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| Author | Hamilton, W.D. | ||||
| Title | Geometry for the selfish herd | Type  |
Journal Article | ||
| Year | 1971 | Publication | Journal of theoretical biology | Abbreviated Journal | J. Theor. Biol. |
| Volume | 31 | Issue | 2 | Pages | 295-311 |
| Keywords | Animals; Anura; *Behavior, Animal; Breeding; Communication; Evolution; Fear; Metallurgy; *Models, Biological; Probability; Snakes; *Spatial Behavior | ||||
| Abstract | This paper presents an antithesis to the view that gregarious behaviour is evolved through benefits to the population or species. Following Galton (1871) and Williams (1964) gregarious behaviour is considered as a form of cover-seeking in which each animal tries to reduce its chance of being caught by a predator. It is easy to see how pruning of marginal individuals can maintain centripetal instincts in already gregarious species; some evidence that marginal pruning actually occurs is summarized. Besides this, simply defined models are used to show that even in non-gregarious species selection is likely to favour individuals who stay close to others. Although not universal or unipotent, cover-seeking is a widespread and important element in animal aggregation, as the literature shows. Neglect of the idea has probably followed from a general disbelief that evolution can be dysgenic for a species. Nevertheless, selection theory provides no support for such disbelief in the case of species with outbreeding or unsubdivided populations. The model for two dimensions involves a complex problem in geometrical probability which has relevance also in metallurgy and communication science. Some empirical data on this, gathered from random number plots, is presented as of possible heuristic value. |
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| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0022-5193 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:5104951 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 771 | ||
| Permanent link to this record | |||||
| Author | Jansen, T.; Forster, P.; Levine, M.A.; Oelke, H.; Hurles, M.; Renfrew, C.; Weber, J.; Olek, K. | ||||
| Title | Mitochondrial DNA and the origins of the domestic horse | Type |
Journal Article | ||
| Year | 2002 | Publication | Proceedings of the National Academy of Sciences of the United States of America | Abbreviated Journal | Proc. Natl. Acad. Sci. U.S.A. |
| Volume | 99 | Issue | 16 | Pages | 10905-10910 |
| Keywords | Animals; Animals, Domestic/classification/*genetics; Base Sequence; DNA, Complementary; *DNA, Mitochondrial; *Evolution, Molecular; Horses/classification/*genetics; Molecular Sequence Data; Phylogeny | ||||
| Abstract | The place and date of the domestication of the horse has long been a matter for debate among archaeologists. To determine whether horses were domesticated from one or several ancestral horse populations, we sequenced the mitochondrial D-loop for 318 horses from 25 oriental and European breeds, including American mustangs. Adding these sequences to previously published data, the total comes to 652, the largest currently available database. From these sequences, a phylogenetic network was constructed that showed that most of the 93 different mitochondrial (mt)DNA types grouped into 17 distinct phylogenetic clusters. Several of the clusters correspond to breeds and/or geographic areas, notably cluster A2, which is specific to Przewalski's horses, cluster C1, which is distinctive for northern European ponies, and cluster D1, which is well represented in Iberian and northwest African breeds. A consideration of the horse mtDNA mutation rate together with the archaeological timeframe for domestication requires at least 77 successfully breeding mares recruited from the wild. The extensive genetic diversity of these 77 ancestral mares leads us to conclude that several distinct horse populations were involved in the domestication of the horse. | ||||
| Address | Biopsytec Analytik GmbH, Marie-Curie-Strasse 1, 53359 Rheinbach, Germany. jansen@biopsytec.com | ||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0027-8424 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:12130666 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 772 | ||
| Permanent link to this record | |||||
| Author | Hirsch, B.T. | ||||
| Title | Costs and benefits of within-group spatial position: a feeding competition model | Type |
Journal Article | ||
| Year | 2007 | Publication | The Quarterly review of biology | Abbreviated Journal | Q Rev Biol |
| Volume | 82 | Issue | 1 | Pages | 9-27 |
| Keywords | Animals; Competitive Behavior/*physiology; Dominance-Subordination; Feeding Behavior/*physiology/*psychology; Population Dynamics; Predatory Behavior/*physiology | ||||
| Abstract | An animal's within-group spatial position has several important fitness consequences. Risk of predation, time spent engaging in antipredatory behavior and feeding competition can all vary with respect to spatial position. Previous research has found evidence that feeding rates are higher at the group edge in many species, but these studies have not represented the entire breadth of dietary diversity and ecological situations faced by many animals. In particular the presence of concentrated, defendable food patches can lead to increased feeding rates by dominants in the center of the group that are able to monopolize or defend these areas. To fully understand the tradeoffs of within-group spatial position in relation to a variety of factors, it is important to be able to predict where individuals should preferably position themselves in relation to feeding rates and food competition. A qualitative model is presented here to predict how food depletion time, abundance of food patches within a group, and the presence of prior knowledge of feeding sites affect the payoffs of different within-group spatial positions for dominant and subordinate animals. In general, when feeding on small abundant food items, individuals at the front edge of the group should have higher foraging success. When feeding on slowly depleted, rare food items, dominants will often have the highest feeding rates in the center of the group. Between these two extreme points of a continuum, an individual's optimal spatial position is predicted to be influenced by an additional combination of factors, such as group size, group spread, satiation rates, and the presence of producer-scrounger tactics. | ||||
| Address | Department of Anthropology, Stony Brook University Stony Brook, New York 11794, USA. BTHIRSCH@IC.SUNYSB.EDU | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0033-5770 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:17354992 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 803 | ||
| Permanent link to this record | |||||
| Author | Li, F.-H.; Zhong, W.-Q.; Wang, Z.; Wang, D.-H. | ||||
| Title | Rank in a food competition test and humoral immune functions in male Brandt's voles (Lasiopodomys brandtii) | Type |
Journal Article | ||
| Year | 2007 | Publication | Physiology & behavior | Abbreviated Journal | Physiol. Behav. |
| Volume | 90 | Issue | 2-3 | Pages | 490-495 |
| Keywords | Animals; Antibody Formation/*physiology; Arvicolinae/immunology/*physiology; Competitive Behavior/*physiology; *Dominance-Subordination; Feeding Behavior/physiology; Hydrocortisone/blood; Male; *Social Dominance; Spleen/immunology/physiology | ||||
| Abstract | Social status can influence an animal's immune and reproductive functions, eventually leading to alterations in immunocompetence and reproductive success. Here, we report that rank assessed in a food competition test, considered as an index of social status, has significant influences on humoral immune functions in male Brandt's voles (Lasiopodomys brandtii) living in a group. Our data reveal a negative correlation of the spleen mass and serum antibody levels with social status, as well as a positive correlation of serum cortisol levels with social status. Males winning in food competition had a smaller spleen, a lower level of serum antibodies, and a higher level of serum cortisol than did their conspecific counterparts. These data indicate interactions between social status and humoral immune functions and might illustrate a trade-off between infection risks and reproductive success in male Brandt's voles. | ||||
| Address | State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, The Chinese Academy of Sciences, No. 25 Beisihuan Xilu, Zhongguancun, Haidian, Beijing 100080, China | ||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0031-9384 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:17141282 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 804 | ||
| Permanent link to this record | |||||
| Author | Biro, D.; Sumpter, D.J.T.; Meade, J.; Guilford, T. | ||||
| Title | From Compromise to Leadership in Pigeon Homing | Type |
Journal Article | ||
| Year | 2006 | Publication | Current Biology | Abbreviated Journal | Curr Biol |
| Volume | 16 | Issue | 21 | Pages | 2123-2128 |
| Keywords | Animal Migration; Animals; Columbidae/*physiology; Decision Making; *Flight, Animal; *Homing Behavior; Models, Biological; Orientation; *Social Behavior; *Social Dominance | ||||
| Abstract | Summary A central problem faced by animals traveling in groups is how navigational decisions by group members are integrated, especially when members cannot assess which individuals are best informed or have conflicting information or interests , , , and . Pigeons are now known to recapitulate faithfully their individually distinct habitual routes home , and , and this provides a novel paradigm for investigating collective decisions during flight under varying levels of interindividual conflict. Using high-precision GPS tracking of pairs of pigeons, we found that if conflict between two birds' directional preferences was small, individuals averaged their routes, whereas if conflict rose over a critical threshold, either the pair split or one of the birds became the leader. Modeling such paired decision-making showed that both outcomes--compromise and leadership--could emerge from the same set of simple behavioral rules. Pairs also navigated more efficiently than did the individuals of which they were composed, even though leadership was not necessarily assumed by the more efficient bird. In the context of mass migration of birds and other animals, our results imply that simple self-organizing rules can produce behaviors that improve accuracy in decision-making and thus benefit individuals traveling in groups , and . | ||||
| Address | Department of Zoology, University of Oxford, Oxford OX1 3PS, United Kingdom. daro.biro@zoo.ox.ac.uk | ||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Englisch | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0960-9822 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:17084696 | Approved | no | ||
| Call Number | Serial | 2026 | |||
| Permanent link to this record | |||||
| Author | Fragaszy, D.; Visalberghi, E. | ||||
| Title | Socially biased learning in monkeys | Type |
Journal Article | ||
| Year | 2004 | Publication | Learning & behavior : a Psychonomic Society publication | Abbreviated Journal | Learn Behav |
| Volume | 32 | Issue | 1 | Pages | 24-35 |
| Keywords | Adaptation, Psychological; Animal Communication; Animals; Behavior, Animal; *Feeding Behavior/psychology; Food Preferences/psychology; Haplorhini/*psychology; *Imitative Behavior; Imprinting (Psychology); *Learning; *Social Environment; *Social Facilitation | ||||
| Abstract | We review socially biased learning about food and problem solving in monkeys, relying especially on studies with tufted capuchin monkeys (Cebus apella) and callitrichid monkeys. Capuchin monkeys most effectively learn to solve a new problem when they can act jointly with an experienced partner in a socially tolerant setting and when the problem can be solved by direct action on an object or substrate, but they do not learn by imitation. Capuchin monkeys are motivated to eat foods, whether familiar or novel, when they are with others that are eating, regardless of what the others are eating. Thus, social bias in learning about foods is indirect and mediated by facilitation of feeding. In most respects, social biases in learning are similar in capuchins and callitrichids, except that callitrichids provide more specific behavioral cues to others about the availability and palatability of foods. Callitrichids generally are more tolerant toward group members and coordinate their activity in space and time more closely than capuchins do. These characteristics support stronger social biases in learning in callitrichids than in capuchins in some situations. On the other hand, callitrichids' more limited range of manipulative behaviors, greater neophobia, and greater sensitivity to the risk of predation restricts what these monkeys learn in comparison with capuchins. We suggest that socially biased learning is always the collective outcome of interacting physical, social, and individual factors, and that differences across populations and species in social bias in learning reflect variations in all these dimensions. Progress in understanding socially biased learning in nonhuman species will be aided by the development of appropriately detailed models of the richly interconnected processes affecting learning. | ||||
| Address | Psychology Department, University of Georgia, Athens, Georgia 30602, USA. doree@uga.edu | ||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1543-4494 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:15161138 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 828 | ||
| Permanent link to this record | |||||
| Author | Hall, C.A.; Cassaday, H.J.; Derrington, A.M. | ||||
| Title | The effect of stimulus height on visual discrimination in horses | Type |
Journal Article | ||
| Year | 2003 | Publication | Journal of Animal Science | Abbreviated Journal | J. Anim Sci. |
| Volume | 81 | Issue | 7 | Pages | 1715-1720 |
| Keywords | Animals; *Discrimination Learning/physiology; Female; Horses/physiology/*psychology; Male; Orientation; *Photic Stimulation; Vision/*physiology | ||||
| Abstract | This study investigated the effect of stimulus height on the ability of horses to learn a simple visual discrimination task. Eight horses were trained to perform a two-choice, black/white discrimination with stimuli presented at one of two heights: ground level or at a height of 70 cm from the ground. The height at which the stimuli were presented was alternated from one session to the next. All trials within a single session were presented at the same height. The criterion for learning was four consecutive sessions of 70% correct responses. Performance was found to be better when stimuli were presented at ground level with respect to the number of trials taken to reach the criterion (P < 0.05), percentage of correct first choices (P < 0.01), and repeated errors made (P < 0.01). Thus, training horses to carry out tasks of visual discrimination could be enhanced by placing the stimuli on the ground. In addition, the results of the present study suggest that the visual appearance of ground surfaces is an important factor in both horse management and training. | ||||
| Address | School of Land-based Studies, Nottingham Trent University, Brackenhurst College Campus, Southwell, Nottinghamshire, England NG25 0QF. carol.hall@ntu.ac.uk | ||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-8812 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:12854807 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 835 | ||
| Permanent link to this record | |||||
| Author | Harman, A.M.; Moore, S.; Hoskins, R.; Keller, P. | ||||
| Title | Horse vision and an explanation for the visual behaviour originally explained by the 'ramp retina' | Type |
Journal Article | ||
| Year | 1999 | Publication | Equine veterinary journal | Abbreviated Journal | Equine Vet J |
| Volume | 31 | Issue | 5 | Pages | 384-390 |
| Keywords | Animals; Behavior, Animal; Cell Count; Eye/*anatomy & histology; Ganglia, Sensory/cytology; Horses/*physiology; Refractive Errors/veterinary; Retina/cytology/*physiology; Vision/*physiology; Visual Acuity; Visual Fields | ||||
| Abstract | Here we provide confirmation that the 'ramp retina' of the horse, once thought to result in head rotating visual behaviour, does not exist. We found a 9% variation in axial length of the eye between the streak region and the dorsal periphery. However, the difference was in the opposite direction to that proposed for the 'ramp retina'. Furthermore, acuity in the narrow, intense visual streak in the inferior retina is 16.5 cycles per degree compared with 2.7 cycles per degree in the periphery. Therefore, it is improbable that the horse rotates its head to focus onto the peripheral retina. Rather, the horse rotates the nose up high to observe distant objects because binocular overlap is oriented down the nose, with a blind area directly in front of the forehead. | ||||
| Address | Department of Psychology, University of Western Australia, Nedlands, Australia | ||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0425-1644 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:10505953 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 836 | ||
| Permanent link to this record | |||||
| Author | Mills, D.S. | ||||
| Title | Applying learning theory to the management of the horse: the difference between getting it right and getting it wrong | Type |
Journal Article | ||
| Year | 1998 | Publication | Equine veterinary journal. Supplement | Abbreviated Journal | Equine Vet J Suppl |
| Volume | Issue | 27 | Pages | 44-48 | |
| Keywords | Animals; *Behavior, Animal; Horses/*psychology; *Learning; Reinforcement (Psychology) | ||||
| Abstract | Horses constantly modify their behaviour as a result of experience. This involves the creation of an association between events or stimuli. The influence of people on the modification and generation of certain behaviour patterns extends beyond the intentional training of the horse. The impact of any action depends on how it is perceived by the horse, rather than the motive of the handler. Negative and positive reinforcement increase the probability of specific behaviours recurring i.e. strengthen the association between events, whereas punishment reduces the probable recurrence of a behaviour without providing specific information about the desired alternative. In this paper the term 'punishers' is used to refer to the physical aids, such as a whip or crop, which may be used to bring about the process of punishment. However, if their application ceases when a specific behaviour occurs they may negatively reinforce that action. Intended 'punishers' may also be rewarding (e.g. for attention seeking behaviour). Therefore, contingency factors (which define the relationship between stimuli, such as the level of reinforcement), contiguity factors (which describe the proximity of events in space or time) and choice of reinforcing stimuli are critical in determining the rate of learning. The many problems associated with the application of punishment in practice lead to confusion by both horse and handler and, possibly, abuse of the former. Most behaviour problems relate to handling and management of the horse and can be avoided or treated with a proper analysis of the factors influencing the behaviour. | ||||
| Address | De Montfort University Lincoln, School of Agriculture and Horticulture, Caythorpe, Lincs., UK | ||||
| Corporate Author | Thesis | ||||
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| Language | English | Summary Language | Original Title | ||
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| ISSN | ISBN | Medium | |||
| Area | Expedition | Conference | |||
| Notes | PMID:10485004 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 845 | ||
| Permanent link to this record | |||||
| Author | Cooper, J.J. | ||||
| Title | Comparative learning theory and its application in the training of horses | Type |
Journal Article | ||
| Year | 1998 | Publication | Equine veterinary journal. Supplement | Abbreviated Journal | Equine Vet J Suppl |
| Volume | Issue | 27 | Pages | 39-43 | |
| Keywords | Animals; *Behavior, Animal; Conditioning (Psychology); Horses/*psychology; *Learning; Reinforcement (Psychology) | ||||
| Abstract | Training can best be explained as a process that occurs through stimulus-response-reinforcement chains, whereby animals are conditioned to associate cues in their environment, with specific behavioural responses and their rewarding consequences. Research into learning in horses has concentrated on their powers of discrimination and on primary positive reinforcement schedules, where the correct response is paired with a desirable consequence such as food. In contrast, a number of other learning processes that are used in training have been widely studied in other species, but have received little scientific investigation in the horse. These include: negative reinforcement, where performance of the correct response is followed by removal of, or decrease in, intensity of a unpleasant stimulus; punishment, where an incorrect response is paired with an undesirable consequence, but without consistent prior warning; secondary conditioning, where a natural primary reinforcer such as food is closely associated with an arbitrary secondary reinforcer such as vocal praise; and variable or partial conditioning, where once the correct response has been learnt, reinforcement is presented according to an intermittent schedule to increase resistance to extinction outside of training. | ||||
| Address | Department of Zoology, University of Oxford, UK | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Medium | |||
| Area | Expedition | Conference | |||
| Notes | PMID:10485003 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 846 | ||
| Permanent link to this record | |||||