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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.
	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
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	Author	Waite, T.A.
	Title	Interruptions improve choice performance in gray jays: prolonged information processing versus minimization of costly errors			Type	Journal Article
	Year	2002	Publication	Animal Cognition	Abbreviated Journal	Anim. Cogn.
	Volume	5	Issue	4	Pages	209-214
	Keywords	Animals; Behavior, Animal; Choice Behavior; Female; Learning; Male; Models, Biological; Motivation; Reinforcement Schedule; Songbirds/*physiology; Time Factors
	Abstract	Under the assumption that selection favors minimization of costly errors, erroneous choice may be common when its fitness cost is low. According to an adaptive-choice model, this cost depends on the rate at which an animal encounters the choice: the higher this rate, the smaller the cost of choosing a less valuable option. Errors should thus be more common when interruptions to foraging are shorter. A previous experiment supported this prediction: gray jays, Perisoreus canadensis, were more error prone when subjected to shorter delays to access to food rewards. This pattern, though, is also predicted by an attentional-constraints model. Because the subjects were able to inspect the rewards during delays, their improved performance when subjected to longer delays could have been a byproduct of the experimentally prolonged opportunity for information processing. To evaluate this possibility, a follow-up experiment manipulated both delay to access and whether rewards could be inspected during delays. Depriving jays of the opportunity to inspect rewards (using opaque lids) induced only a small, nonsignificant increase in error rate. This effect was independent of length of delay and so the jays' improved performance when subjected to longer delays was not simply a byproduct of prolonged information processing. More definitively, even when the jays were prevented from inspecting rewards during delays, their performance improved when subjected to longer delays. The findings are thus consistent with the adaptive-choice model.
	Address	Department of Evolution, Ecology, and Organismal Biology, Ohio State University, 1735 Neil Avenue, Columbus, OH 43210-1293, USA. waite.1@osu.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	1435-9448	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:12461598			Approved	no
	Call Number	Equine Behaviour @ team @			Serial	2592
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	Author	Viscido, S.V.; Miller, M.; Wethey, D.S.
	Title	The response of a selfish herd to an attack from outside the group perimeter			Type	Journal Article
	Year	2001	Publication	Journal of theoretical biology	Abbreviated Journal	J. Theor. Biol.
	Volume	208	Issue	3	Pages	315-328
	Keywords	Animals; Behavior, Animal; Computer Simulation; Models, Biological; *Movement; Predatory Behavior
	Abstract	According to the selfish herd hypothesis, animals can decrease predation risk by moving toward one another if the predator can appear anywhere and will attack the nearest target. Previous studies have shown that aggregations can form using simple movement rules designed to decrease each animal's Domain of Danger. However, if the predator attacks from outside the group's perimeter, these simple movement rules might not lead to aggregation. To test whether simple selfish movement rules would decrease predation risk for those situations when the predator attacks from outside the flock perimeter, we constructed a computer model that allowed flocks of 75 simulated fiddler crabs to react to one another, and to a predator attacking from 7 m away. We attacked simulated crab flocks with predators of different sizes and attack speeds, and computed relative predation risk after 120 time steps. Final trajectories showed flight toward the center of the flock, but curving away from the predator. Path curvature depended on the predator's size and approach speed. The average crab experienced a greater decrease in predation risk when the predator was small or slow moving. Regardless of the predator's size and speed, however, predation risk always decreased as long as crabs took their flock-mates into account. We conclude that, even when flight away from an external predator occurs, the selfish avoidance of danger can lead to aggregation.
	Address	Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, U.S.A. viscido@u.washington.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	0022-5193	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:11207093			Approved	no
	Call Number	refbase @ user @			Serial	555
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	Author	Izar, P.; Ferreira, R.G.; Sato, T.
	Title	Describing the organization of dominance relationships by dominance-directed tree method			Type	Journal Article
	Year	2006	Publication	American journal of primatology	Abbreviated Journal	Am. J. Primatol.
	Volume	68	Issue	2	Pages	189-207
	Keywords	Animals; Cebus/physiology; Models, Biological; Social Dominance
	Abstract	Methods to describe dominance hierarchies are a key tool in primatology studies. Most current methods are appropriate for analyzing linear and near-linear hierarchies; however, more complex structures are common in primate groups. We propose a method termed “dominance-directed tree.” This method is based on graph theory and set theory to analyze dominance relationships in social groups. The method constructs a transitive matrix by imposing transitivity to the dominance matrix and produces a graphical representation of the dominance relationships, which allows an easy visualization of the hierarchical position of the individuals, or subsets of individuals. The method is also able to detect partial and complete hierarchies, and to describe situations in which hierarchical and nonhierarchical principles operate. To illustrate the method, we apply a dominance tree analysis to artificial data and empirical data from a group of Cebus apella.
	Address	Department of Experimental Psychology, University of Sao Paulo, Brazil. patrizar@usp.br
	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	0275-2565	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:16429416			Approved	no
	Call Number	refbase @ user @			Serial	723
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	Author	Viscido, S.V.; Miller, M.; Wethey, D.S.
	Title	The dilemma of the selfish herd: the search for a realistic movement rule			Type	Journal Article
	Year	2002	Publication	Journal of theoretical biology	Abbreviated Journal	J. Theor. Biol.
	Volume	217	Issue	2	Pages	183-194
	Keywords	Animals; Behavior, Animal; Mass Behavior; Models, Biological; *Motor Activity; Predatory Behavior
	Abstract	The selfish herd hypothesis predicts that aggregations form because individuals move toward one another to minimize their own predation risk. The “dilemma of the selfish herd” is that movement rules that are easy for individuals to follow, fail to produce true aggregations, while rules that produce aggregations require individual behavior so complex that one may doubt most animals can follow them. If natural selection at the individual level is responsible for herding behavior, a solution to the dilemma must exist. Using computer simulations, we examined four different movement rules. Relative predation risk was different for all four movement rules (p<0.05). We defined three criteria for measuring the quality of a movement rule. A good movement rule should (a) be statistically likely to benefit an individual that follows it, (b) be something we can imagine most animals are capable of following, and (c) result in a centrally compact flock. The local crowded horizon rule, which allowed individuals to take the positions of many flock-mates into account, but decreased the influence of flock-mates with distance, best satisfied these criteria. The local crowded horizon rule was very sensitive to the animal's perceptive ability. Therefore, the animal's ability to detect its neighbors is an important factor in the dynamics of group formation.
	Address	Department of Biological Sciences, University of South Carolina, Columbia, SC, 29208, USA. viscido@u.washington.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	0022-5193	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:12202112			Approved	no
	Call Number	refbase @ user @			Serial	554
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	Author	Bergstrom, C.T.; Lachmann, M.
	Title	Signaling among relatives. III. Talk is cheap			Type	Journal Article
	Year	1998	Publication	Proceedings of the National Academy of Sciences of the United States of America	Abbreviated Journal	Proc. Natl. Acad. Sci. U.S.A.
	Volume	95	Issue	9	Pages	5100-5105
	Keywords	Animal Communication; Animals; Costs and Cost Analysis; *Evolution; Interpersonal Relations; Models, Biological
	Abstract	The Sir Philip Sidney game has been used by numerous authors to show how signal cost can facilitate honest signaling among relatives. Here, we demonstrate that, in this game, honest cost-free signals are possible as well, under very general conditions. Moreover, these cost-free signals are better for all participants than the previously explored alternatives. Recent empirical evidence suggests that begging is energetically inexpensive for nestling birds; this finding led some researchers to question the applicability of the costly signaling framework to nestling begging. Our results show that cost-free or inexpensive signals, as observed empirically, fall within the framework of signaling theory.
	Address	Department of Biological Sciences, Stanford University, Stanford, CA 94305, USA. carl@charles.stanford.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	0027-8424	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:9560235			Approved	no
	Call Number	refbase @ user @			Serial	561
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	Author	Dubois, F.; Giraldeau, L.-A.; Hamilton, I.M.; Grant, J.W.A.; Lefebvre, L.
	Title	Distraction sneakers decrease the expected level of aggression within groups: a game-theoretic model			Type	Journal Article
	Year	2004	Publication	The American Naturalist	Abbreviated Journal	Am Nat
	Volume	164	Issue	2	Pages	E32-45
	Keywords	Aggression; Animals; Behavior, Animal/physiology; Columbidae/physiology; Competitive Behavior; Cooperative Behavior; Game Theory; Hawks/*physiology; Models, Biological
	Abstract	Hawk-dove games have been extensively used to predict the conditions under which group-living animals should defend their resources against potential usurpers. Typically, game-theoretic models on aggression consider that resource defense may entail energetic and injury costs. However, intruders may also take advantage of owners who are busy fighting to sneak access to unguarded resources, imposing thereby an additional cost on the use of the escalated hawk strategy. In this article we modify the two-strategy hawk-dove game into a three-strategy hawk-dove-sneaker game that incorporates a distraction-sneaking tactic, allowing us to explore its consequences on the expected level of aggression within groups. Our model predicts a lower proportion of hawks and hence lower frequencies of aggressive interactions within groups than do previous two-strategy hawk-dove games. The extent to which distraction sneakers decrease the frequency of aggression within groups, however, depends on whether they search only for opportunities to join resources uncovered by other group members or for both unchallenged resources and opportunities to usurp.
	Address	Departement des Sciences Biologiques, Universite du Quebec a Montreal, Case postale 8888 Succursale Centre-Ville, Montreal, Quebec H3C 3P8, Canada. frede_dubois@yahoo.fr
	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	1537-5323	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:15278850			Approved	no
	Call Number				Serial	2130
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	Author	Reimers, M.; Schwarzenberger, F.; Preuschoft, S.
	Title	Rehabilitation of research chimpanzees: stress and coping after long-term isolation			Type	Journal Article
	Year	2007	Publication	Hormones and Behavior	Abbreviated Journal	Horm Behav
	Volume	51	Issue	3	Pages	428-435
	Keywords	Adaptation, Psychological/physiology; Animals; Animals, Laboratory; Exploratory Behavior; Hydrocortisone/analysis/metabolism; Male; Models, Biological; Pan troglodytes; Social Dominance; Social Environment; Social Isolation/psychology; Stress/*rehabilitation/veterinary; Time
	Abstract	We report on the permanent retirement of chimpanzees from biomedical research and on resocialization after long-term social isolation. Our aim was to investigate to what extent behavioral and endocrine measures of stress in deprived laboratory chimpanzees can be improved by a more species-typical social life style. Personality in terms of novelty responses, social dominance after resocialization and hormonal stress susceptibility were affected by the onset of maternal separation of infant chimpanzees and duration of deprivation. Chimpanzees, who were separated from their mothers at a younger age and kept in isolation for more years appeared to be more timid personalities, less socially active, less dominant and more susceptible to stress, as compared to chimpanzees with a less severe deprivation history. However, permanent retirement from biomedical research in combination with therapeutic resocialization maximizing chimpanzees' situation control resulted in reduced fecal cortisol metabolite levels. Our results indicate that chimpanzees can recover from severe social deprivation, and may experience resocialization as less stressful than solitary housing.
	Address	Department of Natural Sciences, Institute of Biochemistry, University of Veterinary Medicine, Veterinarplatz 1, 1210 Vienna, Austria. reimers@wild-vet.at
	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	0018-506X	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:17292368			Approved	no
	Call Number	Equine Behaviour @ team @			Serial	4188
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	Author	Rosa, P.A.J.; Azevedo, A.M.; Aires-Barros, M.R.
	Title	Application of central composite design to the optimisation of aqueous two-phase extraction of human antibodies			Type	Journal Article
	Year	2007	Publication	Journal of Chromatography. A	Abbreviated Journal	J Chromatogr A
	Volume	1141	Issue	1	Pages	50-60
	Keywords	Analysis of Variance; Animals; Antibodies/chemistry/isolation & purification; Buffers; Chemical Fractionation/*methods; Horses; Humans; Hydrophobicity; Isoelectric Point; Models, Biological; Molecular Weight; Myoglobin/chemistry/isolation & purification; Osmolar Concentration; Phase Transition; Polyethylene Glycols; Serum Albumin/chemistry/isolation & purification; Sodium Chloride
	Abstract	The partition of human antibodies in aqueous two-phase systems (ATPSs) of polyethylene glycol (PEG) and phosphate was systematically studied using first pure proteins systems and then an artificial mixture of proteins containing 1mg/ml human immunoglobulin G (IgG), 10mg/ml serum albumin and 2mg/ml myoglobin. Preliminary results obtained using pure proteins systems indicated that the PEG molecular weight and concentration, the pH value and the salts concentration had a pronounced effect on the partitioning behaviour of all proteins. For high ionic strengths and pH values higher than the isoelectric point (pI) of the contaminant proteins, IgG could be selectively recovered on the top phase. According to these results, a face centred composite design was performed in order to optimise the purification of IgG from the mixture of proteins. The optimal conditions for the isolation of IgG were observed for high concentrations of NaCl and low concentrations of both phase forming components. The best purification was achieved using an ATPS containing 8% (w/w) PEG 3350, 10% (w/w) phosphate pH 6 and 15% (w/w) NaCl. A recovery yield of 101+/-7%, a purity of 99+/-0% and a yield of native IgG of 97+/-4% were obtained. Back extraction studies of IgG to a new phosphate phase were performed and higher yields were obtained using 10% phosphate buffer at pH 6. The total extraction yield was 76% and the purity 100%.
	Address	IBB Institute for Biotechnology and Bioengineering, Centre for Biological and Chemical Engineering, Instituto Superior Tecnico, Av Rovisco Pais, 1049-001 Lisbon, Portugal
	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	0021-9673	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:17196214			Approved	no
	Call Number				Serial	1842
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	Author	Tobin, T.; Combie, J.D.
	Title	Performance testing in horses: a review of the role of simple behavioral models in the design of performance experiments			Type	Journal Article
	Year	1982	Publication	Journal of Veterinary Pharmacology and Therapeutics	Abbreviated Journal	J Vet Pharmacol Ther
	Volume	5	Issue	2	Pages	105-118
	Keywords	Analgesics, Opioid/pharmacology; Animals; Apomorphine/pharmacology; Behavior, Animal/drug effects; Dose-Response Relationship, Drug; Fentanyl/pharmacology; Horses/physiology; Methylphenidate/pharmacology; *Models, Biological; Motor Activity/drug effects
	Abstract
	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	0140-7783	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:6125601			Approved	no
	Call Number	refbase @ user @			Serial	1957
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