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The Evolution And Reproductive Ecology Of Oenothera (Onagraceae), Kyra Krakos
The Evolution And Reproductive Ecology Of Oenothera (Onagraceae), Kyra Krakos
All Theses and Dissertations (ETDs)
This dissertation describes the role of pollination in the floral diversification of Oenothera with an integration of both ecological and phylogenetic approaches. Oenothera: Onagraceae) is a model system for studying plant reproductive biology. It provides excellent examples of shifts in reproductive traits such as pollination and breeding system, features that have been important in angiosperm diversification. These systems are evolutionarily labile; they easily shift between different states. These different reproductive traits may shift in a concerted fashion; therefore, a more comprehensive approach to understanding the evolution of these plant systems simultaneously addresses shifts in pollination and breeding system. Using 54 …
Effects Of The Aquatic To Terrestrial Habitat Ratio On An Amphibian Predator And Its Prey, Amber Kramer
Effects Of The Aquatic To Terrestrial Habitat Ratio On An Amphibian Predator And Its Prey, Amber Kramer
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This dissertation explores the effects of varying the composition of aquatic and terrestrial habitats in a landscape: the aquatic to terrestrial ratio) on amphibians that use both the aquatic and terrestrial habitats during their lives. In Chapter 1, I first used meta-analysis and simulations to demonstrate that as the longevity of an amphibian increases, the elasticity of the population growth rate to perturbations in the aquatic: larval) habitat decreases. In Chapter 2, I examined the abundance of larvae of a long-lived amphibian, Ambystoma maculatum, across landscapes that varied in their aquatic to terrestrial ratios and found that larvae of this …
Dietary Shifts, Niche Relationships And Interspecific Competition In Sympatric Grey Langur (Semnopithecus Entellus) And Purple-Faced Langur (Trachypithecus Vetulus) In Sri Lanka, Rajnish Vandercone
Dietary Shifts, Niche Relationships And Interspecific Competition In Sympatric Grey Langur (Semnopithecus Entellus) And Purple-Faced Langur (Trachypithecus Vetulus) In Sri Lanka, Rajnish Vandercone
All Theses and Dissertations (ETDs)
Understanding how niche differences evolve in ecologically similar species and how these differences are maintained ecologically is a fundamental question in ecology. Interspecific competition has been shown to influence the behavior and ecology of organisms in a wide range of ecological communities. However, the broader role of interspecific competition in primate communities is unclear as relatively few studies have explored this question. This is especially true for folivorous primate communities, such as those of colobine monkeys, in which the influence of interspecific competition on aspects of the ecology of these monkeys is yet to be determined. In this dissertation, I …
Causes Of Rarity In Glade-Endemic Plants: Implications For Responses To Climate Change, Nicole Miller-Struttmann
Causes Of Rarity In Glade-Endemic Plants: Implications For Responses To Climate Change, Nicole Miller-Struttmann
All Theses and Dissertations (ETDs)
This dissertation documents the relationship between stress-adaptation and reproductive specialization in three endemic plant species: Delphinium treleasei, Echinacea paradoxa, and Scutellaria bushii) that are locally abundant but restricted to stressful habitats and their closely-related congeners: D. carolinianum, E. pallida, S. ovata, and S. parvula) that have broader habitat use, including hot, xeric habitats. In Chapter Two, I test two hypotheses concerning reproductive specialization in endemic plants and their common congeners: CC). I quantify morphological traits that are associated with stress-adaptation and reproductive specialization, pollinator behavior, and reproductive specialization. The locally abundant, habitat specialist: LAHS) species were significantly different from their …