of the unconditioned stimulus (US) in time. In a serial compound conditioning paradigm, a long duration CS comes on first, followed later by a second shorter CS, creating both a long-range and a short-range predictor of the US. We ask whether displacing the short-range predictor relative to the long-range predictor causes subjects to strike a compromise between the different temporal locations predicted by the two CSs. In three experiments with pigeons, we varied the training conditions so as to favor or militate against this outcome. However, in all conditions, there was no compromise; after the onset of the displaced short-range CS, the timing of conditioned responding was governed by it alone. This result contrasts with the compromises that are seen when the feeding time predicted by a CS is put in conflict with the time predicted by the circadian clock, and with the similar compromises sometimes seen when a nearby spatial landmark is displaced relative to a larger spatial context. |
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New York State Psychiatric Institute, 1051 Riverside Dr., Unit 50, New York, NY 10032, USA |
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1435-9448 |
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PMID:12720110 |
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Equine Behaviour @ team @ |
Serial |
2573 |
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Author |
Stoet, G.; Snyder, L.H. |
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Title |
Task preparation in macaque monkeys ( Macaca mulatta) |
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Journal Article |
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Year |
2003 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
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Volume |
6 |
Issue |
2 |
Pages |
121-130 |
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Animals; *Cognition; Conditioning, Classical; Macaca mulatta/*psychology; Male; Reaction Time; Task Performance and Analysis; Visual Perception |
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Abstract |
We investigated whether macaque monkeys possess the ability to prepare abstract tasks in advance. We trained two monkeys to use different stimulus-response (S-R) mappings. On each trial, monkeys were first informed with a visual cue which of two S-R mapping to use. Following a delay, a visual target was presented to which they would respond with a left or right button-press. We manipulated delay time between cue and target and found that performance was faster and more accurate with longer delays, suggesting that monkeys used the delay time to prepare each task in advance. |
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Department of Anatomy and Neurobiology, Washington University School of Medicine, 660 S Euclid Ave., Box 8108, St. Louis, MO 63110, USA. stoet@pcg.wustl.edu |
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1435-9448 |
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PMID:12721788 |
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Equine Behaviour @ team @ |
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2572 |
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Author |
Rands, S.A.; Cowlishaw, G.; Pettifor, R.A.; Rowcliffe, J.M.; Johnstone, R.A. |
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Title |
Spontaneous emergence of leaders and followers in foraging pairs |
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Journal Article |
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Year |
2003 |
Publication |
Nature |
Abbreviated Journal |
Nature |
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Volume |
423 |
Issue |
6938 |
Pages |
432-434 |
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Animals; *Energy Metabolism; Food; *Food Chain; *Models, Biological; Motor Activity; *Social Behavior; Time Factors |
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Abstract |
Animals that forage socially often stand to gain from coordination of their behaviour. Yet it is not known how group members reach a consensus on the timing of foraging bouts. Here we demonstrate a simple process by which this may occur. We develop a state-dependent, dynamic game model of foraging by a pair of animals, in which each individual chooses between resting or foraging during a series of consecutive periods, so as to maximize its own individual chances of survival. We find that, if there is an advantage to foraging together, the equilibrium behaviour of both individuals becomes highly synchronized. As a result of this synchronization, differences in the energetic reserves of the two players spontaneously develop, leading them to adopt different behavioural roles. The individual with lower reserves emerges as the 'pace-maker' who determines when the pair should forage, providing a straightforward resolution to the problem of group coordination. Moreover, the strategy that gives rise to this behaviour can be implemented by a simple 'rule of thumb' that requires no detailed knowledge of the state of other individuals. |
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Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK. s.rands@zoo.cam.ac.uk |
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0028-0836 |
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PMID:12761547 |
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no |
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Equine Behaviour @ team @ |
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5138 |
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Gavrilova, O.; Haluzik, M.; Matsusue, K.; Cutson, J.J.; Johnson, L.; Dietz, K.R.; Nicol, C.J.; Vinson, C.; Gonzalez, F.J.; Reitman, M.L. |
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Title |
Liver peroxisome proliferator-activated receptor gamma contributes to hepatic steatosis, triglyceride clearance, and regulation of body fat mass |
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Journal Article |
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Year |
2003 |
Publication |
The Journal of biological chemistry |
Abbreviated Journal |
J Biol Chem |
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Volume |
278 |
Issue |
36 |
Pages |
34268-34276 |
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Keywords |
Adipose Tissue/*metabolism; Animals; Blotting, Southern; Blotting, Western; Female; Hypoglycemia/genetics; Insulin Resistance/genetics; Lipid Metabolism; Liver/*metabolism; Liver Diseases/genetics/*metabolism; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Mice, Transgenic; RNA/metabolism; Receptors, Cytoplasmic and Nuclear/*genetics/*physiology; Recombination, Genetic; Thiazoles/pharmacology; *Thiazolidinediones; Time Factors; Transcription Factors/*genetics/*physiology; Triglycerides/*metabolism |
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Abstract |
Peroxisome proliferator-activated receptor gamma (PPAR gamma) is a nuclear receptor that mediates the antidiabetic effects of thiazolidinediones. PPAR gamma is present in adipose tissue and becomes elevated in fatty livers, but the roles of specific tissues in thiazolidinedione actions are unclear. We studied the function of liver PPAR gamma in both lipoatrophic A-ZIP/F-1 (AZIP) and wild type mice. In AZIP mice, ablation of liver PPAR gamma reduced the hepatic steatosis but worsened the hyperlipidemia, triglyceride clearance, and muscle insulin resistance. Inactivation of AZIP liver PPAR gamma also abolished the hypoglycemic and hypolipidemic effects of rosiglitazone, demonstrating that, in the absence of adipose tissue, the liver is a primary and major site of thiazolidinedione action. In contrast, rosiglitazone remained effective in non-lipoatrophic mice lacking liver PPAR gamma, suggesting that adipose tissue is the major site of thiazolidinedione action in typical mice with adipose tissue. Interestingly, mice without liver PPAR gamma, but with adipose tissue, developed relative fat intolerance, increased adiposity, hyperlipidemia, and insulin resistance. Thus, liver PPAR gamma regulates triglyceride homeostasis, contributing to hepatic steatosis, but protecting other tissues from triglyceride accumulation and insulin resistance. |
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Diabetes Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA. oksanag@bdg10.niddk.nih.gov |
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English |
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0021-9258 |
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PMID:12805374 |
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refbase @ user @ |
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81 |
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