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Author Harcourt, J.L.; Ang, T.Z.; Sweetman, G.; Johnstone, R.A.; Manica, A. url  doi
openurl 
  Title Social feedback and the emergence of leaders and followers Type Journal Article
  Year 2009 Publication Current Biology : CB Abbreviated Journal Curr Biol  
  Volume 19 Issue 3 Pages 248-252  
  Keywords Analysis of Variance; Animals; Appetitive Behavior/physiology; *Feedback; Great Britain; *Leadership; Markov Chains; Models, Biological; Monte Carlo Method; Smegmamorpha/*physiology; *Social Behavior; Video Recording  
  Abstract In many animal groups, certain individuals consistently appear at the forefront of coordinated movements [1-4]. How such leaders emerge is poorly understood [5, 6]. Here, we show that in pairs of sticklebacks, Gasterosteus aculeatus, leadership arises from individual differences in the way that fish respond to their partner's movements. Having first established that individuals differed in their propensity to leave cover in order to look for food, we randomly paired fish of varying boldness, and we used a Markov Chain model to infer the individual rules underlying their joint behavior. Both fish in a pair responded to each other's movements-each was more likely to leave cover if the other was already out and to return if the other had already returned. However, we found that bolder individuals displayed greater initiative and were less responsive to their partners, whereas shyer individuals displayed less initiative but followed their partners more faithfully; they also, as followers, elicited greater leadership tendencies in their bold partners. We conclude that leadership in this case is reinforced by positive social feedback.  
  Address Department of Zoology, University of Cambridge, Cambridge, UK  
  Corporate Author Thesis  
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  Language English 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:19185497 Approved no  
  Call Number Equine Behaviour @ team @ Serial 5123  
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Author Gácsi, M.; Kara, E.; Belényi, B.; Topál, J.; Miklósi, Á. url  doi
openurl 
  Title The effect of development and individual differences in pointing comprehension of dogs Type Journal Article
  Year 2009 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 12 Issue 3 Pages 471-479  
  Keywords Age Factors; Analysis of Variance; Animals; *Association Learning; Attention; Chi-Square Distribution; Choice Behavior; *Comprehension; *Concept Formation; Dogs/*psychology; Female; *Gestures; Humans; Male; Orientation; Statistics, Nonparametric  
  Abstract In spite of the rather different procedures actually used in comparative studies to test the ability of different species to rely on the human pointing gesture, there is no debate on the high performance of dogs in such tasks. Very little is known, however, on the course through which they acquire this ability or the probable factors influencing the process. Important developmental questions have remained unsolved and also some methodological concerns should be addressed before we can convincingly argue for one interpretation or another. In this study we tested 180 dogs of different age (from 2 months to adults) to investigate their performance in the human distal momentary pointing gesture. The results, analyzed at both the group and the individual levels, showed no difference in the performance according to age, indicating that in dogs the comprehension of the human pointing may require only very limited and rapid early learning to fully develop. Interestingly, neither the keeping conditions nor the time spent in active interaction with the owner, and not even some special (agility) training for using human visual cues, had significant effect on the success and explained individual differences. The performance of the dogs was rather stable over time: during the 20 trials within a session and even when subsamples of different age were repeatedly tested. Considering that in spite of the general success at the group level, more than half of the dogs were not successful at the individual level, we revealed alternative “decision-making rules” other than following the pointing gesture of the experimenter.  
  Address Department of Ethology, Eotvos University, Budapest, Hungary. gm.art@t-online.hu  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1435-9456 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:19130102 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4969  
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Author Soproni, K.; Miklósi, Á.; Topál, J.; Csányi, V. url  doi
openurl 
  Title Dogs' (Canis familiaris) responsiveness to human pointing gestures Type Journal Article
  Year 2002 Publication Journal of Comparative Psychology (Washington, D.C. : 1983) Abbreviated Journal J Comp Psychol  
  Volume 116 Issue 1 Pages 27-34  
  Keywords Analysis of Variance; Animals; *Behavior, Animal; Choice Behavior; Dogs/*psychology; Female; Gestures; Male; *Recognition (Psychology); Species Specificity  
  Abstract In a series of 3 experiments, dogs (Canis familiaris) were presented with variations of the human pointing gesture: gestures with reversed direction of movement, cross-pointing, and different arm extensions. Dogs performed at above chance level if they could see the hand (and index finger) protruding from the human body contour. If these minimum requirements were not accessible, dogs still could rely on the body position of the signaler. The direction of movement of the pointing arm did not influence the performance. In summary, these observations suggest that dogs are able to rely on relatively novel gestural forms of the human communicative pointing gesture and that they are able to comprehend to some extent the referential nature of human pointing.  
  Address Department of Ethology, Eotvos Lorand University, Budapest, Hungary. krisztinasoproni@hotmail.com  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0735-7036 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:11926681 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4962  
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Author Moses, S.N.; Villate, C.; Ryan, J.D. doi  openurl
  Title An investigation of learning strategy supporting transitive inference performance in humans compared to other species Type Journal Article
  Year 2006 Publication Neuropsychologia Abbreviated Journal Neuropsychologia  
  Volume 44 Issue 8 Pages 1370-1387  
  Keywords Adult; Analysis of Variance; Association Learning/*physiology; *Cognition; *Concept Formation; Female; Humans; *Logic; Male; Pattern Recognition, Visual/physiology; Photic Stimulation/methods; Reaction Time/physiology  
  Abstract Generalizations about neural function are often drawn from non-human animal models to human cognition, however, the assumption of cross-species conservation may sometimes be invalid. Humans may use different strategies mediated by alternative structures, or similar structures may operate differently within the context of the human brain. The transitive inference problem, considered a hallmark of logical reasoning, can be solved by non-human species via associative learning rather than logic. We tested whether humans use similar strategies to other species for transitive inference. Results are crucial for evaluating the validity of widely accepted assumptions of similar neural substrates underlying performance in humans and other animals. Here we show that successful transitive inference in humans is unrelated to use of associative learning strategies and is associated with ability to report the hierarchical relationship among stimuli. Our work stipulates that cross-species generalizations must be interpreted cautiously, since performance on the same task may be mediated by different strategies and/or neural systems.  
  Address Rotman Research Institute, Baycrest Centre for Geriatric Care, Toronto, Canada. smoses@rotman-baycrest.on.ca  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-3932 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16503340 Approved no  
  Call Number refbase @ user @ Serial 153  
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Author Suzuki, Y.; Toquenaga, Y. doi  openurl
  Title Effects of information and group structure on evolution of altruism: analysis of two-score model by covariance and contextual analyses Type Journal Article
  Year 2005 Publication Journal of theoretical biology Abbreviated Journal J. Theor. Biol.  
  Volume 232 Issue 2 Pages 191-201  
  Keywords *Altruism; Analysis of Variance; *Communication; Cooperative Behavior; *Evolution; Game Theory; *Group Structure; Humans; Models, Genetic; Models, Psychological; Selection (Genetics); Trust  
  Abstract An altruistic individual has to gamble on cooperation to a stranger because it does not know whether the stranger is trustworthy before direct interaction. Nowak and Sigmund (Nature 393 (1998a) 573; J. Theor. Biol. 194 (1998b) 561) presented a new theoretical framework of indirect reciprocal altruism by image scoring game where all individuals are informed about a partner's behavior from its image score without direct interaction. Interestingly, in a simplified version of the image scoring game, the evolutionarily stability condition for altruism became a similar form of Hamilton's rule, i.e. inequality that the probability of getting correct information is more than the ratio of cost to benefit. Since the Hamilton's rule was derived by evolutionarily stable analysis, the evolutionary meaning of the probability of getting correct information has not been clearly examined in terms of kin and group selection. In this study, we applied covariance analysis to the two-score model for deriving the Hamilton's rule. We confirmed that the probability of getting correct information was proportional to the bias of altruistic interactions caused by using information about a partner's image score. The Hamilton's rule was dependent on the number of game bouts even though the information reduced the risk of cooperation to selfish one at the first encounter. In addition, we incorporated group structure to the two-score model to examine whether the probability of getting correct information affect selection for altruism by group selection. We calculated a Hamilton's rule of group selection by contextual analysis. Group selection is very effective when either the probability of getting correct information or that of future interaction, or both are low. The two Hamilton's rules derived by covariance and contextual analyses demonstrated the effects of information and group structure on the evolution of altruism. We inferred that information about a partner's behavior and group structure can produce flexible pathways for the evolution of altruism.  
  Address Integrative Environmental Sciences, Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Ten-Nou-Dai, Tsukuba, Ibaraki 305-8572, Japan. yukari@pe.ies.life.tsukuba.ac.jp  
  Corporate Author Thesis  
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  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:15530489 Approved no  
  Call Number refbase @ user @ Serial 556  
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Author Palmer, M.E.; Calve, M.R.; Adamo, S.A. doi  openurl
  Title Response of female cuttlefish Sepia officinalis (Cephalopoda) to mirrors and conspecifics: evidence for signaling in female cuttlefish Type Journal Article
  Year 2006 Publication Animal cognition Abbreviated Journal Anim. Cogn.  
  Volume 9 Issue 2 Pages 151-155  
  Keywords Analysis of Variance; *Animal Communication; Animals; Bias (Epidemiology); Female; Male; Pigmentation/*physiology; Recognition (Psychology)/*physiology; Sepia/*physiology; Visual Perception/*physiology  
  Abstract Cuttlefish have a large repertoire of body patterns that are used for camouflage and interspecific signaling. Intraspecific signaling by male cuttlefish has been well documented but studies on signaling by females are lacking. We found that females displayed a newly described body pattern termed Splotch toward their mirror image and female conspecifics, but not to males, prey or inanimate objects. Female cuttlefish may use the Splotch body pattern as an intraspecific signal, possibly to reduce agonistic interactions. The ability of females to produce a consistent body pattern in response to conspecifics and mirrors suggests that they can recognize same-sex conspecifics using visual cues, despite the lack of sexual dimorphism visible to human observers.  
  Address Dorset Environmental Science Centre, Dorset, ON, Canada, P0A 1E0  
  Corporate Author Thesis  
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  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:16408230 Approved no  
  Call Number Admin @ knut @ Serial 16  
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Author Brosnan, S.F.; Schiff, H.C.; de Waal, F.B.M. doi  openurl
  Title Tolerance for inequity may increase with social closeness in chimpanzees Type Journal Article
  Year 2005 Publication Proceedings. Biological sciences / The Royal Society Abbreviated Journal Proc Biol Sci  
  Volume 272 Issue 1560 Pages 253-258  
  Keywords Analysis of Variance; Animals; *Attitude; Group Processes; Pan troglodytes/*psychology; Reward; *Social Behavior; Socioeconomic Factors  
  Abstract Economic decision-making depends on our social environment. Humans tend to respond differently to inequity in close relationships, yet we know little about the potential for such variation in other species. We examine responses to inequity in several groups of chimpanzees (Pan troglodytes) in a paradigm similar to that used previously in capuchin monkeys (Cebus apella). We demonstrate that, like capuchin monkeys, chimpanzees show a response to inequity of rewards that is based upon the partner receiving the reward rather than the presence of the reward alone. However, we also found a great amount of variation between groups tested, indicating that chimpanzees, like people, respond to inequity in a variable manner, which we speculate could be caused by such variables as group size, the social closeness of the group (as reflected in length of time that the group has been together) and group-specific traditions.  
  Address Yerkes National Primate Research Center, Emory University, 954 North Gatewood Drive, Atlanta, GA 30329, USA. sbrosna@emory.edu  
  Corporate Author Thesis  
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  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:15705549 Approved no  
  Call Number refbase @ user @ Serial 169  
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Author de Waal, F.B.M.; Dindo, M.; Freeman, C.A.; Hall, M.J. doi  openurl
  Title The monkey in the mirror: hardly a stranger Type Journal Article
  Year 2005 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.  
  Volume 102 Issue 32 Pages 11140-11147  
  Keywords Analysis of Variance; Animals; Cebus/*physiology; *Discrimination (Psychology); Empathy; Female; Male; Observation; *Recognition (Psychology); *Self Concept; Sex Factors  
  Abstract It is widely assumed that monkeys see a stranger in the mirror, whereas apes and humans recognize themselves. In this study, we question the former assumption by using a detailed comparison of how monkeys respond to mirrors versus live individuals. Eight adult female and six adult male brown capuchin monkeys (Cebus apella) were exposed twice to three conditions: (i) a familiar same-sex partner, (ii) an unfamiliar same-sex partner, and (iii) a mirror. Females showed more eye contact and friendly behavior and fewer signs of anxiety in front of a mirror than they did when exposed to an unfamiliar partner. Males showed greater ambiguity, but they too reacted differently to mirrors and strangers. Discrimination between conditions was immediate, and blind coders were able to tell the difference between monkeys under the three conditions. Capuchins thus seem to recognize their reflection in the mirror as special, and they may not confuse it with an actual conspecific. Possibly, they reach a level of self-other distinction intermediate between seeing their mirror image as other and recognizing it as self.  
  Address Living Links Center, Emory University, Atlanta, GA 30322, USA. dewaal@emory.edu  
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  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:16055557 Approved no  
  Call Number refbase @ user @ Serial 164  
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Author Rosa, P.A.J.; Azevedo, A.M.; Aires-Barros, M.R. doi  openurl
  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  
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  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 Brosnan, S.F.; de Waal, F.B.M. doi  openurl
  Title Responses to a simple barter task in chimpanzees, Pan troglodytes Type Journal Article
  Year 2005 Publication Primates Abbreviated Journal Primates  
  Volume 46 Issue 3 Pages 173-182  
  Keywords Analysis of Variance; Animals; Choice Behavior/*physiology; Conditioning (Psychology)/physiology; Learning/*physiology; Pan troglodytes/*physiology; Reward; Sex Factors; *Social Behavior; *Token Economy  
  Abstract Chimpanzees (Pan troglodytes) frequently participate in social exchange involving multiple goods and services of variable value, yet they have not been tested in a formalized situation to see whether they can barter using multiple tokens and rewards. We set up a simple barter economy with two tokens and two associated rewards and tested chimpanzees on their ability to obtain rewards by returning the matching token in situations in which their access to tokens was unlimited or limited. Chimpanzees easily learned to associate value with the tokens, as expected, and did barter, but followed a simple strategy of favoring the higher-value token, regardless of the reward proffered, instead of a more complex but more effective strategy of returning the token that matched the reward. This response is similar to that shown by capuchin monkeys in our previous study. We speculate that this response, while not ideal, may be sufficient to allow for stability of the social exchange system in these primates, and that the importance of social barter to both species may have led to this convergence of strategies.  
  Address Living Links, Yerkes National Primate Research Center, Atlanta, GA 30322, USA. sbrosna@emory.edu  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0032-8332 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15824938 Approved no  
  Call Number refbase @ user @ Serial 167  
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