Life Sciences Commons^™

Analysis Of The Population Structure And Migrationhabits Of The Northern Leopard Frog (Lithobates Pipiens) At Midewin National Tallgrass Prairie, Gretchen A. Brinkman

ELAIA

Massive amphibian declines of recent years have pushed researchers to pursue population genetics surveys and assess the status of these essential components of many ecosystems. The Northern Leopard Frog (Lithobates pipiens) has continuously experienced population declines across the continental United States due to a combination of habitat losses and environmental changes. Midewin National Tallgrass Prairie houses a considerable portion of L. pipiens in Illinois, and the two creek watersheds studied within this location provide ideal conditions to support these animals. Because this prairie restoration project is a relatively recent development, further assessments regarding the population structure and degree of migration …

Range-Wide Analysis Of The Genetic Diversity And Genetic Structure Of The Spotted Turtle (Clemmys Guttata), Madison S. Whitehurst

Theses and Dissertations

Understanding the spatial distribution of genetic diversity and structure in endangered species is vital for effective conservation management. This research discusses the results of an initial analysis of the genetic structure and variation of the spotted turtle (Clemmys guttata), a species of conservation interest. The study sampled 913 individuals from 78 unique locales across 16 states in the eastern portion of the species' range. Utilizing ddRADSeq, a de novo genome assembly was developed to identify nearly 20,000 potential loci. A total of 926 were selected for this analysis. Results revealed no spatial clustering of genetic diversity or structure, …

Genetic Effects Of Anthropogenic Disturbance On Native Charrs, Brad Erdman

Electronic Theses and Dissertations

Artificial propagation has been utilized for over a century to offset anthropogenic declines of abundance for many fishes. Complex and poorly documented histories of habitat degradation and stockings have resulted in considerable uncertainty regarding whether contemporary populations are of native, hatchery, or mixed origins. This uncertainty is problematic as it precludes prioritizing the conservation of native populations that are postulated to possess local adaptations and greater evolutionary potential. Population genetics can assess the relative reproductive contributions of previous stocking events and in this dissertation I apply these methods to four empirical studies of native charr (genus Salvelinus) that have …

Characterization Of The Immunoglobulin Lambda Chain Across Diverse Human Populations., William Gibson

Electronic Theses and Dissertations

The adaptive immune system relies on a diverse set of over one hundred immunoglobulin (IG) genes across three genomic loci that are variably combined to form antibodies (Ab). The IG Lambda locus is one of two loci which encodes the IG light chain. The complexity of the IGL locus severely limits the effective use of standard short-read sequencing, limiting our knowledge of population diversity in these loci. We leveraged single molecule real-time (SMRT) long-read sequencing in conjunction with IGL-targeted DNA capture to develop the method IG-Cap for accurate and high-throughput sequencing of the IGL locus. We benchmarked this method using …

A Foundational Population Genetics Investigation Of The Sexual Systems Of Solanum (Solanaceae) In The Australian Monsoon Tropics Suggests Dioecious Taxa May Benefit From Increased Genetic Admixture Via Obligate Outcrossing, Jason T. Cantley, Ingrid E. Jordon-Thaden, Morgan Roche, Daniel S. Hayes, Stephamie Kate, Christopher T. Martine

Faculty Journal Articles

Solanum section Leptostemonum is an ideal lineage to test the theoretical framework regarding proposed evolutionary benefits of outcrossing sexual systems in comparison to cosexuality. Theoretically, non-cosexual taxa should support more genetic diversity within populations, experience less inbreeding, and have less genetic structure due to a restricted ability to self-fertilize. However, many confounding factors present challenges for a confident inference that inherent differences in sexual systems influence observed genetic patterns among populations. This study provides a foundational baseline of the population genetics of several species of different sexual systems with the aim of generating hypotheses of any factor—including sexual system—that influences …

Analysis Of The Population Structure And Migration Habits Of The Northern Leopard Frog (Lithobates Pipiens) At Midewin National Tallgrass Prairie, Gretchen A. Brinkman

Honors Program Projects

Massive amphibian declines of recent years have pushed researchers to pursue population genetics surveys and assess the status of these essential components of many ecosystems. The Northern Leopard Frog (Lithobates pipiens) has continuously experienced population declines across the continental United States due to a combination of habitat losses and environmental changes. Midewin National Tallgrass Prairie houses a considerable portion of L. pipiens in Illinois, and the two creek watersheds studied within this location provide ideal conditions to support these animals. Because this prairie restoration project is a relatively recent development, further assessments regarding the population structure and degree …

Landscape Genetics Of The Gulf Coast Tick, Amblyomma Maculatum, Sara Simmons Benham

Biological Sciences Theses & Dissertations

Connectivity among populations helps to maintain genetic diversity, population stability, and resilience. The Gulf Coast tick, Amblyomma maculatum, is a vector of the pathogen Rickettsia parkeri. Persistence of tick populations with high rates of R. parkeri infection poses health risks to humans and animals. Mitochondrial haplotypes were characterized by sequencing a fragment of the mitochondrial 16S rRNA gene. A comparative study of A. maculatum and Amblyomma americanum was conducted to identify similar and unique patterns between the species within the same region. Next, I compared A. maculatum sites across three different regions of the United States. This work …

Disparate Population And Holobiont Structure Of Pocilloporid Corals Across The Red Sea Gradient Demonstrate Species-Specific Evolutionary Trajectories, Carol Buitrago-López, Anny Cárdenas, Benjamin C.C. Hume, Thierry Gosselin, Fabian Staubach, Manuel Aranda, Daniel J. Barshis, Yvonne Sawall, Christian R. Voolstra

Biological Sciences Faculty Publications

Global habitat degradation heightens the need to better understand patterns of genetic connectivity and diversity of marine biota across geographical ranges to guide conservation efforts. Corals across the Red Sea are subject to pronounced environmental differences, but studies so far suggest that animal populations are largely connected, excepting evidence for a genetic break between the northern-central and southern regions. Here, we investigated population structure and holobiont assemblage of two common pocilloporid corals, Pocillopora verrucosa and Stylophora pistillata, across the Red Sea. We found little evidence for population differentiation in P. verrucosa, except for the southernmost site. Conversely, S. …

Fine-Scale Genetic Structure In Rhizosphere Microbial Communities Associated With Chamaecrista Fasciculata (Fabaceae), Mahboubeh Hosseinalizadeh Nobarinezhad, Lisa E. Wallace

Biological Sciences Faculty Publications

Soil microbiota of the rhizosphere are an important extension of the plant phenotype because they impact the health and fitness of host plants. The composition of these communities is expected to differ among host plants due to influence by host genotype. Given that many plant populations exhibit fine-scale genetic structure (SGS), associated microbial communities may also exhibit SGS. In this study, we tested this hypothesis using Chamaecrista fasciculata, a legume species that has previously been determined to have significant SGS. We collected genetic data from prokaryotic and fungal rhizosphere communities in association with 70 plants in an area of …

Invasion Of The Northeastern United States By The Southern Pine Beetle, Dendroctonus Frontalis, And The Impacts On Signatures Of Isolation By Distance Assessed Using Mitochondrial Dna, Lora Grace Holman

Honors Theses

The southern pine beetle (SPB) is a small, black beetle that parasitizes pine trees across the United States and Central America. Recently it has been recognized that the range of SPB is not limited to the southern United States, but rather extends northward across the eastern United States, which raises concerns for pine trees that have never encountered the pest before. Using mitochondrial DNA sequences from a section of the cytochrome oxidase I gene and four different measures of genetic distance compared to geographic distance, we tested for evidence of isolation by distance (IBD) among sampled SPB to see whether …

Molecular Evolution And Biogeography Of The New World Eptesicus Bats, Xueling Yi

Theses and Dissertations

Molecular evolution refers to a broad field of studies ranging from microevolution (e.g., population genetics) to macroevolution (e.g., phylogeny), including the bridging field of phylogeography. In natural populations, molecular studies are also combined with biogeography that links biological diversity with geographic distributions to provide a comprehensive understanding of evolutionary processes. The field of molecular evolution has been largely advanced from early exploratory descriptions to statistical tests on biological hypotheses and integrative analyses using sophisticated modeling. However, studies of molecular evolution still face some unresolved questions and challenges, especially in non-model systems. For example, the application of new technology has largely …

An Analysis Of The Spatial Genetic Structure Of A Hybrid Zone Between Two Species Of Killifish, Fundulus Heteroclitus And F. Grandis, Andrew Lee Hardy

UNF Graduate Theses and Dissertations

Hybridization offers unique insight into the evolutionary process of speciation and the forces that maintain barriers to reproduction. In northeast Florida, a hybrid zone between two species of killifish, Fundulus heteroclitus and F. grandis, has been identified near Flagler Beach, FL, although the exact boundaries of the hybrid zone remain unknown (Gonzalez et al. 2009). This study aims to determine the fine-scale spatial genetic patterns of the hybrid zone and test the hypothesis that species ranges are influenced by changes in dominant vegetation. Results from an ADMIXTURE analysis and F_ST data indicated the boundary of the area of …

Evaluating Population Genetic Structure And Potential Genomic Signals Of Natural Selection In A Migratory Songbird (Protonotaria Citrea), Tyler A. Hohenstein

Theses and Dissertations

In this study I attempted to further resolve the population genetic structure in the Prothonotary Warbler (Protonotaria citrea), and conducted an outlier SNP analysis and exploratory gene ontology analysis to investigate potential ongoing natural selection in the species. This analysis of population structure confirms previous work by DeSaix et al. (2019), where weak population structure was observed between eastern sites along the Atlantic Coastal Plain, and western sites in the Mississippi Alluvial Valley, possibly due to a genetic discontinuity across the Appalachian Mountains. I conducted two forms of outlier SNP analyses, a principal component analysis (PCA)-based approach to identify SNPs …

Implications Of Population Genetics And Physiological Responses On The Conservation Of Moose (Alces Alces Americana), Elias Rosenblatt

Graduate College Dissertations and Theses

Wildlife populations around the globe are facing numerous, complex challengesto their persistence, yet conservation efforts are hindered by limited information about these populations and the anthropogenic pressures they face. North American moose (Alces alces americana), despite being of ecological, cultural, and economical importance, inhabit remote landscapes, making population monitoring difficult. At the same time, many moose populations, including in Vermont and eastern North America, have experienced recent declines mainly due to winter tick (Dermacentor albipictus) epizootics. Anthropogenic landscape change and climate-mediated pressures pose future challenges for moose across the southern extent of their distribution. Though impacts of winter tick infestation …

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 …

Investigating The Genetic Diversity Of Immune Genes In Non-Native Populations Of American Bullfrogs (Rana Catesbeiana), Luisa Nereyda Segovia

Cal Poly Humboldt theses and projects

The American Bullfrog (Rana catesbeiana) is a highly invasive species that has successfully colonized habitats around the world. The genetic variability of immune genes within invasive populations, like that of bullfrogs, may contribute to how resistant a population is to pathogens. The objective of this project was to characterize the genetic diversity of an immune gene in invasive bullfrog populations in California to better understand how persistent these populations might be over time. To characterize immune gene variability, I isolated exon 2 of the Major Histocompatibility Complex (MHC) Class II Beta chain gene and a neutral mitochondrial marker, …

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 …

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 …

Microbial-Host Dynamics And The Evolution Of Nearshore Diversity In Hippocampus Abdominalis, Jimiane L. Ashe

Dissertations, Theses, and Capstone Projects

Local adaptation is a fundamental concept at the core of evolutionary process. Devising means to break down larger concepts and systematically test internal mechanisms are key to understanding the driving forces behind the influence of environmental differences on biological systems. To understand dynamic processes in the natural world, we must strip away layers and confounding variables that may mask the signal we hope to understand. In this case seahorse species, Hippocampus abdominalis, or the pot-bellied seahorse, made an unlikely but ideal study system. The first layer to strip away was neutral genetic variation within the population. A multilocus genetic …

The Genetic Basis Of Adaptation To Environmental Stress In Two Grass Genomic Model Systems, David Mitchell Goad

Arts & Sciences Electronic Theses and Dissertations

Plants are exposed to a wide variety of environmental stress in the wild and have developed an equally diverse set of adaptations to tolerate them. The evolutionary processes that have led to this functional diversification, and the specific genes and physiological mechanisms involved, are of immense interest to both evolutionary biologists and crop breeders. In this dissertation I investigate adaptation to different types of environmental stress in two economically important grass species, seashore paspalum (Paspalum vaginatum Sw.) and rice (Oryza sativa L.).

Seashore paspalum is a halophytic turfgrass that occupies habitats which can dramatically differ in salt concentration. Populations may …

Population Genetics Of A Reintroduced Fisher (Pekania Pennanti) Population In West Virginia, Caroline E. Harms

Graduate Theses, Dissertations, and Problem Reports

Fishers (Pekania pennanti) were reintroduced in West Virginia in 1969 with no population wide genetic analysis ever having been conducted. Genetic analysis of reintroduced populations is vital to assess genetic diversity as an indicative of population viability. My objective was to collect fisher samples throughout West Virginia, nearby states where fisher may be migrating (PA and NY), and the New Hampshire source population to provide a full genetic interpretation of the reintroduced West Virginia population. Genetic analysis was used to measure genetic diversity, admixture or delineation of subpopulations, and effective population size. Sample location and genetic data were …

Lepidopteran Granivory Reduces Seed Counts In A Rare Species Of Riparian Scour Prairies, Cheyenne Moore, Angela J. Mcdonnell, Scott Schuette, Christopher T. Martine

Faculty Journal Articles

In Pennsylvania Baptisia australis var. australis is found along only four waterways: the Allegheny River, Youghiogheny River, Clarion River, and Red Bank Creek. Because of its limited distribution and small number of extant populations, the species is considered state-threatened in Pennsylvania. In addition, the riparian prairie habitat that Pennsylvania Baptisia australis var. australis is restricted to is also in decline and considered vulnerable. Because of these conservation concerns, insights into the natural history of the taxon in the state is valuable and will inform conservation efforts. Field surveys and fruit collections along the Allegheny River and herbarium collections were used …

Investigation Into The Genetic Provenance Of Three Rare Plants With East-West Disjunction Patterns In Pennsylvania., Scott Schuette, Christopher T. Martine

Other Faculty Research and Publications

Rare plant conservation relies on an understanding of the natural history, biology and ecology, and real and potential threats to their populations to inform state regulations that serve to protect the species from extirpation. This work often involves extensive field surveys over several years to determine population sizes and whether those populations are seeing reductions in number of individuals necessary to maintain the genetic diversity within and between those populations. Species and populations with high genetic diversity are better equipped to withstand sudden changes to their habitats that derive from land use changes and changing climate. There are a variety …

Haplotype Network Branch Diversity, A New Metric Combining Genetic And Topological Diversity To Compare The Complexity Of Haplotype Networks, Eric Garcia, Daniel Wright, Remy Gatkins, May B. Roberts, Hudson T. Pinheiro, Eva Salas, Jei-Ying Chen, Jacob R. Winnikoff, Giacomo Bernardi

Biological Sciences Faculty Publications

A common way of illustrating phylogeographic results is through the use of haplotype networks. While these networks help to visualize relationships between individuals, populations, and species, evolutionary studies often only quantitatively analyze genetic diversity among haplotypes and ignore other network properties. Here, we present a new metric, haplotype network branch diversity (HBd), as an easy way to quantifiably compare haplotype network complexity. Our metric builds off the logic of combining genetic and topological diversity to estimate complexity previously used by the published metric haplotype network diversity (HNd). However, unlike HNd which uses a combination of network …

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 …

Population Structure Of A Federally Endangered Plant (Astragalus Jaegerianus Munz, Fabaceae) With Limited Range Using Microsatellites, Sueann Neal

Electronic Theses, Projects, and Dissertations

Studies on population genetics examine the relationship and effects of population structure, migration, gene flow and demographic history, and are therefore important in the conservation of endangered species. Astragalus jaegerianus, a critically federally endangered species found in a geographically restricted range is investigated to determine population structure and genetic variation. Previous research on A. jaegerianus focused on DNA sequence data for cpDNA and nrDNA showed no variation. Further research on A. jaegerianus utilizing AFLP’s on the whole genome indicated substantial gene diversity and population structure consistent with geographically widespread species. AFLP research is a cost-effective process to identify levels …

Genome Skimming And Microsatellite Analysis Reveal Contrasting Patterns Of Genetic Diversity In A Rare Sandhill Endemic (Erysimum Teretifolium, Brassicaceae), José Carlos Del Valle, Julie A. Herman, Justen B. Whittall

Biology

Barriers between islands often inhibit gene flow creating patterns of isolation by distance. In island species, the majority of genetic diversity should be distributed among isolated populations. However, a self-incompatible mating system leads to higher genetic variation within populations and very little between-population subdivision. We examine these two contrasting predictions in Erysimum teretifolium, a rare self-incompatible plant endemic to island-like sandhill habitats in Santa Cruz County, California. We used genome skimming and nuclear microsatellites to assess the distribution of genetic diversity within and among eight of the 13 remaining populations. Phylogenetic analyses of the chloroplast genomes revealed a deep …

Population Genetics Of A Recent Range Expansion By The Southern Pine Beetle, Dendroctonus Frontalis, Into The Northeastern United States, Megan Stubbs

Honors Theses

Population genetics as a field of study aims to determine the genetic variation among individuals in a population, and differences among populations. Certain population genetic analyses can provide such information and be used to better understand the biological aspects to a species’ expansion beyond its native range. The southern pine beetle (SPB), Dendroctonus frontalis, has become an invasive pest to pine forests in northeastern United States with its recent range expansion. Nine microsatellite loci were first developed and then used in analyses. To determine what the genetic variation is among individuals in SPB populations across its entire range, including …

Population Structure And Reproductive Biology Of Monilinia Vaccinii-Corymbosi (Reade) Honey In Lowbush Blueberry In Maine, Katherine A. Ashley

Electronic Theses and Dissertations

Lowbush blueberry, Vaccinium angustifolium Aiton, is both an economically and culturally important crop in Maine, being one of the few endemic crops to North America. The fungus Monilinia vaccinii-corymbosi (Mvc) causes mummy berry disease and is a significant pathogen of both highbush (Vaccinium corymbosum) and lowbush blueberries. While impacts of this disease are not regularly documented, it is estimated that 30-50% of the yield in an unmanaged field can be lost because of Mvc. This disease is typically managed with fungicides or burning of the field during years when the field is pruned, however, the impacts to the …

Evolutionary Inference From Admixed Genomes: Implications Of Hybridization For Biodiversity Dynamics And Conservation, Tyler Chafin

Graduate Theses and Dissertations

Hybridization as a macroevolutionary mechanism has been historically underappreciated among vertebrate biologists. Yet, the advent and subsequent proliferation of next-generation sequencing methods has increasingly shown hybridization to be a pervasive agent influencing evolution in many branches of the Tree of Life (to include ancestral hominids). Despite this, the dynamics of hybridization with regards to speciation and extinction remain poorly understood. To this end, I here examine the role of hybridization in the context of historical divergence and contemporary decline of several threatened and endangered North American taxa, with the goal to illuminate implications of hybridization for promoting—or impeding—population persistence in …