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Behavior and Ethology Commons

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Full-Text Articles in Behavior and Ethology

Cognitive Representation In Transitive Inference: A Comparison Of Four Corvid Species, Alan B. Bond, Cynthia A. Wei, Alan C. Kamil Jan 2010

Cognitive Representation In Transitive Inference: A Comparison Of Four Corvid Species, Alan B. Bond, Cynthia A. Wei, Alan C. Kamil

Alan Bond Publications

During operant transitive inference experiments, subjects are trained on adjacent stimulus pairs in an implicit linear hierarchy in which responses to higher ranked stimuli are rewarded. Two contrasting forms of cognitive representation are often used to explain resulting choice behavior. Associative representation is based on memory for the reward history of each stimulus. Relational representation depends on memory for the context in which stimuli have been presented. Natural history characteristics that require accurate configural memory, such as social complexity or reliance on cached food, should tend to promote greater use of relational representation. To test this hypothesis, four corvid species …


How Birds Combat Ectoparasites, Dale H. Clayton, Jennifer A. H. Koop, Christopher W. Harbison, Brett R. Moyer, Sarah E. Bush Jan 2010

How Birds Combat Ectoparasites, Dale H. Clayton, Jennifer A. H. Koop, Christopher W. Harbison, Brett R. Moyer, Sarah E. Bush

Harold W. Manter Laboratory: Library Materials

Birds are plagued by an impressive diversity of ectoparasites, ranging from feather-feeding lice, to feather-degrading bacteria. Many of these ectoparasites have severe negative effects on host fitness. It is therefore not surprising that selection on birds has favored a variety of possible adaptations for dealing with ectoparasites. The functional significance of some of these defenses has been well documented. Others have barely been studied, much less tested rigorously. In this article we review the evidence--or lack thereof--for many of the purported mechanisms birds have for dealing with ectoparasites. We concentrate on features of the plumage and its components, as well …