Equine and Animal Cognition Reference Database -- Query Results

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Author	Rands, S.A.; Cowlishaw, G.; Pettifor, R.A.; Rowcliffe, J.M.; Johnstone, R.A.
Title	The emergence of leaders and followers in foraging pairs when the qualities of individuals differ			Type	Journal Article
Year	2008	Publication	BMC Evolutionary Biology	Abbreviated Journal	BMC Evol Biol
Volume	8	Issue		Pages	51
Keywords	Animals; Feeding Behavior; Food Chain; Models, Biological; Social Dominance
Abstract	BACKGROUND: Foraging in groups offers animals a number of advantages, such as increasing their likelihood of finding food or detecting and avoiding predators. In order for a group to remain together, there has to be some degree of coordination of behaviour and movement between its members (which may in some cases be initiated by a decision-making leader, and in other cases may emerge as an underlying property of the group). For example, behavioural synchronisation is a phenomenon where animals within a group initiate and then continue to conduct identical behaviours, and has been characterised for a wide range of species. We examine how a pair of animals should behave using a state-dependent approach, and ask what conditions are likely to lead to behavioural synchronisation occurring, and whether one of the individuals is more likely to act as a leader. RESULTS: The model we describe considers how the energetic gain, metabolic requirements and predation risks faced by the individuals affect measures of their energetic state and behaviour (such as the degree of behavioural synchronisation seen within the pair, and the value to an individual of knowing the energetic state of its colleague). We explore how predictable changes in these measures are in response to changes in physiological requirements and predation risk. We also consider how these measures should change when the members of the pair are not identical in their metabolic requirements or their susceptibility to predation. We find that many of the changes seen in these measures are complex, especially when asymmetries exist between the members of the pair. CONCLUSION: Analyses are presented that demonstrate that, although these general patterns are robust, care needs to be taken when considering the effects of individual differences, as the relationship between individual differences and the resulting qualitative changes in behaviour may be complex. We discuss how these results are related to experimental observations, and how the model and its predictions could be extended.
Address	Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK. sean.rands@bristol.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	1471-2148	ISBN		Medium
Area		Expedition		Conference
Notes	PMID:18282297			Approved	no
Call Number	Equine Behaviour @ team @			Serial	5126
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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	Kiltie, R.A.; Fan, J.; Laine, A.F.
Title	A wavelet-based metric for visual texture discrimination with applications in evolutionary ecology			Type	Journal Article
Year	1995	Publication	Mathematical Biosciences	Abbreviated Journal	Math Biosci
Volume	126	Issue	1	Pages	21-39
Keywords	Animals; Carnivora; Ecology; Equidae; Evolution; Humans; Mathematics; Models, Biological; Moths; *Pattern Recognition, Visual; Pigmentation
Abstract	Much work on natural and sexual selection is concerned with the conspicuousness of visual patterns (textures) on animal and plant surfaces. Previous attempts by evolutionary biologists to quantify apparency of such textures have involved subjective estimates of conspicuousness or statistical analyses based on transect samples. We present a method based on wavelet analysis that avoids subjectivity and that uses more of the information in image textures than transects do. Like the human visual system for texture discrimination, and probably like that of other vertebrates, this method is based on localized analysis of orientation and frequency components of the patterns composing visual textures. As examples of the metric's utility, we present analyses of crypsis for tigers, zebras, and peppered moth morphs.
Address	Department of Zoology, University of Florida, Gainesville
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	0025-5564	ISBN		Medium
Area		Expedition		Conference
Notes	PMID:7696817			Approved	no
Call Number	Equine Behaviour @ team @			Serial	2660
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Author	McClearn, G.E.
Title	Behavioral genetics			Type	Journal Article
Year	1971	Publication	Behavioral Science	Abbreviated Journal	Behav Sci
Volume	16	Issue	1	Pages	64-81
Keywords	Amino Acid Metabolism, Inborn Errors; Animals; Aptitude; Behavior, Animal; Chromosome Aberrations; Cognition; Cytogenetics; Female; *Genetics, Behavioral; Genetics, Population; Humans; Intelligence; Mental Retardation; Mice; Models, Biological; Personality; Phenylketonurias; Pregnancy; Research; Schizophrenia; Sex Chromosome Aberrations; Twins
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	0005-7940	ISBN		Medium
Area		Expedition		Conference
Notes	PMID:5105941			Approved	no
Call Number	Equine Behaviour @ team @			Serial	4150
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Author	Mettke-Hofmann, C.; Gwinner, E.
Title	Long-term memory for a life on the move			Type	Journal Article
Year	2003	Publication	Proceedings of the National Academy of Sciences of the United States of America	Abbreviated Journal	Proc. Natl. Acad. Sci. U.S.A.
Volume	100	Issue	10	Pages	5863-5866
Keywords	Animals; Germany; Israel; Memory/physiology; Models, Biological; Periodicity; Songbirds/physiology
Abstract	Evidence is accumulating that cognitive abilities are shaped by the specific ecological conditions to which animals are exposed. Long-distance migratory birds may provide a striking example of this. Field observations have shown that, at least in some species, a substantial proportion of individuals return to the same breeding, wintering, and stopover sites in successive years. This observation suggests that migrants have evolved special cognitive abilities that enable them to accomplish these feats. Here we show that memory of a particular feeding site persisted for at least 12 months in a long-distance migrant, whereas a closely related nonmigrant could remember such a site for only 2 weeks. Thus, it seems that the migratory lifestyle has influenced the learning and memorizing capacities of migratory birds. These results build a bridge between field observations suggesting special memorization feats of migratory birds and previous neuroanatomical results from the same two species indicating an increase in relative hippocampal size from the first to the second year of life in the migrant but not in the nonmigrant.
Address	Max Planck Research Centre for Ornithology, Department of Biological Rhythms and Behaviour, Von-der-Tann-Strasse 7, 82346 Andechs, Germany. mettke-hofmann@erl.ornithol.mpg.de
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:12719527			Approved	no
Call Number	refbase @ user @			Serial	511
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Author	Brilot, B.O.; Johnstone, R.A.
Title	The limits to cost-free signalling of need between relatives			Type	Journal Article
Year	2003	Publication	Proceedings. Biological sciences / The Royal Society	Abbreviated Journal	Proc Biol Sci
Volume	270	Issue	1519	Pages	1055-1060
Keywords	Animal Communication; Animals; Birds/physiology; Models, Biological; Social Behavior
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.
Address	Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK. bob21@cam.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	0962-8452	ISBN		Medium
Area		Expedition		Conference
Notes	PMID:12803895			Approved	no
Call Number	refbase @ user @			Serial	558
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Author	Cameron, E.Z.
Title	Facultative adjustment of mammalian sex ratios in support of the Trivers-Willard hypothesis: evidence for a mechanism			Type	Journal Article
Year	2004	Publication	Proceedings. Biological sciences / The Royal Society	Abbreviated Journal	Proc Biol Sci
Volume	271	Issue	1549	Pages	1723-1728
Keywords	Age Factors; Animals; Body Constitution; Evolution; Female; Glucose/metabolism/physiology; Litter Size; Male; Mammals/physiology; Models, Biological; Reproduction/physiology; Seasons; Sex Factors; Sex Ratio; Time Factors
Abstract	Evolutionary theory predicts that mothers of different condition should adjust the birth sex ratio of their offspring in relation to future reproductive benefits. Published studies addressing variation in mammalian sex ratios have produced surprisingly contradictory results. Explaining the source of such variation has been a challenge for sex-ratio theory, not least because no mechanism for sex-ratio adjustment is known. I conducted a meta-analysis of previous mammalian sex-ratio studies to determine if there are any overall patterns in sex-ratio variation. The contradictory nature of previous results was confirmed. However, studies that investigated indices of condition around conception show almost unanimous support for the prediction that mothers in good condition bias their litters towards sons. Recent research on the role of glucose in reproductive functioning have shown that excess glucose favours the development of male blastocysts, providing a potential mechanism for sex-ratio variation in relation to maternal condition around conception. Furthermore, many of the conflicting results from studies on sex-ratio adjustment would be explained if glucose levels in utero during early cell division contributed to the determination of offspring sex ratios.
Address	Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria 0002, South Africa. ezcameron@zoology.up.ac.za
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	0962-8452	ISBN		Medium
Area		Expedition		Conference
Notes	PMID:15306293			Approved	no
Call Number	refbase @ user @			Serial	413
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Author	Zhou, W.-X.; Sornette, D.; Hill, R.A.; Dunbar, R.I.M.
Title	Discrete hierarchical organization of social group sizes			Type	Journal Article
Year	2005	Publication	Proceedings. Biological sciences / The Royal Society	Abbreviated Journal	Proc Biol Sci
Volume	272	Issue	1561	Pages	439-444
Keywords	Anthropology, Cultural; Group Structure; Humans; Models, Biological; Social Behavior; Social Environment
Abstract	The 'social brain hypothesis' for the evolution of large brains in primates has led to evidence for the coevolution of neocortical size and social group sizes, suggesting that there is a cognitive constraint on group size that depends, in some way, on the volume of neural material available for processing and synthesizing information on social relationships. More recently, work on both human and non-human primates has suggested that social groups are often hierarchically structured. We combine data on human grouping patterns in a comprehensive and systematic study. Using fractal analysis, we identify, with high statistical confidence, a discrete hierarchy of group sizes with a preferred scaling ratio close to three: rather than a single or a continuous spectrum of group sizes, humans spontaneously form groups of preferred sizes organized in a geometrical series approximating 3-5, 9-15, 30-45, etc. Such discrete scale invariance could be related to that identified in signatures of herding behaviour in financial markets and might reflect a hierarchical processing of social nearness by human brains.
Address	State Key Laboratory of Chemical Reaction Engineering, East China University of Science and Technology, Shanghai 200237, 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	0962-8452	ISBN		Medium
Area		Expedition		Conference
Notes	PMID:15734699			Approved	no
Call Number	refbase @ user @			Serial	549
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Author	Scheffer, M.; van Nes, E.H.
Title	Self-organized similarity, the evolutionary emergence of groups of similar species			Type	Journal Article
Year	2006	Publication	Proceedings of the National Academy of Sciences of the United States of America	Abbreviated Journal	Proc. Natl. Acad. Sci. U.S.A.
Volume	103	Issue	16	Pages	6230-6235
Keywords	Animals; Competitive Behavior; Ecosystem; Evolution; Models, Biological
Abstract	Ecologists have long been puzzled by the fact that there are so many similar species in nature. Here we show that self-organized clusters of look-a-likes may emerge spontaneously from coevolution of competitors. The explanation is that there are two alternative ways to survive together: being sufficiently different or being sufficiently similar. Using a model based on classical competition theory, we demonstrate a tendency for evolutionary emergence of regularly spaced lumps of similar species along a niche axis. Indeed, such lumpy patterns are commonly observed in size distributions of organisms ranging from algae, zooplankton, and beetles to birds and mammals, and could not be well explained by earlier theory. Our results suggest that these patterns may represent self-constructed niches emerging from competitive interactions. A corollary of our findings is that, whereas in species-poor communities sympatric speciation and invasion of open niches is possible, species-saturated communities may be characterized by convergent evolution and invasion by look-a-likes.
Address	Aquatic Ecology and Water Quality Management Group, Department of Environmental Sciences, Wageningen University, P.O. Box 8080, 6700 DD, Wageningen, The Netherlands. marten.scheffer@wur.nl
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:16585519			Approved	no
Call Number	refbase @ user @			Serial	510
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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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