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The Effect Of Genetic Relatedness On Mate Selection And Spatial Distribution In The American Alligator, Alligator Mississippiensis, Mark Hoog Jan 2023

The Effect Of Genetic Relatedness On Mate Selection And Spatial Distribution In The American Alligator, Alligator Mississippiensis, Mark Hoog

Electronic Theses and Dissertations

To date, most genetic studies on the American alligator (Alligator mississippiensis) have focused on population genetics and multiple paternity. There have not been any studies looking at how relatedness affects alligator behavior and movement. This study focused on three main questions: 1) what is the genetic diversity among alligators in this location? 2) can parentage be accurately defined among parents and offspring? and 3) how does individual relatedness affect their spatial distribution? We examined the relatedness of 174 unique individuals from the Okefenokee Swamp Park, in South Georgia, USA. In addition, we placed Telonics® satellite tags on …


Dna Methylation And The Response To Infection In Introduced House Sparrows, Melanie Gibson Jan 2023

Dna Methylation And The Response To Infection In Introduced House Sparrows, Melanie Gibson

Electronic Theses and Dissertations

Epigenetics is the study of molecular modification of a genome without changing its base pairs. The most studied type of epigenetic mechanism is DNA methylation, which is capable of turning a gene “on” or “off.” Epigenetic potential is the capacity to which an individual can have methylation on its genome. The more CpGs available, the greater the epigenetic potential. In invasive species, genetic variation has been observed to be paradoxical: not much of it exists on a genomic level, but epigenetically, phenotypic variation can occur. The focus on shift in gene expression in this study is on Toll-Like Receptor 4 …


Population Genomics Of Redbreast Sunfish (Lepomis Auritus): Exploring Gene Flow And Local Adaptation In A Widely Distributed Freshwater Fish, Garret J. Strickland Jan 2022

Population Genomics Of Redbreast Sunfish (Lepomis Auritus): Exploring Gene Flow And Local Adaptation In A Widely Distributed Freshwater Fish, Garret J. Strickland

Electronic Theses and Dissertations

Little information is available concerning the distribution of genetic diversity in non-salmonid, non-imperiled, freshwater fish. In order to fill in this knowledge gap, I conducted a population genomics survey in Redbreast Sunfish (Lepomis auritus; RBS), a widespread, generalist species distributed along the Atlantic slope rivers of eastern North America. I sampled four basins (ACF, Savannah, Roanoke, and James) at eight sites each with a factorial experimental design. Sites were distributed among coastal plain, Piedmont, or mountain ecoregions in order to capture the greatest range of environmental states experienced by RBS, with the intention of finding evidence for local adaptation to …


Amblyomma Quadricavum (Schulze, 1941) (Acari:Ixodidae): First Description Of The Nymphal Stage And Phylogenetic Assessment Of Its Taxonomic Status, Ashleigh V. Riggs Jan 2022

Amblyomma Quadricavum (Schulze, 1941) (Acari:Ixodidae): First Description Of The Nymphal Stage And Phylogenetic Assessment Of Its Taxonomic Status, Ashleigh V. Riggs

Electronic Theses and Dissertations

The hard tick (Acari: Ixodidae) Amblyomma quadricavum (Schulze, 1941) is a parasite of snakes and is endemic to the Caribbean region. Morphological characters of this species, namely its rudimentary eye structures, have led to debate about its taxonomic status. The species was originally assigned to the genus Aponomma. However, with revisions of the genus Aponomma, and the recent creation of new genera created for some basal former-Aponomma, it has been suggested that perhaps Amblyomma quadricavum might be a close relative of Robertsicus elaphensis, the Trans-Pecos rat snake tick of the southwest United States and New Mexico, another eyeless former-Aponomma species …


Applying Conservation Genomic Techniques To Guide Management Of The Reticulated Flatwoods Salamander (Ambystoma Bishopi), Miranda Gaupp Jan 2022

Applying Conservation Genomic Techniques To Guide Management Of The Reticulated Flatwoods Salamander (Ambystoma Bishopi), Miranda Gaupp

Electronic Theses and Dissertations

The Reticulated flatwoods salamander (Ambystoma bishopi) is a federally endangered amphibian endemic to the longleaf-pine ecosystem of the southeastern U.S. This study used analyses of single-nucleotide polymorphism (SNP) data, collected from 2,255 unique individuals across 5 breeding seasons, spread across the known extant range of A. bishopi, to characterize the genetic diversity and demographics of populations, genetic relationships among populations, and patterns and spatial extents of gene flow, and to evaluate potential effects of management on A. bishopi’s resiliency. Population structure was strongly hierarchical, with individual breeding ponds (n = 38) acting as semi-connected subpopulations …


Florida Sand Skink And Blue-Tailed Mole Skink: Expanding Geographic Coverage Of Genetic Analysis For Conservation, Emma Simpson Jan 2022

Florida Sand Skink And Blue-Tailed Mole Skink: Expanding Geographic Coverage Of Genetic Analysis For Conservation, Emma Simpson

Electronic Theses and Dissertations

The Lake Wales Ridge is important scrub habitat that has been increasingly altered since the post-Columbian settlement in Florida. This loss of habitat has caused extreme anthropogenic fragmentation within the Lake Wales Ridge resulting in isolation among extant scrub patches. To expand the geographic scope of previous studies and answer questions concerning population connectivity, we characterized genetic diversity and differentiation using cytochrome-b and microsatellite genetic markers for two endemic skink species: the Florida Sand Skink (Plestiodon reynoldsi) and Blue-tailed Mole Skink (Plestiodon egregius lividus). Both species display historical isolation between central and southern Lake Wales Ridge …


Creating A Georgia Southern Spider Collection: Can Dna Barcoding Help?, Guy B. Hobbs Jan 2021

Creating A Georgia Southern Spider Collection: Can Dna Barcoding Help?, Guy B. Hobbs

Electronic Theses and Dissertations

With over 280 spider (Araneae) species recorded within the State of Georgia, USA, the need for a well-documented natural history collection with a usable voucher system is critical to continually assess spider diversity and their future ecological impact in this region. Spider identification can be daunting for the inexperienced taxonomist; it is time consuming and sometimes requires destructive procedures. Previous works have successfully used an alternative method, DNA barcoding, to correctly identify spider species while preserving their morphology. This study set forth to create the core of a well-documented spider collection within Georgia Southern University’s Institute for Coastal Plain Science …


Comparative Conservation Genomics Of A Suite Of Imperiled Freshwater Mussels, Scott C. Meyer Jan 2021

Comparative Conservation Genomics Of A Suite Of Imperiled Freshwater Mussels, Scott C. Meyer

Electronic Theses and Dissertations

Maintenance of genetic diversity is a critical component to the management and recovery of imperiled species. By ensuring that a species’ genetic diversity is maintained, issues like inbreeding depression and loss of local adaptation can be prevented. However, the genetic diversity of many species are not well-characterized, and the factors that influence a species’ genetic diversity are often not well understood. In the case of imperiled unionid freshwater mussels, it is important to conduct conservation genetic assessments to aid in their management and preserve genetic diversity. This is the first study to conduct a comparative conservation genomic assessment for eight …


Disease Prevalence And The Population Genetic Structure Of Crassostrea Virginica Along The Georgia Coast, Sarah Batchelor Jan 2021

Disease Prevalence And The Population Genetic Structure Of Crassostrea Virginica Along The Georgia Coast, Sarah Batchelor

Electronic Theses and Dissertations

The Eastern Oyster, Crassostrea virginica, is an ecologically important species that plays a role in protecting shorelines, water filtration, and providing habitat and food for various fish species. Perkinsus marinus and Haplosporidium nesloni are two pathogens currently affecting oyster populations. These pathogens have both been documented as causes of mass mortality events along the East coast. They greatly diminish the health of oysters, resulting in the degradation of oyster tissue, reduction in growth and reproductive ability, and may cause death. In this study, wild oysters were collected from eleven locations along the Georgia coast to investigate the presence, intensity, …


Plasticity And The Impact Of Increasing Temperature On A Tropical Ectotherm, Adam A. Rosso Jan 2020

Plasticity And The Impact Of Increasing Temperature On A Tropical Ectotherm, Adam A. Rosso

Electronic Theses and Dissertations

Organisms may respond to climate change through behavior, genetic adaptation, and/or phenotypic plasticity. Tropical ectotherms are thought to be especially vulnerable to climate change because most have a narrow range of thermal tolerance while living close to their upper thermal tolerance limits. Additionally, many tropical species live in closed-canopy forests, which provide homogenous thermal landscapes that prevent behavioral compensation for stressfully warm temperatures. Finally, tropical ectotherms are thought to have decreased capacity for phenotypic plasticity because they have evolved in thermally stable environments. We tested gene expression patterns and phenotypic plasticity in the Panamanian slender anole by a) measuring changes …


Impact Of Seasonal And Host-Related Factors On The Intestinal Microbiome And Cestode Community Of Sorex Cinereus And Sorex Monticola, Katelyn D. Cranmer Jan 2019

Impact Of Seasonal And Host-Related Factors On The Intestinal Microbiome And Cestode Community Of Sorex Cinereus And Sorex Monticola, Katelyn D. Cranmer

Electronic Theses and Dissertations

The intestinal microbiome of mammals plays a significant role in host health and response to environmental stimuli and can include both beneficial native bacteria as well as parasitic worms. In this study, I examined the intestinal cestode and bacterial communities of two closely related species of shrew, Sorex monticola and Sorex cinereus, over a six month period in 2016. Specimens were collected approximately every three weeks from May to October from the Sangre de Cristo Mountains in Cowles, New Mexico. A total of 79 shrews were prepared with the gastrointestinal tracts removed and flash-frozen in liquid nitrogen. An additional …


Quantifying Genetic Responses Of Plants To Drought Stress With A Comparative Transcriptome Approach, Jessica K. Devitt Jan 2018

Quantifying Genetic Responses Of Plants To Drought Stress With A Comparative Transcriptome Approach, Jessica K. Devitt

Electronic Theses and Dissertations

Mentzelia section Bartonia (Loasaceae) commonly occurs in some of the hottest and driest places in North America, but we poorly understand the mechanisms that allow them to tolerate such extreme environments. Morphological and physiological adaptations are well studied in model organisms. The underlying genetic responses to drought stress in non-model organisms like Mentzelia is unknown. To better understand and identify differences and similarities in genetic responses to drought stress between species existing in different habitats with differing water availability, three species from the genus Mentzelia were compared. Species of section Bartonia occur across an environmental gradient, from temperate to arid …


Movement In Cats, Valerie N. Plummer Jan 2018

Movement In Cats, Valerie N. Plummer

Electronic Theses and Dissertations

Feral cats (Felis catus) are listed as one of the '100 world's worst invasive alien species'. There are as many as 70-100 million feral cats in the United States as well as an estimated 117-157 million domestic indoor and outdoor cats. Management efforts include a nonlethal feeding and sterilization program known as "trap-neuter-release" (TNR) where cats are surgically sterilized and returned to the environment. Population size and structure, immigration rates, spay/neuter rates, and data on spatial use all play a role in whether TNR is a viable management option. This study focuses on population structure and spatial use. …


Tissue Specificity Of Sex-Biased Gene Expression And The Development Of Sexual Dimorphism, Albert K. Chung Jan 2018

Tissue Specificity Of Sex-Biased Gene Expression And The Development Of Sexual Dimorphism, Albert K. Chung

Electronic Theses and Dissertations

One prominent form of phenotypic diversity in nature is the dramatic difference between males and females within a single species. A central genetic obstacle which must be overcome is that two distinct phenotypes must be produced from a single, shared genome. One genetic mechanism that is of particular import that would allow sexes to overcome the limitation of a shared genome is sex-specific regulation of gene expression. Although sex-biased gene expression is generally predicted to increase over ontogeny as male and female phenotypes diverge, this pattern should be most pronounced in tissues that contribute to the most extreme aspects of …


Dynamics Of Gene Networks In Cancer Research, Paul Scott Jan 2017

Dynamics Of Gene Networks In Cancer Research, Paul Scott

Electronic Theses and Dissertations

Cancer prevention treatments are being researched to see if an optimized treatment schedule would decrease the likelihood of a person being diagnosed with cancer. To do this we are looking at genes involved in the cell cycle and how they interact with one another. Through each gene expression during the life of a normal cell we get an understanding of the gene interactions and test these against those of a cancerous cell. First we construct a simplified network model of the normal gene network. Once we have this model we translate it into a transition matrix and force changes on …


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 …


A Population Genetic Investigation Of The Reticulated Flatwoods Salamander (Ambystoma Bishopi) On Eglin Air Force Base, Alexander S. Wendt Jan 2017

A Population Genetic Investigation Of The Reticulated Flatwoods Salamander (Ambystoma Bishopi) On Eglin Air Force Base, Alexander S. Wendt

Electronic Theses and Dissertations

The reticulated flatwoods salamander (RFS) is an endangered salamander with a unique life history. One of the largest known, best studied refuges for RFS is found on Eglin Air Force Base, and these RFS have been sampled and managed extensively since 2010. My thesis seeks to better understand RFS by using genetic techniques to address several unknowns, including: 1) determining the population structuring of RFS and the manageable units for species conservation, 2) estimating the size and status of populations, 3) understanding dispersal of RFS and factors that influence this, 4) exploring the breeding biology and recruitment patterns of RFS …


The Behavioral, Biochemical And Genetic Effects Of Sleep Deprivation In Zebrafish (Danio Rerio), Jade Catherine Boykin Jan 2016

The Behavioral, Biochemical And Genetic Effects Of Sleep Deprivation In Zebrafish (Danio Rerio), Jade Catherine Boykin

Electronic Theses and Dissertations

Vertebrate sleep is a universal phenomenon and encompasses an array of conserved behavioral and physiological characteristics. Studies of sleep in humans have shown that sleep deprivation leads to adverse effects to human health and additional stress. Teleosts have emerged as a useful model species to study the vertebrate stress response, given its stress axis has high levels of homology with the mammals, including humans. For this study, the behavior of zebrafish (Danio rerio) subjected to acute (24 hours) and chronic (20 days) extended light exposure was monitored and whole-body cortisol was analyzed as an indication of activation of …


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 …


Helping To Resolve Taxonomic Conflicts Within The Genus Amblyomma (Acari:Ixodidae) From A Molecular Perspective, Paula Lado Jan 2015

Helping To Resolve Taxonomic Conflicts Within The Genus Amblyomma (Acari:Ixodidae) From A Molecular Perspective, Paula Lado

Electronic Theses and Dissertations

This work sought to reassess the taxonomic status of Amblyomma parvum Aragao, 1908 and of the A. maculatum group of ticks Camicas, 1998. By using different molecular markers, 12SrDNA, 16SrDNA, DL, COI, COII (mitochondrial) and ITS2 (nuclear), I analyzed the systematic relationships between these taxa and their closest relatives. Phylogenetic analyses by maximum parsimony, maximum likelihood, and Bayesian analysis were performed in order to determine relationships among species and populations, and to determine the evolutionary history of these ixodids. The data obtained supported the hypothesis of cryptic speciation occurring within A. parvum, with the northern populations of Central America being …


The Role Of Artificial Structures In Facilitating Range Expansion Of The Introduced Barnacle Megabalanus Coccopoma In The Southeastern U.S.A., Alicia M. Reigel Jan 2015

The Role Of Artificial Structures In Facilitating Range Expansion Of The Introduced Barnacle Megabalanus Coccopoma In The Southeastern U.S.A., Alicia M. Reigel

Electronic Theses and Dissertations

The barnacle Megabalanus coccopoma is a recent invader of the southeastern U.S.A. from the tropical eastern Pacific. In Georgia, M. coccopoma populations along the immediate coastline often suffer extensive mortality during the winter, but population rebuilding is common after these events suggesting that there may be nearby larval sources. I investigated the hypothesis that artificial structures (i.e., buoys, towers), occurring far enough offshore of Georgia for water temperatures to be moderated by the Gulf Stream, provide refuges for breeding adults of M. coccopoma and can serve as the larval source. I investigated this hypothesis by first developing thirteen microsatellite primer …


Genetic Structure Of Ixodes Scapularis Say 1821 (Acari: Ixodidae), The Blacklegged Tick, By Microsatellite Analysis, John Ludwig Jan 2015

Genetic Structure Of Ixodes Scapularis Say 1821 (Acari: Ixodidae), The Blacklegged Tick, By Microsatellite Analysis, John Ludwig

Electronic Theses and Dissertations

The blacklegged tick, Ixodes scapularis (Acari: Ixodidae) is the subject of intense research due to its economic importance from being a vector of several diseases. Previous studies have examined its taxonomic status and more recently, its genetic structure. This study embarked upon resolving the questions surrounding the genetic structuring of the tick, by using different molecular markers. Molecular data were first phylogenetically analyzed by using four different mitochondrial and nuclear markers (12SrDNA n=483, Dloop n=432, ITS2 n=156, Actin n=117). A Bayesian tree was inferred from the concatenated mitochondrial dataset, whereas nuclear gene markers were found to be uninformative. Nine microsatellites …


Epistasis In Predator-Prey Relationships, Iuliia Inozemtseva Jan 2014

Epistasis In Predator-Prey Relationships, Iuliia Inozemtseva

Electronic Theses and Dissertations

Epistasis is the interaction between two or more genes to control a single phenotype. We model epistasis of the prey in a two-locus two-allele problem in a basic predator- prey relationship. The resulting model allows us to examine both population sizes as well as genotypic and phenotypic frequencies. In the context of several numerical examples, we show that if epistasis results in an undesirable or desirable phenotype in the prey by making the particular genotype more or less susceptible to the predator or dangerous to the predator, elimination of undesirable phenotypes and then genotypes occurs.


Soil Microbial Community Distributions And Disease Suppressiveness In The Coastal Plain Of Georgia, Michael J. Sabula Jan 2014

Soil Microbial Community Distributions And Disease Suppressiveness In The Coastal Plain Of Georgia, Michael J. Sabula

Electronic Theses and Dissertations

This study compared the soil microbial communities of three vegetation types in the coastal plain of Georgia: 1. crop land actively in use for agricultural production, 2. transitional grassland in early stages of secondary succession, and 3. pristine unmanaged forest land. Microbial species diversity and quantities of microbial DNA were determined from each of these vegetation types at three separate locations near Statesboro, Georgia. Length heterogeneity PCR(LH-PCR) methods and subsequent analysis of fungal, bacterial, and metazoan communities by analysis of similarity (ANOSIM) revealed high within-group similarity by vegetation type, indicating land management intensity and vegetation cover is a strong determining …


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 …


Assortative Mating In Ixodes Scapularis (Acari: Ixodidae) Ticks? And Ixodes Scapularis Infest Male Deer More Often Than Female Deer At Savannah River Site, (Aiken, Sc), Jenny Dickson Apr 2013

Assortative Mating In Ixodes Scapularis (Acari: Ixodidae) Ticks? And Ixodes Scapularis Infest Male Deer More Often Than Female Deer At Savannah River Site, (Aiken, Sc), Jenny Dickson

Electronic Theses and Dissertations

In this study we explored the hypothesis that the mitochondrial genetic diversity observed in Ixodes Scapularis ticks in the Southeastern United States is maintained through assortative mating. The study of 319 couples of ticks collected in copula from deer at the Savannah River Site (Aiken, SC) showed that ticks assigned to mitochondrial (12SrDNA and d-loop genes) phylogenetic monophyletic clades do not chose their mating partner based on genetic similarity or genetic diversity. The genetic composition of couples did not differ significantly from random choice. Our data indicate that if genetic diversity is maintained in this tick population, this cannot be …


Variation In Egg Components: A Study Of Maternal Investment And Resource Partitioning In The Nesting Loggerhead Sea Turtle; Estimating Genic Variation And Mapping Genetic Lineage Of A Rare Captive Helodermatid Population: Heloderma Horridum Charlesbogerti, Ketan V. Patel Apr 2013

Variation In Egg Components: A Study Of Maternal Investment And Resource Partitioning In The Nesting Loggerhead Sea Turtle; Estimating Genic Variation And Mapping Genetic Lineage Of A Rare Captive Helodermatid Population: Heloderma Horridum Charlesbogerti, Ketan V. Patel

Electronic Theses and Dissertations

Loggerhead sea turtles have the highest egg yields of any oviparous non-avian reptiles. Blood urea nitrogen levels increased as the season progressed while total blood albumen and total protein levels decreased. Wet egg mass (H = 1.7719 df = 2 p = 0.0375*) and albumen mass (H = 6.0507 df = 2 p = 0.0485*) significantly decreased across the nesting season however, wet yolk did not. Analysis of dried egg components showed that dry yolk and albumen did not differ across the nesting season. In addition on no seasonal change in dried egg components, hatchling size was conserved across the …


The Tick Genus Amblyomma In Africa: Phylogeny And Mutilocus Dna Barcoding, Omobolanle Kushimo Jan 2013

The Tick Genus Amblyomma In Africa: Phylogeny And Mutilocus Dna Barcoding, Omobolanle Kushimo

Electronic Theses and Dissertations

The tick genus Amblyomma includes approximately 130 species, 28 of which are found on the African continent and/ or in Madagascar. In order to understand the evolutionary phylogeography of the genus, it is necessary to gain a better understanding of the relationships between African taxa. Therefore, the main goals of this work were to, (1) reconstruct the phylogenetic relationships of the African Amblyomma available to us and (2) test markers for their usefulness as barcoding tools to link unknown immature specimens to their corresponding adults. The mitochondrial gene markers used in this study (12SrDNA and COI) did not resolve the …