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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Variation in female reproductive success in amphibians

Dyal, Leslie A. 08 April 2005 (has links)
My dissertation focuses on the factors that influence variation in female reproductive success in plethodontid salamanders and in toads. Variation in reproductive success fuels evolutionary change. Although, females often have been overlooked in studies of reproductive success due to perceived lower levels of variation when compared to variation in male reproductive success, understanding factors influencing variation in female reproductive success is critical for several reasons. First, female reproduction is usually the limiting factor on population growth. Second, the factors affecting female reproduction provide the impetus for current and evolving patterns of sexual dimorphism. Lastly, male reproductive success inevitably is determined by the reproductive success of the females with which they mate. Recent theoretical developments of sexual conflict have contributed significantly to a renewed emphasis on studies of female reproductive success. Sexual conflict theory elucidates important factors, from the perspective of females, affecting female behavior and reproductive success. Sexual conflict assumes that a female will benefit, in terms of reproductive success and offspring viability, when she is able to freely choose among males, unconstrained by social and environmental factors. Female choice would be constrained if a non-preferred male (i.e., one that would be rejected by a freely choosing female) coerced a female to mate in order to increase his own mating success. The dynamics between discriminating females and non-preferred males will lead to a coevolutionary "arms race", referred to as sexual conflict. From this perspective, secondary male traits may not reflect their intrinsic quality, but rather their ability to manipulate or coerce female mating decisions. The current debate lies in the importance and pervasiveness of sexual conflict. To address the current view of sexual conflict, I investigated whether sexual conflict plays a role in the mating systems of amphibians. In particular, my results support the main assumption that females benefit from freely expressed female mate choice in toads. In addition, I explored the potential influence of sexual conflict in plethodontid salamanders. During mating trials, I documented novel female courtship behaviors. I also examined the effects of male courtship pheromones on female reproductive success to assess the potential role of male pheromones in sexual conflict. My results suggest that sexual conflict also may be an important factor in plethodontid mating systems. My investigations of sexual conflict theory have provided new insights and novel predictions for understanding sexual selection and sexual dimorphism. / Graduation date: 2005
92

Movement behavior, migratory success, and demography of juvenile amphibians in a fragmented landscape

Rothermel, Betsie, January 2003 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
93

Effects of triclosan, triclocarban, and caffeine exposure on the development of amphibian larvae

Palenske, Nicole Marie. Dzialowski, Edward, January 2009 (has links)
Thesis (Ph. D.)--University of North Texas, Aug., 2009. / Title from title page display. Includes bibliographical references.
94

Impacts on terrestrial and streamside herpetofauna by mountaintop removal mining in southern West Virginia

Williams, Jennifer Mravintz. January 2003 (has links)
Thesis (Ph. D.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xi, 153 p. : ill. (some col.), col. maps. Vita. Includes abstract. Includes bibliographical references (p. 136-152).
95

Movement behavior, migratory success, and demography of juvenile amphibians in a fragmented landscape /

Rothermel, Betsie, January 2003 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
96

Using DNA fingerprinting to assess genetic structure of the vernal pool amphibian rana sylvatica

Beatini, Salvatore J. January 2003 (has links)
Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: wood frog; vernal pool conservation; fragmented habitat; Rana sylvatica; DNA fingerprinting. Includes bibliographical references (p. 38-40).
97

Beyond the edge riparian habitat use and forest management effects on stream salamanders in the southern Appalachian mountains /

Crawford, John A., January 2007 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on November 27, 2007) Vita. Includes bibliographical references.
98

The effects of forest practices on a Maine amphibian community /

Patrick, David A., January 2007 (has links) (PDF)
Thesis (Ph.D.) in Wildlife Ecology--University of Maine, 2007. / Includes vita. Includes bibliographical references (leaves 100-117).
99

Amphibian neuropeptides isolation, sequence determination and bioactivity /

Maselli, Vita Marie. January 2006 (has links)
Thesis (Ph.D.)--University of Adelaide, School of Chemistry and Physics, Discipline of Chemistry, 2006. / Includes author's previously published papers. "July 2006" Bibliography: leaves 159-182. Also available in print form.
100

An assessment of the correlation between amphibian populations, chytridiomycete communities, and the ecological integrity of the habitat

DiLeo, Karena V., January 2010 (has links)
Thesis (M.S.)--Rutgers University, 2010. / "Graduate Program in Ecology and Evolution." Includes bibliographical references (p. 55-57).

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