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Author | Peters, G.; Tembrock, G. | ||||
Title | Subharmonics, biphonation, and deterministic chaos in mammal vocalizations | Type | Journal Article | ||
Year | 1998 | Publication | Bioacoustics | Abbreviated Journal | |
Volume | 9 | Issue | Pages | ||
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Call Number | Equine Behaviour @ team @ Peters1998 | Serial | 6483 | ||
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Author | Cameron, E.Z. | ||||
Title | Is suckling behaviour a useful predictor of milk intake? A review | Type | Journal Article | ||
Year | 1998 | Publication | Animal Behaviour. | Abbreviated Journal | Anim. Behav. |
Volume | 56 | Issue | 3 | Pages | 521-532 |
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Abstract | In studies on mammalian parental investment, time spent suckling is often used as a predictor of the milk transferred from mother to infant. It is assumed that the rate of milk transfer is positively correlated with the time spent suckling. However, this assumption has not been tested and empirical studies show conflicting results. Nevertheless, in species in which suckling can readily be observed, time spent suckling is still used to measure milk transfer, although an increasing number of workers recognize that the measure is potentially inaccurate. A meta-analysis on studies that have correlated measures of time spent suckling with milk intake estimates based on weight gain revealed a weak positive relationship and significant heterogeneity between studies. Isotope-labelling techniques for the measurement of milk transfer independent of behaviour have been in use since the 1970s, particularly in studies of species in which suckling is difficult to observe. Only one study has attempted to correlate behavioural measures with independent isotope measures, and it found no relationship between the two measures. I suggest that researchers have avoided such a test as it is unlikely that a strong relationship will be found between milk transfer and suckling behaviour, and I discuss the various factors that confound the relationship and contribute to high heterogeneity between studies. Consequently, the assumption that milk transfer can be measured by time spent suckling has inadequate empirical foundation, and needs to be tested using isotope-labelling methods. Copyright 1998 The Association for the Study of Animal Behaviour | ||||
Address | Department of Ecology, Massey University | ||||
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Language | English | Summary Language | Original Title | ||
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ISSN | 0003-3472 | ISBN | Medium | ||
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Notes | PMID:9784199 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 419 | ||
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Author | de VRIES, H.A.N. | ||||
Title | Finding a dominance order most consistent with a linear hierarchy: a new procedure and review | Type | Journal Article | ||
Year | 1998 | Publication | Animal Behaviour. | Abbreviated Journal | Anim. Behav. |
Volume | 55 | Issue | 4 | Pages | 827-843 |
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Abstract | A procedure for ordering a set of individuals into a linear or near-linear dominance hierarchy is presented. Two criteria are used in a prioritized way in reorganizing the dominance matrix to find an order that is most consistent with a linear hierarchy: first, minimization of the numbers of inconsistencies and, second, minimization of the total strength of the inconsistencies. The linear ordering procedure, which involves an iterative algorithm based on a generalized swapping rule, is feasible for matrices of up to 80 individuals. The procedure can be applied to any dominance matrix, since it does not make any assumptions about the form of the probabilities of winning and losing. The only assumption is the existence of a linear or near-linear hierarchy which can be verified by means of a linearity test. A review of existing ranking methods is presented and these are compared with the proposed method. | ||||
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Call Number | refbase @ user @ | Serial | 457 | ||
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Author | Lachmann M.; Bergstrom C.T. | ||||
Title | Signalling among Relatives II. Beyond the Tower of Babel | Type | Journal Article | ||
Year | 1998 | Publication | Theoretical Population Biology | Abbreviated Journal | Theor. Pop. Biol. |
Volume | 54 | Issue | 2 | Pages | 146-160 |
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Abstract | Models of costly signalling are commonly employed in evolutionary biology in order to explain how honest communication between individuals with conflicting interests can be stable. These models have focused primarily on a single type of honest signalling equilibrium, the separating equilibrium in which any two different signallers send distinct signals, thereby providing signal receivers with complete information. In this paper, we demonstrate that in signalling among relatives (modelled using the Sir Philip Sidney game), there is not one but a large number of possible signalling equilibria, most of which are pooling equilibria in which different types of signallers may share a common signal. We prove that in a general Sir Philip Sidney game, any partition of signallers into equi-signalling classes can have a stable signalling equilibrium if and only if it is a contiguous partition, and provide examples of such partitions. A similar (but slightly stricter) condition is shown to hold when signals are transmitted through a medium with signalling error. These results suggest a solution to a problem faced by previous signalling theory models: when we consider the separating equilibrium, signal cost is independent of the frequency of individuals sending that signal and, consequently, even very rare signaller types can drastically affect signal cost. Here, we show that by allowing these rare signallers to pool with more common signallers, signal cost can be greatly reduced. Copyright 1998 Academic Press. | ||||
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Call Number | refbase @ user @ | Serial | 560 | ||
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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 | ||||
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ISSN | 0027-8424 | ISBN | Medium | ||
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Notes | PMID:9560235 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 561 | ||
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Author | Templeton, J.J. | ||||
Title | Learning from others' mistakes: a paradox revisited | Type | Journal Article | ||
Year | 1998 | Publication | Animal Behaviour. | Abbreviated Journal | Anim. Behav. |
Volume | 55 | Issue | 1 | Pages | 79-85 |
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Abstract | Some researchers have reported the paradoxical finding of enhanced social learning when naive observers learn from unskilled rather than skilled demonstrators, particularly in discrimination tasks. In two experiments with starlings,Sturnus vulgaris, I considered whether this enhanced learning is because the observer (1) sees incorrect responses only, (2) sees both correct and incorrect responses or (3) sees an increase in the proportion of correct responses over trials. In experiment 1, individual starlings observed a demonstrator bird perform multiple simultaneous discrimination tasks. In one group, the demonstrator always picked the correct stimulus; in another group, the demonstrator always picked the incorrect stimulus; in a third group, the demonstrator consistently picked the correct stimulus 50% of the time. Those subjects that observed only incorrect choices performed significantly better than the other two groups, but none of the birds achieved the 90% correct performance criterion. Experiment 2 involved a single discrimination task; thus, a fourth group was added to control for individual learning. Again, subjects that observed only incorrect responses learned the discrimination significantly more quickly than the other three groups. Subjects that observed the demonstrator make both correct and incorrect responses were equally likely to select the same (correct) or opposite (incorrect) stimulus when the demonstrator picked the correct stimulus. When the demonstrator picked the incorrect stimulus, however, these subjects were significantly more likely to pick the opposite (correct) stimulus. These findings suggest that when learning a discrimination problem, observing a foraging companion's lack of success is more informative than observing its success. | ||||
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Call Number | refbase @ user @ | Serial | 567 | ||
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Author | Tomasello, M.; Call, J.; Hare, B. | ||||
Title | Five primate species follow the visual gaze of conspecifics | Type | Journal Article | ||
Year | 1998 | Publication | Animal Behaviour. | Abbreviated Journal | Anim. Behav. |
Volume | 55 | Issue | 4 | Pages | 1063-1069 |
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Abstract | Individuals from five primate species were tested experimentally for their ability to follow the visual gaze of conspecifics to an outside object. Subjects were from captive social groups of chimpanzees,Pan troglodytes, sooty mangabeys,Cercocebus atys torquatus, rhesus macaques,Macaca mulatta, stumptail macaques,M. arctoides, and pigtail macaques,M. nemestrina. Experimental trials consisted of an experimenter inducing one individual to look at food being displayed, and then observing the reaction of another individual (the subject) that was looking at that individual (not the food). Control trials consisted of an experimenter displaying the food in an identical manner when the subject was alone. Individuals from all species reliably followed the gaze of conspecifics, looking to the food about 80% of the time in experimental trials, compared with about 20% of the time in control trials. Results are discussed in terms of both the proximate mechanisms that might be involved and the adaptive functions that might be served by gaze-following. | ||||
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Notes | Approved | no | |||
Call Number | refbase @ user @ | Serial | 592 | ||
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Author | Brannon, E.M.; Terrace, H.S. | ||||
Title | Ordering of the numerosities 1 to 9 by monkeys | Type | Journal Article | ||
Year | 1998 | Publication | Science (New York, N.Y.) | Abbreviated Journal | Science |
Volume | 282 | Issue | 5389 | Pages | 746-749 |
Keywords | Animals; *Discrimination (Psychology); Macaca mulatta/*psychology; *Mathematics; *Mental Processes | ||||
Abstract | A fundamental question in cognitive science is whether animals can represent numerosity (a property of a stimulus that is defined by the number of discriminable elements it contains) and use numerical representations computationally. Here, it was shown that rhesus monkeys represent the numerosity of visual stimuli and detect their ordinal disparity. Two monkeys were first trained to respond to exemplars of the numerosities 1 to 4 in an ascending numerical order (1 --> 2 --> 3 --> 4). As a control for non-numerical cues, exemplars were varied with respect to size, shape, and color. The monkeys were later tested, without reward, on their ability to order stimulus pairs composed of the novel numerosities 5 to 9. Both monkeys responded in an ascending order to the novel numerosities. These results show that rhesus monkeys represent the numerosities 1 to 9 on an ordinal scale. | ||||
Address | Department of Psychology, Columbia University, New York, NY 10027, USA. liz@psych.columbia.edu | ||||
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ISSN | 0036-8075 | ISBN | Medium | ||
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Notes | PMID:9784133 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 606 | ||
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Author | Schnall, Simone; Gattis,Merideth | ||||
Title | Transitive Inference by Visual Reasoning | Type | Conference Volume | ||
Year | 1998 | Publication | Proceedings of the Twentieth Annual Conference of the Cognitive Science Society | Abbreviated Journal | |
Volume | Issue | Pages | 929-934 | ||
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Abstract | Two experiments are reported that investigated the influence of linear spatial organization on transitive inference performance. Reward/no-reward relations between overlapping pairs of elements were presented in a context of linear spatial order or random spatial order. Participants in the linear arrangement condition showed evidence for visual reasoning: They systematically mapped spatial relations to conceptual relation and used the spatial relations to make inferences on a reasoning task in a new spatial context. We suggest that linear ordering may be a “good figure”, by constituting a parsimonious representation for the integration of premises, as well as for the inferencing process. The late emergence of transitive inference in children may be the result of limited cognitive capacity, which --unless an external spatial array is available --constrains the construction of an internal spatial array. |
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Call Number | refbase @ user @ | Serial | 610 | ||
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Author | Schooening, B. | ||||
Title | Ethology of the horse | Type | Journal Article | ||
Year | 1998 | Publication | Praktische Tierarzt | Abbreviated Journal | Prakt. Tierarzt |
Volume | 79 | Issue | 6 Suppl. | Pages | 25-28 |
Keywords | Dominance; Ethology; Horse; Propedeutics | ||||
Abstract | The paper starts with a short introduction/definition about ethology and the used methods in this scientific field, giving special examples for horses and about how their “normal behaviour” is measured. The behaviour repertoire of horses is described in a brief outline with special emphasis on their social systems and hierarchies and the problem of dominance, especially in interaction with humans. Schlütersche GmbH & Co. KG, Verlag und Druckerei. | ||||
Address | Saselbergweg 32, 22395 Hamburg, Germany | ||||
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ISSN | 0032681x (Issn) | ISBN | Medium | ||
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Notes | Cited By (since 1996): 1; Export Date: 21 April 2007; Source: Scopus; Language of Original Document: German; Correspondence Address: Schoßning, B.Saselbergweg 32 22395 Hamburg, Germany; email: Dr.B.Schoening@t-online.de | Approved | no | ||
Call Number | refbase @ user @ | Serial | 789 | ||
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