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The effect of water deprivation at 32.2⁰C on the neurosecretory content of the pars nervosa of the white-crowned sparrow, Zonotrichia leucophrys gambeliiVan Devender, Thomas R. January 1969 (has links)
No description available.
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An integrated evaluation of costs and benefits of corticosterone secretion through developmentWada, Haruka, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.
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Natural and Sexual Selection Shape the Acoustic Phenotype of Urban BirdsJanuary 2017 (has links)
acase@tulane.edu / Anthropogenic noise is an evolutionarily recent phenomenon and many animals respond by changing the pitch and timing of their vocalizations to avoid masking. A benefit to modifying a vocal mating signal in the context of noise is increased transmission distance. This same modification may pose a fitness cost if that signal feature is also sexually selected. Bird song is a well-studied sexual signal used in territory defense and mate attraction. Physically difficult to produce components of song are thought to be honest signals of male quality. One such trait is a male's ability to maximize the rate of note production at a given frequency bandwidth; this tradeoff is known as vocal performance. Studies have shown modifications to song in the context of noise, specifically to trill rate and bandwidth. Costs of these modifications may include increased conflict with neighboring males, which could potentially lead to decreased body condition, loss of a territory, or less time spent attracting a female. Few studies have investigated this tradeoff between environmentally induced selection (i.e. natural selection) and social selection (i.e. sexual selection) on song in an urban landscape. Therefore, a gap remains in our knowledge of the consequences on fitness of urban song adaptation for signalers. Using the white-crowned sparrow (Zonotrichia leucophrys) in the San Francisco Bay Area of California, the objectives of my dissertation research include 1) testing if vocal performance is a salient signal for white-crowned sparrows, 2) testing if receivers are responding specifically to variation in trill rate or bandwidth, and 3) testing the effect of ambient noise level on receiver assessment of vocal performance. Overall, my dissertation research suggests that both anthropogenic and natural soundscapes shape the evolution of song and receiver behavior. Modifications to song structure that increase signal detection come at the cost of decreased signal salience for male competitors. Additionally, anthropogenic noise appears to change how males utilize vocal performance. Therefore, species living in noisy areas may face consequences of decreased fitness over time due to masked honest signals and increased male-male conflict. / 1 / Jennifer N. Phillips
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Prolactin and the orientation of Zugunruhe in the white-crowned sparrowDalby, Susan Lynne, 1945- January 1969 (has links)
No description available.
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An integrated evaluation of costs and benefits of corticosterone secretion through developmentWada, Haruka 28 August 2008 (has links)
Not available / text
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An integrated evaluation of costs and benefits of corticosterone secretion through developmentWada, Haruka, 1976- 19 August 2011 (has links)
Not available / text
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Regulation of food intake and body weight in the white-crowned sparrow (Zonotrichia leucophrys gambelii) /Richardson, Ralph D. January 1997 (has links)
Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (leaves [91]-108).
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