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| Author | Galef BG, J.; Giraldeau, L.A. | ||||
| Title | Social influences on foraging in vertebrates: causal mechanisms and adaptive functions | Type | Journal Article | ||
| Year | 2001 | Publication | Animal Behaviour. | Abbreviated Journal | Anim. Behav. |
| Volume | 61 | Issue | 1 | Pages | 3-15 |
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| Abstract | We summarize 20 years of empirical and theoretical research on causes and functions of social influences on foraging by animals. We consider separately studies of social influence on when, where, what and how to eat. Implicit in discussion of the majority of studies is our assumption that social influences on foraging reflect a biasing of individual learning processes by social stimuli rather than action of independent social-learning mechanisms. Our review of theoretical approaches suggests that the majority of formally derived hypotheses concerning functions of social influence on foraging have not yet been tested adequately and many models are in need of further refinement. We also consider the importance to the future of the field of integrating 'top-down' and 'bottom-up' approaches to the study of social learning. Copyright 2001 The Association for the Study of Animal Behaviour. | ||||
| Address | Department of Psychology, McMaster University | ||||
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| Language | English | Summary Language | Original Title | ||
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ISSN  |
0003-3472 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:11170692 | Approved | no | ||
| Call Number | Serial | 2135 | |||
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| Author | Kudo, H.; Dunbar, R.I.M. | ||||
| Title | Neocortex size and social network size in primates | Type | Journal Article | ||
| Year | 2001 | Publication | Animal Behaviour. | Abbreviated Journal | Anim. Behav. |
| Volume | 62 | Issue | 4 | Pages | 711-722 |
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| Abstract | Primates use social grooming to service coalitions and it has been suggested that these directly affect the fitness of their members by allowing them to reduce the intrinsic costs associated with living in large groups. We tested two hypotheses about the size of grooming cliques that derive from this suggestion: (1) that grooming clique size should correlate with relative neocortex size and (2) that the size of grooming cliques should be proportional to the size of the groups they have to support. Both predictions were confirmed, although we show that, in respect of neocortex size, there are as many as four statistically distinct grades within the primates (including humans). Analysis of the patterns of grooming among males and females suggested that large primate social groups often consist of a set of smaller female subgroups (in some cases, matrilinearly based coalitions) that are linked by individual males. This may be because males insert themselves into the interstices between weakly bonded female subgroups rather than because they actually hold these subunits together. | ||||
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| ISSN |
0003-3472 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 4726 | ||
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| Author | Kasuya, E. | ||||
| Title | Mann-Whitney U test when variances are unequal | Type | Journal Article | ||
| Year | 2001 | Publication | Animal Behaviour. | Abbreviated Journal | Anim. Behav. |
| Volume | 61 | Issue | 6 | Pages | 1247-1249 |
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| ISSN |
0003-3472 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 5048 | ||
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| Author | Tomasello, M.; Call, J | ||||
| Title | Books Received | Type | Journal Article | ||
| Year | 2001 | Publication | Animal Behaviour | Abbreviated Journal | |
| Volume | 61 | Issue | 1 | Pages | 269-270 |
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| Abstract | The Alex Studies: Cognitive and Communicative Abilities of Grey Parrots. By I. M. PEPPERBERG. Cambridge, Massachusetts: Harvard University Press (1999). |
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| ISSN |
0003-3472 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 5446 | ||
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| Author | Gulotta, M.; Gilmanshin, R.; Buscher, T.C.; Callender, R.H.; Dyer, R.B. | ||||
| Title | Core formation in apomyoglobin: probing the upper reaches of the folding energy landscape | Type | Journal Article | ||
| Year | 2001 | Publication | Biochemistry | Abbreviated Journal | Biochemistry |
| Volume | 40 | Issue | 17 | Pages | 5137-5143 |
| Keywords | Animals; Apoproteins/*chemistry; Computer Simulation; Horses; Hydrogen-Ion Concentration; Kinetics; Models, Molecular; Myoglobin/*chemistry; *Protein Folding; Protein Structure, Secondary; Protein Structure, Tertiary; Spectrometry, Fluorescence/instrumentation/methods; Thermodynamics; Tryptophan/chemistry | ||||
| Abstract | An acid-destabilized form of apomyoglobin, the so-called E state, consists of a set of heterogeneous structures that are all characterized by a stable hydrophobic core composed of 30-40 residues at the intersection of the A, G, and H helices of the protein, with little other secondary structure and no other tertiary structure. Relaxation kinetics studies were carried out to characterize the dynamics of core melting and formation in this protein. The unfolding and/or refolding response is induced by a laser-induced temperature jump between the folded and unfolded forms of E, and structural changes are monitored using the infrared amide I' absorbance at 1648-1651 cm(-1) that reports on the formation of solvent-protected, native-like helix in the core and by fluorescence emission changes from apomyoglobin's Trp14, a measure of burial of the indole group of this residue. The fluorescence kinetics data are monoexponential with a relaxation time of 14 micros. However, infrared kinetics data are best fit to a biexponential function with relaxation times of 14 and 59 micros. These relaxation times are very fast, close to the limits placed on folding reactions by diffusion. The 14 micros relaxation time is weakly temperature dependent and thus represents a pathway that is energetically downhill. The appearance of this relaxation time in both the fluorescence and infrared measurements indicates that this folding event proceeds by a concomitant formation of compact secondary and tertiary structures. The 59 micros relaxation time is much more strongly temperature dependent and has no fluorescence counterpart, indicating an activated process with a large energy barrier wherein nonspecific hydrophobic interactions between helix A and the G and H helices cause some helix burial but Trp14 remains solvent exposed. These results are best fit by a multiple-pathway kinetic model when U collapses to form the various folded core structures of E. Thus, the results suggest very robust dynamics for core formation involving multiple folding pathways and provide significant insight into the primary processes of protein folding. | ||||
| Address | Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461, USA | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN |
0006-2960 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:11318635 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 3789 | ||
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| Author | Kimura, R. | ||||
| Title | Volatile substances in feces, urine and urine-marked feces of feral horses | Type | Journal Article | ||
| Year | 2001 | Publication | Canadian Journal of Animal Science | Abbreviated Journal | Can. J. Anim. Sci. |
| Volume | 81 | Issue | 3 | Pages | 411-420 |
| Keywords | Odors (volatile), excrement, scent-marking, masking, horse (feral), (releaser) pheromone | ||||
| Abstract | The identity and amount of volatile substances in the feces, urine and feces scent-marked with urine (i.e., feces mixed with urine) of feral horses was determined by acid/steam distillation and gas chromatography-mass spectrometry. The frequency of excretion and scent marking, as evaluated in the breeding and non-breeding seasons, showed clear evidence of seasonal behavioral differences. The concentration of each substance (fatty acids, alcohols, aldehydes, phenols, amines and alkanes) in the feces differed according to maturity, sex and stage in the reproductive process. They had a characteristic chemical fingerprint. Although the levels of tetradecanoic and hexadecanoic acids in the feces of estrous mares were significantly higher than the respective levels in the feces of non-estrous mares, in the case of scent-marked feces by stallions, the levels of them in the feces from estrous mares had decreased to levels similar to those in non-estrous mares. The concentration of these substances in mares were not significantly different. The presence of a high concentration of cresols in the urine of stallions in the breeding season suggests that one role of scent marking by stallions is masking the odor of the feces produced by mares. | ||||
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| ISSN |
0008-3984 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Equine Museum of Japan, 1-3 Negishidai, Nakaku, Yokohama 231, Japan (hidousch@alles.or.jp) | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 2314 | ||
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| Author | Mouritsen, K.N. | ||||
| Title | Hitch-hiking parasite: a dark horse may be the real rider | Type | Journal Article | ||
| Year | 2001 | Publication | International Journal for Parasitology | Abbreviated Journal | Int J Parasitol |
| Volume | 31 | Issue | 13 | Pages | 1417-1420 |
| Keywords | Animals; *Behavior, Animal; Ecology; Host-Parasite Relations; Snails/*parasitology; Trematoda/growth & development/*physiology; Trematode Infections/transmission | ||||
| Abstract | Many parasites engaged in complex life cycles manipulate their hosts in a way that facilitates transmission between hosts. Recently, a new category of parasites (hitch-hikers) has been identified that seem to exploit the manipulating effort of other parasites with similar life cycle by preferentially infecting hosts already manipulated. Thomas et al. (Evolution 51 (1997) 1316) showed that the digenean trematodes Microphallus papillorobustus (the manipulator) and Maritrema subdolum (the hitch-hiker) were positively associated in field samples of gammarid amphipods (the intermediate host), and that the behaviour of Maritrema subdolum rendered it more likely to infect manipulated amphipods than those uninfected by M. papillorobustus. Here I provide experimental evidence demonstrating that M. subdolum is unlikely to be a hitch-hiker in the mentioned system, whereas the lucky candidate rather is the closely related but little known species, Microphallidae sp. no. 15 (Parassitologia 22 (1980) 1). As opposed to the latter species, Maritrema subdolum does not express the appropriate cercarial behaviour for hitch-hiking. | ||||
| Address | Department of Marine Ecology, Institute of Biological Sciences, University of Aarhus, Finlandsgade 14, DK-8200 Aarhus N, Denmark. kim.mouritsen@stonebow.otago.ac.nz | ||||
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| Language | English | Summary Language | Original Title | ||
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| ISSN |
0020-7519 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:11595227 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 2645 | ||
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| Author | Ferguson, D.L.; Rosales-Ruiz, J. | ||||
| Title | Loading the problem loader: the effects of target training and shaping on trailer-loading behavior of horses | Type | Journal Article | ||
| Year | 2001 | Publication | Journal of Applied Behavior Analysis | Abbreviated Journal | J Appl Behav Anal |
| Volume | 34 | Issue | 4 | Pages | 409-423 |
| Keywords | Animals; *Conditioning, Operant; *Escape Reaction; Female; Horses/*psychology; Reinforcement (Psychology); *Transportation | ||||
| Abstract | The purpose of this study was to develop an effective method for trailer loading horses based on principles of positive reinforcement. Target training and shaping were used to teach trailer-loading behavior to 5 quarter horse mares in a natural setting. All 5 had been trailer loaded before through the use of aversive stimulation. Successive approximations to loading and inappropriate behaviors were the dependent variables. After training a horse to approach a target, the target was moved to various locations inside the trailer. Horses started training on the left side of a two-horse trailer. After a horse was loading on the left side, she was moved to the right side, then to loading half on the right and half on the left. A limited-hold procedure and the presence of a companion horse seemed to facilitate training for 1 horse. Inappropriate behaviors fell to zero immediately after target training, and all the horses successfully completed the shaping sequence. Finally, these effects were observed to generalize to novel conditions (a different trainer and a different trailer). | ||||
| Address | University of North Texas, Denton 76203, USA | ||||
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| Language | English | Summary Language | Original Title | ||
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| ISSN |
0021-8855 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:11800182 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 1915 | ||
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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 | ||||
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| Language | English | Summary Language | Original Title | ||
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| ISSN |
0022-5193 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:11207093 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 555 | ||
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| Author | Johnstone, R.A. | ||||
| Title | Eavesdropping and animal conflict | Type | Journal Article | ||
| Year | 2001 | Publication | Proceedings of the National Academy of Sciences of the United States of America | Abbreviated Journal | Proc. Natl. Acad. Sci. U.S.A. |
| Volume | 98 | Issue | 16 | Pages | 9177-9180 |
| Keywords | *Aggression; Animals; *Behavior, Animal; *Conflict (Psychology); Models, Theoretical | ||||
| Abstract | Fights between pairs of animals frequently take place within a wider social context. The displays exchanged during conflict, and the outcome of an encounter, are often detectable by individuals who are not immediately involved. In at least some species, such bystanders are known to eavesdrop on contests between others, and to modify their behavior toward the contestants in response to the observed interaction. Here, I extend Maynard Smith's well known model of animal aggression, the Hawk-Dove game, to incorporate the possibility of eavesdroppers. I show that some eavesdropping is favored whenever the cost of losing an escalated fight exceeds the value of the contested resource, and that its equilibrium frequency is greatest when costs are relatively high. Eavesdropping reduces the risk of escalated conflict relative to that expected by chance, given the level of aggression in the population. However, it also promotes increased aggression, because it enhances the value of victory. The net result is that escalated conflicts are predicted to occur more frequently when eavesdropping is possible. | ||||
| Address | Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, United Kingdom. raj1003@hermes.cam.ac.uk | ||||
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| Language | English | Summary Language | Original Title | ||
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| ISSN |
0027-8424 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:11459936 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 497 | ||
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