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Full-Text Articles in Life Sciences

Primate Proteomic Composition Of Seminal Plasma And Prostate-Specific Transglutaminase Activity In Relation To Sexual Selection., Amanda M.C. Zielen Jan 2017

Primate Proteomic Composition Of Seminal Plasma And Prostate-Specific Transglutaminase Activity In Relation To Sexual Selection., Amanda M.C. Zielen

Electronic Theses and Dissertations

Humans (Homo sapiens), chimpanzees (Pan troglodytes), and gorillas (Gorilla gorilla) have diverse mating systems with varying levels of sperm competition. Several seminal plasma genes have been claimed to evolve under positive selection, while others are altered or lost. This study aims to identify biologically relevant differences among seminal plasma proteomes of primates in relation to mating systems and previous genomic studies. Seminal plasma from three individuals of each species were run in triplicate in shotgun liquid chromatography – tandem mass spectrometry (LC-MS/MS) and confirmed with Western blots. Over 7,000 peptides were identified across all …


Evolutionary Linkage Of Mimetic And Non-Mimetic Color Traits In A Coral Snake Mimicry Complex, John D. Curlis Jr Jan 2017

Evolutionary Linkage Of Mimetic And Non-Mimetic Color Traits In A Coral Snake Mimicry Complex, John D. Curlis Jr

Electronic Theses and Dissertations

Color polymorphism in aposematic mimicry systems is a perplexing phenomenon for evolutionary biologists, as theoretically the benefits of converging on a model phenotype should constrain the evolution of phenotypic diversity in these systems (i.e., color polymorphism should not occur). Nevertheless, color polymorphism in mimicry systems is prevalent throughout many taxa. In some of these systems, the evolution of color polymorphism results in the existence of non-mimetic morphs, such as those that are cryptic. The case of ground snakes (Sonora semiannulata) is unique in that color polymorphism encompasses both mimetic and cryptic morphs, as well as individual mimetic and …


Sources Of Ecologically Important Trait Variation In Mosquitofish (Gambusia Affinis And Gambusia Holbrooki), Heather Ann Arnett Apr 2016

Sources Of Ecologically Important Trait Variation In Mosquitofish (Gambusia Affinis And Gambusia Holbrooki), Heather Ann Arnett

Electronic Theses and Dissertations

The study of contemporary evolution and eco-evolutionary dynamics is classically defined in terms of genetic evolution, but the actual suite of processes driving contemporary trait change is likely much more complex than often credited. This dissertation considers additional mechanisms of trait change that might be important to an emerging model system for study of contemporary evolution and eco-evolutionary dynamics. Specifically, the research focuses on phenotypically plastic and demographic trait variation in Eastern and Western Mosquitofish (Gambusia affinis and G. holbrooki) facing the major ecological gradient of predation risk. Plasticity experiments employed a common-garden rearing design to manipulate fish …


The Ecology And Evolution Of Rare, Soil Specialist Astragalus Plants In The Arid Western U.S., Joseph M. Statwick Jan 2016

The Ecology And Evolution Of Rare, Soil Specialist Astragalus Plants In The Arid Western U.S., Joseph M. Statwick

Electronic Theses and Dissertations

Organisms that specialize in uncommon habitats are, by their very nature, inherently uncommon. Specialization has its advantages, namely reduced competition and predation, but it also incurs costs. Specialists often have small population sizes, narrow ranges, and fragmented habitat, all of which engender negative consequences on an evolutionary timescale. Herein, I examine benefits and costs of specialization in selenium-hyperaccumulating plants in the genus Astragalus (Fabaceae). These plants are disproportionately likely to be rare and of conservation concern. Thus, I optimized germination pretreatments for Astragalus species such that seed loss can be minimized during ex situ cultivation, and found that physical scarification …


Biogeographical Patterns In The Hard-Tick Genus Amblyomma Koch 1844 (Acari: Ixodidae), Matthew H. Seabolt Jan 2016

Biogeographical Patterns In The Hard-Tick Genus Amblyomma Koch 1844 (Acari: Ixodidae), Matthew H. Seabolt

Electronic Theses and Dissertations

Amblyomma Koch is a genus of hard-ticks with approximately 130 species. Its geographical range is typical for organisms with a Gondwanan origin. A majority of these species are endemic to the Neo- and Afrotropical regions, with the remaining taxa dispersed throughout Southeast Asia, Australia and the Pacific islands. Based on this distribution, we hypothesize that the genus dispersal patterns will mirror the fragmentation and continental drift of the Gondwanan supercontinent. Maximum parsimony, maximum likelihood, Bayesian inference and node-dating analyses of nuclear 18S rDNA gene sequences reveal a more recent origin and radiation patterns within the genus and suggest that Amblyomma …


Explaining Migratory Behaviors Using Optimal Migration Theory, Jennifer D. Mccabe Dec 2015

Explaining Migratory Behaviors Using Optimal Migration Theory, Jennifer D. Mccabe

Electronic Theses and Dissertations

Bird migration is the regular seasonal movements between breeding and nonbreeding grounds. In general, birds that breed in the Northern Hemisphere tend to migrate northward in the spring to take advantage of increasing insect populations and lower predation pressures and fly south when food availability and weather conditions decline. Embarking on a journey that can stretch a thousand miles round trip is a dangerous and arduous undertaking. While en route migrants must stop and feed to replenish their depleted energy reserves, often in unfamiliar locations with unknown predation pressures. They also must react to weather conditions during flight and while …


A Systematic Review Of The Soricimorph Eulipotyphla (Soricidae: Mammalia) From The Gray Fossil Site (Hemphillian), Tennessee, Joshua Doby May 2015

A Systematic Review Of The Soricimorph Eulipotyphla (Soricidae: Mammalia) From The Gray Fossil Site (Hemphillian), Tennessee, Joshua Doby

Electronic Theses and Dissertations

Due in part to the incompleteness of the Cenozoic fossil record in the eastern U.S., the evolution and immigration of shrews (Soricidae) is not well understood. A rich soricid fauna from the Gray Fossil Site (GFS), Washington County, TN, has enabled many new inferences to be made. There are 7 new species in 6 genera: Paenelimnoecus, “Blarinella”, Petenyia, Tregosorex, Crusafontina, and Gen et sp. nov. GFS species of the genera Paenelimnoecus, “Blarinella”, and Petenyia are the first occurrence of each genus in the New World. Tregosorex, Crusafontina, and the N.A. taxon Limnoecus all have their latest documented occurrence at the …


Nonstructural Carbohydrate Concentrations Of Pine Trees As A Function Of Evolutionary History, Joshua T. Mims Jan 2015

Nonstructural Carbohydrate Concentrations Of Pine Trees As A Function Of Evolutionary History, Joshua T. Mims

Electronic Theses and Dissertations

Nonstructural carbohydrates (NSC) can supply substrate during periods when current photosynthate is unavailable or inadequate to meet metabolic demands. I hypothesized that natural selection has favored higher nonstructural carbohydrate concentrations ([NSC]) in species that have an evolutionary history of frequent disturbance and tested this using three southern pine species that have evolved under a continuum of disturbance frequencies (evolutionary history of fire ~ longleaf > slash > loblolly). Stem and root samples were collected from 12 similar-sized individual trees of each species during time periods that reflect the annual minimum and maximum [NSC]. A modified colorimetric method was performed on the samples …


Inter-And Intra-Population Variability Across The Transcriptome Of Lake Baikal’S Endemic Copepod With Ramifications For Adapting To Climate Change, Larry L. Bowman Jr May 2014

Inter-And Intra-Population Variability Across The Transcriptome Of Lake Baikal’S Endemic Copepod With Ramifications For Adapting To Climate Change, Larry L. Bowman Jr

Electronic Theses and Dissertations

The future of Lake Baikal’s biodiversity is uncertain in response to climate change. Unlike its diverse benthos, Lake Baikal’s zooplankton is species poor, with up to 96% of its biomass being composed of a single Calanoid copepod species, Epischura baikalensis. This study characterizes the genetic differentiation and differential gene expression of E. baikalensis. Using partial-transcriptome sequences obtained by 454 Rosche and Illumina sequencing technologies, the genetic differentiation at inferred single nucleotide polymorphism (SNP) sites and differential gene expression in populations sampled from various parts of the lake were analyzed. The functional genomics of genes showed significant differential …


The Prevalence And Effect Of Wolbachia Infection On The Brown Widow Spider (Latrodectus Geometricus), Brittany Dane' Arrington Jan 2014

The Prevalence And Effect Of Wolbachia Infection On The Brown Widow Spider (Latrodectus Geometricus), Brittany Dane' Arrington

Electronic Theses and Dissertations

Wolbachia was recently identified in the Brown Widow Spider (Latrodectus geometricus). This symbiont has not previously been found in this genus, therefore the consequences on the host’s population dynamics are unknown. The frequency of endosymbiont infection can provide insight into the population dynamics of the host as this bacteria is known to alter host life history. In my 1st chapter I determine the prevalence of Wolbachia pipentis infection in in the Brown Widow Spider (Latrodectus geometricus) from five locations in the Southeastern United States. Infection frequency differed significantly among sampling locations, ranging from 20% to …


Phenotypic Variation In Native North American And Invasive Chinese Populations Of Plantago Virginica, Teresa E. Popp Jan 2014

Phenotypic Variation In Native North American And Invasive Chinese Populations Of Plantago Virginica, Teresa E. Popp

Electronic Theses and Dissertations

Alien plant species can cause significant economic and biological destruction by invading new environments and outcompeting native species. Through experimental research, the mechanisms by which these species invade can be better understood and applied to their management. Plantago virginica is a perennial herb, native to North America that has recently invaded China. It has been known to reduce crop growth and harbor diseases in the introduced range. A common garden study was conducted at the Georgia Southern University greenhouse, comparing twenty populations of P. virginica from both the native North American and invasive Chinese ranges. I examined if there were …


Tactical Escape Behavior And Performance Of A Small Sceloporine Lizard In Two High Risk Habitats, Seth Parker Jan 2014

Tactical Escape Behavior And Performance Of A Small Sceloporine Lizard In Two High Risk Habitats, Seth Parker

Electronic Theses and Dissertations

The negotiation of uneven and complex terrain has implications for many small terrestrial vertebrates. Variation in the running surface due to obstacles like woody debris or vegetation can alter escape paths and running performance. Additionally, these microhabitat features can influence behavioral tactics in complex environments. The ability to negotiate physical barriers in dense environments likely influences survivorship through important ecological tasks, such as finding mates, foraging, and evading predators. The Florida scrub lizard (Sceloporus woodi) is a small, rare species endemic to two distinct and structurally complex environments in Florida, i.e. sand-pine scrub and longleaf pine-wiregrass sand-hills. The …


A Glyptosaurine Lizard From The Eocene (Late Uintan) Of San Diego, California, And Implications For Glyptosaurine Evolution And Biogeography, David Moscato Aug 2013

A Glyptosaurine Lizard From The Eocene (Late Uintan) Of San Diego, California, And Implications For Glyptosaurine Evolution And Biogeography, David Moscato

Electronic Theses and Dissertations

Glyptosaurinae is an extinct subfamily of lizards of the family Anguidae. Glyptosaurine lizards are known exclusively from the Paleogene of North America and Eurasia, reaching their peak of diversity and distribution in the Eocene. In North America these lizards are largely restricted to the intermontane basins along the Rocky Mountain range, with only sparse, indeterminately-identified skeletal elements known from outside of this region. Glyptosaurine lizards are split into two tribes: the monophyletic Glyptosaurini and paraphyletic “Melanosaurini”. Within Glyptosaurini, the most common and widespread genus is Glyptosaurus. In this study I describe a new specimen assignable to G. sylvestris, …


Natural Selection And Its Interactions With Migration And Population Demography: Experiments In Wild Guppy Populations, Dylan Jones Weese Aug 2010

Natural Selection And Its Interactions With Migration And Population Demography: Experiments In Wild Guppy Populations, Dylan Jones Weese

Electronic Theses and Dissertations

In this dissertation I quantify spatial and temporal variation in the pattern and strength of natural selection in wild populations of Trinidadian guppies (Poecilia reticulata), and assess the demographic costs of ongoing contemporary evolution in the form of selection against migrants. First, I describe the results often mark-recapture experiments to test hypotheses concerning the role of natural selection in geographic patterns of trait variation. Previous work has reported that guppies inhabiting high- and low-predation sites differ in both body shape and color. These patterns of phenotypic variation have been theorized to reflect differences in the balance between functional trade-offs among …