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Full-Text Articles in Ecology and Evolutionary Biology

Rodent Dental Microwear Texture Analysis As A Proxy For Fine-Scale Paleoenvironment Reconstruction, Jenny H. E. Burgman May 2022

Rodent Dental Microwear Texture Analysis As A Proxy For Fine-Scale Paleoenvironment Reconstruction, Jenny H. E. Burgman

Graduate Theses and Dissertations

Dental microwear texture analysis (DMTA) of fossil fauna has become a valuable tool for dietary inference and paleoenvironment reconstruction. Most of this work has utilized larger taxa with larger home ranges. These studies may result in broader-scale habitat inferences that could mask the details of complex mosaic habitats. Rodent DMTA offers an opportunity to work at finer spatial scales because most species have smaller home ranges. Rodents are also keystone species within their ecosystems, abundant, ubiquitous, and found in many fossil deposits. These attributes make them excellent proxies for environmental reconstructions. However, the application of DMTA to rodents remains relatively …


Phylogeny And Evolutionary Genomics Of Non-Photosynthetic Diatoms, Anastasiia Onyshchenko May 2018

Phylogeny And Evolutionary Genomics Of Non-Photosynthetic Diatoms, Anastasiia Onyshchenko

Graduate Theses and Dissertations

Diatoms are prolific photosynthesizers responsible for some 20% of global primary production. In real terms, the oxygen in one of every five breaths traces back to photosynthesis by marine diatoms. Among the tens of thousands of diatom species, a small handful of colorless diatom species in the genus Nitzschia have lost photosynthesis altogether and rely exclusively on extracellular organic carbon for growth. I used DNA sequence data to reconstruct the phylogeny of this group, and found that nonphotosynthetic diatoms are monophyletic, indicating that photosynthesis was lost just one time over the course of some 200 million years of diatom evolution. …


Fishes As A Template For Reticulate Evolution: A Case Study Involving Catostomus In The Colorado River Basin Of Western North America, Max Russell Bangs Dec 2016

Fishes As A Template For Reticulate Evolution: A Case Study Involving Catostomus In The Colorado River Basin Of Western North America, Max Russell Bangs

Graduate Theses and Dissertations

Hybridization is neither simplistic nor phylogenetically constrained, and post hoc introgression can have profound evolutionary effects. Most studies have focused on tractable model systems, rather than organisms with complicated phylogenetic histories. Finescale Sucker (genus Catostomus) in western North America is recognized as a paradigm of fish hybridization. Yet, its extent of historic and contemporary introgression is largely unstudied, an aspect that impedes the resolution of its phylogeny as a baseline for conservation. To explore reticulation in this group, I assayed variation of 20 Catostomus species across temporal and geographic scales by analyzing hundreds of samples and employing a combination of …


Transcriptomic Insights Into The Diplontic Life History Of Diatoms, Colton Richard Kessenich May 2014

Transcriptomic Insights Into The Diplontic Life History Of Diatoms, Colton Richard Kessenich

Graduate Theses and Dissertations

An organism's life cycle is the direct result of its evolutionary history and represents a fundamental aspect of its ancestry and ecology. Yet the process of linking alternating life-history stages has proven to be challenging, if not impossible in some cases. Diatoms (Bacillariophyceae) are no exception to this challenge, and their diversity of life stages and reproductive strategies add further challenges. A central focus of diatom research has been to unravel the evolutionary events that led to their extraordinary diversity, a line of inquiry that has been greatly aided by the availability of next-generation sequence data. Yet without proper taxonomic …