Life Sciences Commons^™

Riparian Ecosystem Response To Hemlock Woolly Adelgid (Adelges Tsugae) Induced Eastern Hemlock (Tsuga Canadensis) Mortality In The Great Smoky Mountains National Park, Usa, Misty Dawn Huddleston

Doctoral Dissertations

An invasive insect, hemlock woolly adelgid (HWA), has initiated widespread hemlock decline and mortality in the Great Smoky Mountains National Park (GSMNP). Riparian hemlock mortality impacts on vegetative and aquatic systems of first-order, headwater streams were evaluated. Reference sites for this study were representative of the best available conditions within the GSMNP, with initial stages of HWA presence. Impacted sites were defined as areas with over 90 percent hemlock mortality. Impacted streams had decreased canopy coverage and increased light availability. Residual red maple, yellow birch, and sweet birch capitalized on the loss of hemlock, with increases in relative basal area …

Multiple Responses By Cerulean Warblers To Experimental Forest Disturbance In The Appalachian Mountains, Than James Boves

Doctoral Dissertations

The Cerulean Warbler (Setophaga cerulea) is a mature forest obligate and one of the fastest declining songbird species in the United States. This decline may be related to a lack of disturbance within contemporary forests; however, the consequences of disturbance on the species have not been rigorously evaluated. Thus, we assessed multiple responses by Cerulean Warblers to a range of experimental forest disturbances across the core of their breeding range in the Appalachian Mountains. We quantified individual and population responses to these manipulations, and assessed the potential consequences of disturbance on the sexual signaling system. Male ceruleans were …

An Evaluation Of Population Estimators And Forage Availability And Nutritional Quality For White-Tailed Deer In Tennessee, Jared Tyler Beaver

Masters Theses

Given the white-tailed deer’s (Odocoileus virginianus; deer) popularity and potentially negative impact on forested systems; Arnold Air Force Base (AAFB) in Tullahoma, Tennessee, USA has made minimizing negative deer impacts on biodiversity a priority. To address these management issues, I initiated a study on AAFB to investigate deer survey techniques and the effects of deer density on forage availability across vegetative communities.

Current use of infrared-triggered cameras (camera) for estimating deer populations does not provide a measure of precision critical for density estimation. I conducted a camera survey for deer in Wildlife Management Area (WMA) Units 1 and …

Plant Genotype, Not Nutrients, Shape Aphid Population Dynamics, Heather E. Tran, Lara Souza, Nathan J. Sanders, Aimee T. Classen

Chancellor’s Honors Program Projects

No abstract provided.

Factors Related To Nest Survival And Over-Winter Survival Of A Northern Bobwhite (Colinus Virginianus) Population In Southwest Florida, Steven Kenneth Brinkley

Masters Theses

The northern bobwhite (Colinus virginianus) is a gallinaceous upland game bird dependent on early successional grassland habitat for reproduction and survival. Bobwhite populations have been declining range-wide for nearly a half century. The habitat of Babcock-Webb Wildlife Management Area (BWWMA) in southwest Florida is mostly virgin, early successional grassland and pine flatwoods. Although BWWMA is located in the far southern end of the bobwhite range, the area is a popular public land for bobwhite hunting. The BWWMA bobwhite population has declined evidenced by a dramatic decrease in harvest over the last 20 years. The two objectives of my …

Consequences Of Gene Flow And Transgene Introgression In Hybrids Between Transgenic Brassica Napus And Its Weedy Wild Relative Brassica Rapa, Reginald Jason Millwood

Masters Theses

The adventitious presence of transgenes and their potential impact on the environment has been a topic of concern for many years. To address these concerns the following chapters discuss past and current research of gene flow and introgression, methods for transgene detection and monitoring, and the results from field-level experiments using artificially introgressed advanced generation hybrids. The field studies were designed to be a worst-case scenario where hybrids were produced by hand-crossing transgenic Brassica napus (AACC, 2n = 38) and its weedy wild relative Brassica rapa (AA, 2n = 20). B. napus was transgenic for the green fluorescent protein [m-GFP-5 …

Evolution, Speciation, And Conservation Of Amblyopsid Cavefishes, Matthew Lance Niemiller

Doctoral Dissertations

Cave organisms are classic examples of regressive evolution, as many disparate taxa have evolved similar convergent phenotypes in subterranean environments. While recent phylogeographic and population genetic analyses have greatly improved our understanding of the evolutionary and biogeographic history of cave organisms, many questions remain unanswered or poorly investigated. I investigated several evolutionary and biogeographic questions in a model system for regressive evolution and studies of ecological and evolutionary mechanisms, amblyopsid cavefishes. In chapter I, I used recently developed methods to delimit species boundaries and relationships in a widely distributed cavefish, Typhlichthys. I show that species diversity in Typhlichthys is …

Optimal Theory Applied In Integrodifference Equation Models And In A Cholera Differential Equation Model, Peng Zhong

Doctoral Dissertations

Integrodifference equations are discrete in time and continuous in space, and are used to model the spread of populations that are growing in discrete generations, or at discrete times, and dispersing spatially. We investigate optimal harvesting strategies, in order to maximize the profit and minimize the cost of harvesting. Theoretical results on the existence, uniqueness and characterization, as well as numerical results of optimized harvesting rates are obtained. The order of how the three events, growth, dispersal and harvesting, are arranged also affects the harvesting behavior.

Cholera remains a public health threat in many parts of the world and improved …

The Small Indian Mongoose (Herpestes Auropunctatus) On Adriatic Islands: Impact, Evolution, And Control, Arijana Barun

Doctoral Dissertations

ABSTRACT

One cause of declines and extinctions of island species is carnivore introduction. Four carnivores, including the small Indian mongoose (Herpestes auropunctatus), are on the IUCN’s list of 100 of the World's Worst Invasive Alien Species. My thesis summarizes global patterns of carnivore introductions and examines ecological, evolutionary, and management impacts of this mongoose. I study abundances of reptiles and amphibians on mongoose-infested and mongoose-free islands in the Adriatic Sea to determine if factors other than mongoose presence can account for abundance differences. For several reptiles and amphibians, the mongoose is implicated as causing differences. Additionally, I …

Islands, Metapopulations, And Archipelagos: Genetic Equilibrium And Non-Equilibrium Dynamics Of Structured Populations In The Context Of Conservation, Robert Graham Reynolds

Doctoral Dissertations

Understanding complex population dynamics is critical for both basic and applied ecology. Analysis of genetic data has been promoted as a way to reconstruct recent non-equilibrium processes that influence the apportioning of genetic diversity among populations of organisms. In a structured-deme context, where individual populations exist as geographically distinct units, island biogeography theory and metapopulation genetics predict that the demographic processes of extinction, colonization, and migration will affect the magnitude and rate of genetic divergence between demes. New methods have been developed to attempt to detect the influence of non-equilibrium dynamics in structured populations. I challenged two of these methods: …

Developmental Evolution Of The Progamic Phase In Nymphaeales, Mackenzie Lorraine Taylor

Doctoral Dissertations

The period between pollination and fertilization, or the progamic phase, is a critical life history stage in seed plants and innovations in this life history stage are hypothesized to have played an important role in the diversification of flowering plants. Over the course of this dissertation research, I investigated programic phase development in Nymphaeales (water lilies), an ancient angiosperm lineage that diverged from the basalmost or next most basal node of the angiosperm phylogenetic tree and that is represented in the oldest angiosperm fossil record. I used field experiments and microscopy to document pollination biology, breeding system, and reproductive developmental …

On The Evolution Of Codon Usage Bias, Premal R. Shah

Doctoral Dissertations

The genetic code is redundant, with most amino acids coded by multiple codons. In many organisms, codon usage is biased towards particular codons. A variety of adaptive and non-adaptive explanations have been proposed to explain these patterns of codon usage bias. Using mechanistic models of protein translation and population genetics, I explore the relative importance of various evolutionary forces in shaping these patterns. This work challenges one of the fundamental assumptions made in over 30 years of research: codons with higher tRNA abundances leads to lower error rates. I show that observed patterns of codon usage are inconsistent with selection …

An Investigation Of Stratigraphic Evidence For An Abrupt Climatic Event 8200 Yr Bp In Valle De Las Morrenas, Costa Rica, Brian Thomas Watson

Masters Theses

Lago de las Morrenas 4 (9.498056° [degrees] N, 83.486111° [degrees] W, 3466 m elev.) is the lowest lake in a chain of glacial lakes located in the Valle de las Morrenas, a valley facing almost due north from Cerro Chirripó, the highest peak in the Cordillera de Talamanca in Costa Rica. Coarse resolution analyses of pollen, microscopic charcoal, and loss-on-ignition of a ca. 10,000 year sediment record from Lago de las Morrenas 4 was carried out to complement and extend previous research on the environmental history of the Chirripó highlands and to provide context for high-resolution sampling and analysis of …

The Effects Of Resource Availability And Temperature On Ants, Carissa Michelle Chambers

Chancellor’s Honors Program Projects

No abstract provided.

Estimating Population Parameters Of The Louisiana Black Bear In The Upper Atchafalaya River Basin, Carrie Lynne Lowe

Masters Theses

In 1992, the Louisiana black bear (Ursus americanus luteolus) was granted threatened status under the Endangered Species Act primarily because of extensive habitat loss and fragmentation. Currently, the Louisiana black bear is restricted to 3 relatively small, disjunct breeding subpopulations located in the Tensas River Basin of northeast Louisiana, the upper Atchafalaya River Basin (ARB) of south-central Louisiana, and coastal Louisiana. The 1995 Recovery Plan mandates research to determine the viability of the remaining subpopulations. I conducted a capture-mark-recapture study during 2007–2009 to estimate population parameters for the ARB bear subpopulation by collecting hair samples (n = …

Using Stable Isotopes To Assess Longitudinal Diet Patterns Of Black Bears (Ursus Americanus) In Great Smoky Mountains National Park, Jennapher Lynn Teunissen Van Manen

Masters Theses

Long-term diet patterns based on stable isotope analysis may be helpful to understand changes in food selection of black bears (Ursus americanus) over time and guide management programs to reduce human-bear conflicts. An enriched stable carbon isotope signature indicates an anthropogenic food source in the diet and an enriched nitrogen signature indicates a higher tropic level for a species. I examined longitudinal feeding patterns from 117 hair samples of black bears live captured in Great Smoky Mountains National Park during 1980–2001 using stable carbon and nitrogen isotope analysis from hair samples. I developed a set of a priori …

Does Group Feeding By Toxic Prey Confer A Defensive Benefit? Aristolochic Acid Content, Larvae Group Size And Survival Of Pipevine Swallowtail (Battus Philenor) Larvae., Lauren Wisner Wilmoth

Masters Theses

Aggregative feeding is widespread in Lepidopteran larvae suggesting that this

behavior serves on adaptive function. Many studies of the potential benefits of

aggregative feeding in Lepidopteran larvae have been conducted. However, no studies

have directly examined the benefits of cryptic larvae being both chemically defended and

gregarious. Group feeding occurs disproportionately more in chemically defended

larvae than in larvae that have no chemical defense. Most of these larvae are cryptic

when they are most highly aggregated and most vulnerable to predation. In this study,

the benefits of group feeding in terms of decreased predation were explored in first instar

larvae …