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Geographic Variation In Alarm Calls Of Gunnison's Prairie Dogs, C. N. Slobodchikoff, S. H. Ackers, M. Van Ert Dec 1998

Geographic Variation In Alarm Calls Of Gunnison's Prairie Dogs, C. N. Slobodchikoff, S. H. Ackers, M. Van Ert

Communication Skills Collection

Geographic variation in alarm calls of Gunnison's prairie dogs (Cynomys gunnisoni) was analyzed at regional and local scales. Alarm calls in response to a common stimulus (the same human) were recorded at four colonies near Flagstaff, Arizona, and at six sites throughout the southwestern United States. The acoustic structure of calls was analyzed for seven call variables. Regional differences fit the prediction of greater differences with increased geographical separation. Differences between colonies at a local scale were not related to geographical distance, suggesting that local dialects exist within a region. Differences in the level of predation by humans …


Evolution And Animal Welfare, Marian Stamp Dawkins Sep 1998

Evolution And Animal Welfare, Marian Stamp Dawkins

Assessment of Animal Welfare Collection

Animal welfare is a topic often thought to reside outside mainstream biology. The complexity of the methods used to assess welfare (such as health, physiology, immunological state, and behavior) require an understanding of a wide range of biological phenomena. Furthermore, the "welfare" of an animal provides a framework in which a diversity of its responses can be understood as fitness-enhancing mechanisms. Different methods for assessing animal welfare are discussed, with particular emphasis on the role of an animal's own choices and reinforcement mechanisms. No part of biology is as yet able to explain consciousness, but by confronting the possibility that …


Fmri Of Monkey Visual Cortex, Lisa Stefanacci, Paul Reber, Jennifer Costanza, Eric Wong, Richard Buxton, Stuart Zola, Larry R. Squire, Thomas D. Albright Jun 1998

Fmri Of Monkey Visual Cortex, Lisa Stefanacci, Paul Reber, Jennifer Costanza, Eric Wong, Richard Buxton, Stuart Zola, Larry R. Squire, Thomas D. Albright

Neurology Collection

While functional magnetic resonance imaging (fMRI) is now used widely for demonstrating neural activity-related signals associated with perceptual, motor, and cognitive processes in humans, to date this technique has not been developed for use with nonhuman primates. fMRI in monkeys offers a potentially valuable experimental approach for investigating brain function, which will complement and aid existing techniques such as electrophysiology and the behavioral analysis of the effects of brain lesions. There are, however, a number of significant technical challenges involved in using fMRI with monkeys. Here, we describe the procedures by which we have overcome these challenges to …


A Comparison Of Encephalization Between Odontocete Cetaceans And Anthropoid Primates, L. Marino Apr 1998

A Comparison Of Encephalization Between Odontocete Cetaceans And Anthropoid Primates, L. Marino

Veterinary Science and Medicine Collection

There have been very few studies of brain size and encephalization in cetaceans and essentially none that have made direct quantitative comparisons of cetaceans and another mammalian group using large normative samples. In the present study two different measures of encephalization were calculated and used to rank and compare 21 odontocete species and 60 anthropoid primate species. Comparisons were made both within and between the two groups. Results show that the encephalization level of Homo sapiens is still extraordinary relative to that of nonhuman species. Nevertheless, a subset of delphinid odontocetes are significantly more highly encephalized than the most highly …


‘Pleasures’, ‘Pains’ And Animal Welfare: Toward A Natural History Of Affect, D. Fraser, I. J.H. Duncan Jan 1998

‘Pleasures’, ‘Pains’ And Animal Welfare: Toward A Natural History Of Affect, D. Fraser, I. J.H. Duncan

Animal Welfare Collection

In hedonic theories of motivation, 'motivational affective states' (MASs) are typically seen as adaptations which motivate certain types of behaviour, especially in situations where a flexible or learned response is more adaptive than a rigid or reflexive one. MASs can be negative (eg unpleasant feelings of hunger or pain) or positive (eg pleasant feelings associated with eating and playing). Hedonic theories often portray negative and positive MASs as opposite ends of a one-dimensional scale.

We suggest that natural selection has favoured negative and positive affect as separate processes to solve two different types of motivational problems. We propose that negative …