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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.
281

The Aims and Structures of Research Projects That Use Gene Regulatory Information with Evolutionary Genetic Models

January 2017 (has links)
abstract: At the interface of developmental biology and evolutionary biology, the very criteria of scientific knowledge are up for grabs. A central issue is the status of evolutionary genetics models, which some argue cannot coherently be used with complex gene regulatory network (GRN) models to explain the same evolutionary phenomena. Despite those claims, many researchers use evolutionary genetics models jointly with GRN models to study evolutionary phenomena. How do those researchers deploy those two kinds of models so that they are consistent and compatible with each other? To address that question, this dissertation closely examines, dissects, and compares two recent research projects in which researchers jointly use the two kinds of models. To identify, select, reconstruct, describe, and compare those cases, I use methods from the empirical social sciences, such as digital corpus analysis, content analysis, and structured case analysis. From those analyses, I infer three primary conclusions about projects of the kind studied. First, they employ an implicit concept of gene that enables the joint use of both kinds of models. Second, they pursue more epistemic aims besides mechanistic explanation of phenomena. Third, they don’t work to create and export broad synthesized theories. Rather, they focus on phenomena too complex to be understood by a common general theory, they distinguish parts of the phenomena, and they apply models from different theories to the different parts. For such projects, seemingly incompatible models are synthesized largely through mediated representations of complex phenomena. The dissertation closes by proposing how developmental evolution, a field traditionally focused on macroevolution, might fruitfully expand its research agenda to include projects that study microevolution. / Dissertation/Thesis / Doctoral Dissertation Biology 2017
282

Costly Signaling and Prey Choice: the Signaling Value of Hunted Game

January 2019 (has links)
abstract: For most of human history hunting has been the primary economic activity of men. Hunted animals are valued for their food energy and nutrients, however, hunting is associated with a high risk of failure. Additionally, large animals cannot be consumed entirely by the nuclear family, so much of the harvest may be shared to others. This has led some researchers to ask why men hunt large and difficult game. The “costly signaling” and “show-off” hypotheses propose that large prey are hunted because the difficulty of finding and killing them is a reliable costly signal of the phenotypic quality of the hunter. These hypotheses were tested using original interview data from Aché (hunter gatherer; n=52, age range 50-76, 46% female) and Tsimané (horticulturalist; n=40, age range 15-77, 45% female) informants. Ranking tasks and paired comparison tasks were used to determine the association between the costs of killing an animal and its value as a signal of hunter phenotypic quality for attracting mates and allies. Additional tasks compared individual large animals to groups of smaller animals to determine whether assessments of hunters’ phenotypes and preferred status were more impacted by the signal value of the species or by the weight and number of animals killed. Aché informants perceived hunters who killed larger or harder to kill animals as having greater provisioning ability, strength, fighting ability, and disease susceptibility, and preferred them as mates and allies. Tsimané informants held a similar preference for hunters who killed large game, but not for hunters targeting hard to kill species. When total biomass harvested was controlled, both populations considered harvesting more animals in a given time period to be a better signal of preferred phenotypes than killing a single large and impressive species. Male and female informants both preferred hunters who consistently brought back small game over hunters who sometimes killed large animals and sometimes killed nothing. No evidence was found that hunters should forgo overall food return rates in order to signal phenotypic qualities by specializing on large game. Nutrient provisioning rather than costly phenotypic signaling was the strategy preferred by potential mates and allies. / Dissertation/Thesis / Doctoral Dissertation Anthropology 2019
283

Devil in the Details: Systematic Revision of the Devil Crayfish, Lacunicambarus diogenes, Species Complex

Glon, Mael January 2021 (has links)
No description available.
284

Revealing the Structure and Evolution of a Fruit Fly Gene Regulatory Network by Varied Genetic Approaches

Hughes, Jesse T. January 2021 (has links)
No description available.
285

The Unknown and the Unnamed

Lyon, Calista 30 September 2019 (has links)
No description available.
286

What's In A Neanderthal: A Comparative Analysis

Stephan, Taylorlyn January 2017 (has links)
No description available.
287

Phylogeographic analysis of the prairie vole (Microtus ochrogaster)

Robinson, Joshua J. 27 July 2020 (has links)
No description available.
288

Evaluating <i>in silico</i> enhancer prediction for non-traditional model organisms through a cross species reporter assay

Tieke, Ellen Claire 19 April 2023 (has links)
No description available.
289

The Skeletal Biology of Hibernating Woodchucks (<i>Marmota monax</i>)

Doherty, Alison H. 28 March 2013 (has links)
No description available.
290

Ontogeny of the Brain Endocasts of Ostriches (Aves: Struthio camelus) with Implications for Interpreting Extinct Dinosaur Endocasts

Romick, Cheyenne Ariel January 2013 (has links)
No description available.

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