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Full-Text Articles in Life Sciences

Biogeography And Conservation Of Tidal Marsh Bird Communities Across A Changing Landscape, Maureen D. Correll Dec 2015

Biogeography And Conservation Of Tidal Marsh Bird Communities Across A Changing Landscape, Maureen D. Correll

Electronic Theses and Dissertations

Given the current mass extinction crisis and continued fragmentation of resources worldwide, the outlook is dire for global biodiversity. Rising global temperature, sea levels, and storm frequency all create environmental conditions that can drive change in species abundance and distribution across a landscape. Those species reliant upon a single type of habitat and resource for survival, termed “specialists”, are particularly vulnerable to change due to their inability to utilize a variety of resources well. As a result, specialism is now considered one of the dominant factors determining extinction of species. In this dissertation I explore the effects of disturbance on …


A New Adaptive Landscape: Urbanization As A Strong Evolutionary Force, Lauren Christie Breza Dec 2015

A New Adaptive Landscape: Urbanization As A Strong Evolutionary Force, Lauren Christie Breza

Masters Theses

Urbanization is rapidly increasing as human population growth steadily grows, but there is little consensus of the ecological consequence of this population shift and almost no information of the evolutionary consequences for local biodiversity. Nearly two-thirds of the world’s population will live in city centers by 2050 with profound impacts on landscapes that can act as important agents of selection. This study aims to identify 1) the net effect of urbanization on species richness, 2) how phylogenetic diversity varies between urban and rural sites, and 3) the strength of urbanization as a selection pressure. First, a meta-analysis was conducted in …


Conservation Planning In A Changing World, Austin Walker Milt Aug 2015

Conservation Planning In A Changing World, Austin Walker Milt

Doctoral Dissertations

As a science and practice dedicated to preventing, stopping, and reversing negative effects on nature, conservation is constantly faced with new challenges. Combine this fact with the rise of large, freely available datasets and computational power, and the result is a need to advance the methods and conceptual approach to conservation planning. In my dissertation I present novel methods and address research questions that aim to keep conservation science and practice relevant and effective in a changing world. This picture of continual change is illustrated in Chapter 1, in which I explore how the ongoing collection of observations of rare …


Systematics Of The African River Frog Genus Amietia (Anura: Pyxicephalidae) From Eastern Democratic Republic Of The Congo, Thornton Robert Larson Jan 2015

Systematics Of The African River Frog Genus Amietia (Anura: Pyxicephalidae) From Eastern Democratic Republic Of The Congo, Thornton Robert Larson

Open Access Theses & Dissertations

The African river frog genus Amietia is found near rivers and other lentic water sources throughout central, eastern and southern Africa. Because the genus includes multiple morphologically conservative species, taxonomic studies of river frogs have been limited. We sampled 49 individuals of Amietia from multiple localities in and near the Albertine Rift (AR) of Burundi, Democratic Republic of the Congo and Uganda. We utilized single-gene (16S) and concatenated (12S, 16S, cytochrome b and RAG1) gene-tree analyses and coalescent species-tree analyses to construct phylogenetic trees. Two divergence dating approaches were used in BEAST, including secondary calibration points with 12S, 16S and …


Emergent Non-Consumptive Predator Effects Alter Habitat Colonization By Dipteran Prey, Ethan G. Staats Jan 2015

Emergent Non-Consumptive Predator Effects Alter Habitat Colonization By Dipteran Prey, Ethan G. Staats

Theses and Dissertations

When ovipositing, prey organisms avoid habitat patches containing predator cues because predators consume, and negatively affect the fitness of their prey. Richness of predator species often enhances the strength of consumptive predator effects, but little is known about how multiple predators combined affect prey non-consumptively. We quantified dipteran colonization in aquatic mesocosms in response to varied predator richness. Multiple predator species combined reduced oviposition by Culex mosquitoes, chironomid midges, and the general colonizing dipteran community more than predicted by the effects of the independent predator species. Previous research which quantifies effects of multiple predators on prey as prey abundance, but …