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Synthesizing Phylogeography And Community Ecology To Understand Patterns Of Community Diversity, Trevor J. Williams

Theses and Dissertations

Community ecology is the study of the patterns and processes governing species abundance, distribution, and diversity within and between communities. Likewise, phylogeography is the study of the historic processes controlling genetic diversity across space. Both fields investigate diversity, albeit at different temporal, spatial and taxonomic scales and therefore have varying assumptions. Community ecology typically focuses on contemporary mechanisms whereas phylogeography studies historic ones. However, new research has discovered that both genetic and community diversity can be influenced by contemporary and historic processes in tandem. As such, a growing number of researchers have called for greater integration of phylogeography and ecology …

Does Negative Frequency-Dependent Selection Maintain Gonopodial Asymmetry In Xenophallus Umbratilis?, Mary-Elise Johnson, Erik S. Johnson, Jerald B. Johnson

Library/Life Sciences Undergraduate Poster Competition 2020

How does negative frequency-dependent selection emerge in populations?

The idea of negative frequency-dependent selection is elegant and simple: Traits are evolutionarily favored when they are rare but disfavored when they become common. This can theoretically lead to oscillations in the ratios of morphs within populations. Unfortunately, there is still little evidence that this process occurs in the wild. The live bearing fish Xenophallus umbratilis exhibits uniquely asymetrical morphology in the male mating structure, called a gonopodium. In this species, the gonopodium terminates with either a dextral (right-handed) or sinistral (left handed) twist, suggesting that mating within this species could be …

Bacterial Community Ecology Of The Colon In Mus Musculus, Rachel Marie Nettles

Theses and Dissertations

The gut microbiome is a community of closely interacting microbes living in the gastrointestinal tract. Its structure has direct relevance to health. Disturbances to the microbiome, such as due to antibiotic use, have been implicated in various diseases. The goal of this study was to determine how the gut microbiome reacts to and recovers from disturbance caused by antibiotics. Because diet also influences the microbiome, this study included the interaction between diet and antibiotics. Half of the mice in each diet treatment were given antibiotics to disturb their microbiomes. After cessation of antibiotics, mice were paired in combinations within diets …