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Author |
Santos, L.R.; Miller, C.T.; Hauser, M.D. |
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Title |
Representing tools: how two non-human primate species distinguish between the functionally relevant and irrelevant features of a tool |
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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 |
4 |
Pages |
269-281 |
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Keywords |
Animals; *Discrimination Learning; Female; Form Perception/*physiology; Habituation, Psychophysiologic/*physiology; Imitative Behavior; Macaca mulatta/*growth & development/*psychology; Male; Motor Skills; Practice (Psychology); Saguinus/*growth & development/*psychology; Species Specificity |
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Abstract |
Few studies have examined whether non-human tool-users understand the properties that are relevant for a tool's function. We tested cotton-top tamarins (Saguinus oedipus) and rhesus macaques (Macaca mulatta) on an expectancy violation procedure designed to assess whether these species make distinctions between the functionally relevant and irrelevant features of a tool. Subjects watched an experimenter use a tool to push a grape down a ramp, and then were presented with different displays in which the features of the original tool (shape, color, orientation) were selectively varied. Results indicated that both species looked longer when a newly shaped stick acted on the grape than when a newly colored stick performed the same action, suggesting that both species perceive shape as a more salient transformation than color. In contrast, tamarins, but not rhesus, attended to changes in the tool's orientation. We propose that some non-human primates begin with a predisposition to attend to a tool's shape and, with sufficient experience, develop a more sophisticated understanding of the features that are functionally relevant to tools. |
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Department of Psychology, Harvard University, Cambridge, MA 02138, USA. laurie.santos@yale.edu |
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1435-9448 |
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PMID:12736800 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2570 |
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Author |
Freire, R.; Wilkins, L.J.; Short, F.; Nicol, C.J. |
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Title |
Behaviour and welfare of individual laying hens in a non-cage system |
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Journal Article |
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Year |
2003 |
Publication |
British poultry science |
Abbreviated Journal |
Br Poult Sci |
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Volume |
44 |
Issue |
1 |
Pages |
22-29 |
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Keywords |
*Animal Welfare; Animals; *Behavior, Animal; *Chickens; Female; Housing, Animal/*standards; Oviposition |
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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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Department of Clinical Veterinary Science, University of Bristol, Langford, Bristol, England. rkfreire@hotmail.com |
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0007-1668 |
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PMID:12737221 |
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refbase @ user @ |
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82 |
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Author |
Washburn, D.A.; Astur, R.S. |
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Title |
Exploration of virtual mazes by rhesus 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 |
3 |
Pages |
161-168 |
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Keywords |
Animals; Choice Behavior/*physiology; Computer Peripherals; Macaca mulatta/*physiology; Male; Maze Learning/*physiology; Space Perception/*physiology; User-Computer Interface |
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Abstract |
A chasm divides the huge corpus of maze studies found in the literature, with animals tested in mazes on the one side and humans tested with mazes on the other. Advances in technology and software have made possible the production and use of virtual mazes, which allow humans to navigate computerized environments and thus for humans and nonhuman animals to be tested in comparable spatial domains. In the present experiment, this comparability is extended even further by examining whether rhesus monkeys (Macaca mulatta) can learn to explore virtual mazes. Four male macaques were trained to manipulate a joystick so as to move through a virtual environment and to locate a computer-generated target. The animals succeeded in learning this task, and located the target even when it was located in novel alleys. The search pattern within the maze for these animals resembled the pattern of maze navigation observed for monkeys that were tested on more traditional two-dimensional computerized mazes. |
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Department of Psychology, Georgia State University, Atlanta, GA 30303, USA. dwashburn@gsu.edu |
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1435-9448 |
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PMID:12750961 |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2569 |
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Author |
Dyson, S.; Murray, R. |
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Title |
Pain associated with the sacroiliac joint region: a clinical study of 74 horses |
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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 |
3 |
Pages |
240-245 |
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Keywords |
Age Factors; Analgesia/veterinary; Anesthetics, Local/pharmacology; Animals; Body Height; Body Weight; Breeding; Female; Forelimb; Gait; Hindlimb; Horse Diseases/*diagnosis/radionuclide imaging; Horses; Lameness, Animal/*physiopathology; Lumbar Vertebrae/physiopathology; Male; Pain/diagnosis/drug therapy/radionuclide imaging/*veterinary; Sacroiliac Joint/*physiopathology; Sacrum/physiopathology |
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Abstract |
REASONS FOR PERFORMING STUDY: There has been no large study of horses with suspected sacroiliac (SI) joint region pain in which the clinical diagnosis has been supported by either abnormal radiopharmaceutical activity in the SI joint region or by periarticular infiltration of local anaesthetic solution. OBJECTIVES: To describe the clinical features of horses with SI joint region pain, to document the age, breed, sex, discipline, size and conformation of affected horses and to compare these with the author's (SD) normal case population and to document the results of infiltration of local anaesthetic solution around the SI joint region. METHODS: Horses were selected for inclusion in the study based upon the exclusion of other causes of lameness or poor performance, together with clinical signs suggestive of SI joint pain and abnormal radiopharmaceutical activity in the SI joint region and/or a positive response to periarticular infiltration of local anaesthetic solution. RESULTS: Sacroiliac joint region disease was identified in 74 horses between November 1997 and March 2002. Dressage and showjumping horses appeared to be at particular risk (P < 0.001). Affected horses were generally slightly older than the normal clinic population (P < 0.0001), taller at the withers (P < 0.0001) and of greater bodyweight (P < 0.01). There was a significant effect of breed (P < 0.001), with a substantially higher proportion of Warmblood horses (51%) in the SI pain group compared to the normal clinic population (29%). There was no correlation between conformation and the presence of SI joint region pain. The tubera sacrale appeared grossly symmetrical in most (95%) horses. Poor development of the epaxial muscles in the thoracolumbar region and asymmetry of the hindquarter musculature were common. Twenty-six horses (35%) showed restricted flexibility of the thoracolumbar region and 10 (16%) had an exaggerated response to pressure applied over the tubera sacrale. Fourteen horses (19%) were reluctant to stand on one hindlimb for prolonged periods. The majority of horses (75%) had a straight hindlimb flight and only 18% moved closely behind or plaited. In all horses restricted hindlimb impulsion was the predominant feature; invariably this was most obvious when the horse was ridden. Stiffness, unwillingness to work on the bit and poor quality canter were common. Sacroiliac joint region pain was seen alone (47%), or in conjunction with thoracolumbar pain (16%), hindlimb lameness (20%), forelimb lameness (7%) or a combination of problems (10%). Seventy-three horses (99%) had abnormalities of the SI joint region identified using nuclear scintigraphy. Infiltration of local anaesthetic solution around the SI joint region produced profound improvement in gait in all 34 horses in which it was performed. CONCLUSIONS AND POTENTIAL RELEVANCE: Careful clinical examination combined with scintigraphic evaluation of the SI joint region and local analgesia can enable a more definitive diagnosis of SI joint region pain than has previously been possible. |
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Centre for Equine Studies, Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk CB8 7UU, UK |
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0425-1644 |
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PMID:12755425 |
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Call Number |
Equine Behaviour @ team @ |
Serial |
3723 |
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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 |
Type |
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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Keywords |
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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Address |
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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Call Number |
Equine Behaviour @ team @ |
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5138 |
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Author |
McGonigle, B.; Chalmers, M.; Dickinson, A. |
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Title |
Concurrent disjoint and reciprocal classification by Cebus apella in seriation tasks: evidence for hierarchical organization |
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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 |
3 |
Pages |
185-197 |
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Keywords |
Animals; Cebus/*physiology; Discrimination Learning/*physiology; Female; Form Perception/*physiology; Male; *Task Performance and Analysis; Visual Perception/*physiology |
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Abstract |
We report the results of a 4-year-long study of capuchin monkeys ( Cebus apella ) on concurrent three-way classification and linear size seriation tasks using explicit ordering procedures, requiring subjects to select icons displayed on touch screens rather than manipulate and sort actual objects into groups. The results indicate that C. apella is competent to classify nine items concurrently, first into three disjoint classes where class exemplars are identical to one another, then into three reciprocal classes which share common exemplar (size) features. In the final phase we compare the relative efficiency of executive control under conditions where both hierarchical and/or linear organization can be utilized. Whilst this shows a superiority of categorical based size seriation for a nine item test set suggesting an adaptive advantage for hierarchical over linear organization, Cebus nevertheless achieved high levels of principled linear size seriation with sequence lengths not normally achieved by children below the age of six years. |
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Laboratory for Cognitive Neuroscience, Centre for Neuroscience, University of Edinburgh, Appleton Tower, George Square, Edinburgh EH 8 9QJ, UK. ejua48@holyrood.ed.ac.uk |
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1435-9448 |
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PMID:12761655 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2568 |
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Author |
Iversen, I.H.; Matsuzawa, T. |
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Title |
Development of interception of moving targets by chimpanzees (Pan troglodytes) in an automated task |
Type |
Journal Article |
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Year |
2003 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
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Volume |
6 |
Issue |
3 |
Pages |
169-183 |
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Keywords |
Animals; Female; Hand/physiology; Motion Perception/*physiology; Movement/physiology; Pan troglodytes/*physiology; Spatial Behavior/*physiology; *Task Performance and Analysis; User-Computer Interface; Visual Perception/physiology |
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Abstract |
The experiments investigated how two adult captive chimpanzees learned to navigate in an automated interception task. They had to capture a visual target that moved predictably on a touch monitor. The aim of the study was to determine the learning stages that led to an efficient strategy of intercepting the target. The chimpanzees had prior training in moving a finger on a touch monitor and were exposed to the interception task without any explicit training. With a finger the subject could move a small “ball” at any speed on the screen toward a visual target that moved at a fixed speed either back and forth in a linear path or around the edge of the screen in a rectangular pattern. Initial ball and target locations varied from trial to trial. The subjects received a small fruit reinforcement when they hit the target with the ball. The speed of target movement was increased across training stages up to 38 cm/s. Learning progressed from merely chasing the target to intercepting the target by moving the ball to a point on the screen that coincided with arrival of the target at that point. Performance improvement consisted of reduction in redundancy of the movement path and reduction in the time to target interception. Analysis of the finger's movement path showed that the subjects anticipated the target's movement even before it began to move. Thus, the subjects learned to use the target's initial resting location at trial onset as a predictive signal for where the target would later be when it began moving. During probe trials, where the target unpredictably remained stationary throughout the trial, the subjects first moved the ball in anticipation of expected target movement and then corrected the movement to steer the ball to the resting target. Anticipatory ball movement in probe trials with novel ball and target locations (tested for one subject) showed generalized interception beyond the trained ball and target locations. The experiments illustrate in a laboratory setting the development of a highly complex and adaptive motor performance that resembles navigational skills seen in natural settings where predators intercept the path of moving prey. |
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Department of Psychology, University of North Florida, Jacksonville, FL 32224, USA. iiversen@unf.edu |
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1435-9448 |
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PMID:12761656 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2567 |
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Author |
Pinchbeck, G.L.; Clegg, P.D.; Proudman, C.J.; Morgan, K.L.; French, N.P. |
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Title |
Case-control study to investigate risk factors for horse falls in hurdle racing in England and Wales |
Type |
Journal Article |
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Year |
2003 |
Publication |
The Veterinary Record |
Abbreviated Journal |
Vet. Rec. |
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Volume |
152 |
Issue |
19 |
Pages |
583-587 |
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Keywords |
Accidental Falls/*statistics & numerical data; Animals; Athletic Injuries/epidemiology/etiology/*veterinary; Case-Control Studies; England/epidemiology; Horses/*injuries; Risk Factors; Running/injuries; Wales/epidemiology |
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Abstract |
Between March 1, 2000 and August 31, 2001, a case-control study was conducted on 12 racecourses in England and Wales to identify and quantify the risk factors associated with horse falls in hurdle races. The cases and controls were defined so that variables relating to the horse, the jockey, the race and racecourse, and the jump could be considered. The cases were defined as a jumping effort at a hurdle flight that resulted in a fall, and the controls were defined as a successful jump over a hurdle at any of the 12 racecourses within 14 days before or after the case fall. Conditional logistic regression was used to examine the univariable and multivariable relationships between the predictor variables and the risk of falling. The risk of falling was significantly associated with the position of the jump in the race, and with the distance and speed of the race. A horse's previous racing experience and history were also significantly associated with the risk of falling and horses participating in their first hurdle race were at almost five times greater risk of falling than horses that had hurdled before. |
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Epidemiology Group, Department of Veterinary Clinical Science and Animal Husbandry, University of Liverpool, Leahurst, Neston CH64 7TE |
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English |
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ISSN |
0042-4900 |
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PMID:12762486 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
3782 |
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Author |
Brilot, B.O.; Johnstone, R.A. |
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Title |
The limits to cost-free signalling of need between relatives |
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Journal Article |
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Year |
2003 |
Publication |
Proceedings. Biological sciences / The Royal Society |
Abbreviated Journal |
Proc Biol Sci |
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Volume |
270 |
Issue |
1519 |
Pages |
1055-1060 |
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*Animal Communication; Animals; Birds/physiology; Models, Biological; *Social Behavior |
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Abstract |
Theoretical models have demonstrated the possibility of stable cost-free signalling of need between relatives. The stability of these cost-free equilibria depends on the indirect fitness cost of cheating and deceiving a donor into giving away resources. We show that this stability is highly sensitive to the distribution of need among signallers and receivers. In particular, cost-free signalling is likely to prove stable only if there is very large variation in need (such that the least-needy individuals stand to gain much less than the most-needy individuals from additional resources). We discuss whether these conditions are likely to be found in altricial avian breeding systems--the most intensively studied instance of signalling of need between relatives. We suggest that cost-free signalling is more likely to prove stable and will provide parents with more information during the earlier phases of chick growth, when parents can more easily meet the demands of a brood (and chicks are more likely to reach satiation). Later, informative yet cost-free signalling is unlikely to persist. |
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Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK. bob21@cam.ac.uk |
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English |
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0962-8452 |
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PMID:12803895 |
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no |
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Call Number |
refbase @ user @ |
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558 |
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Author |
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 |
Type |
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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