Genetics and Genomics Commons^™

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 …

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 …

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

College of Graduate Studies: Theses & 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

College of Graduate Studies: Theses & 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 …

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

College of Graduate Studies: Theses & 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 …

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, …

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 …

Climate-Assisted Persistence Of Tropical Fish Vagrants In Temperate Marine Ecosystems, Laura Gajdzik, Thomas M. Decarlo, Adam Koziol, Mahsa Mousavi-Derazmahalleh, Megan Coghlan, Matthew W. Power, Michael Bunce, David Fairclough, Michael J. Travers, Glenn I. Moore, Joseph D. Dibattista

Fisheries Research Articles

Rising temperatures and extreme climate events are propelling tropical species into temperate marine ecosystems, but not all species can persist. Here, we used the heatwave-driven expatriation of tropical Black Rabbitfish (Siganus fuscescens) to the temperate environments of Western Australia to assess the ecological and evolutionary mechanisms that may entail their persistence. Population genomic assays for this rabbitfish indicated little genetic differentiation between tropical residents and vagrants to temperate environments due to high migration rates, which were likely enhanced by the marine heatwave. DNA metabarcoding revealed a diverse diet for this species based on phytoplankton and algae, as well …

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 …

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

College of Graduate Studies: Theses & 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 …

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 …

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

Graduate Theses, Dissertations, and Problem Reports (ETD)

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 …

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 …

The Ecology And Evolutionary History Of Two Musk Turtles In The Southeastern United States, Grover Brown

Dissertations

Turtles are among one of the most imperiled vertebrate groups on the planet with more than half of all species worldwide listed as threatened, endangered or extinct by the International Union of the Conservation of Nature. The Southeastern United States is a global biodiversity hotspot for turtles, and it likely represents the last area on the planet of both high diversity and high abundance of turtle species. In the past century, there has been an exponential increase in the number of publications on turtles in the United States and Canada, however a recent review of the literature suggests that this …

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 …

A Basic Ddradseq Two‐Enzyme Protocol Performs Well With Herbarium And Silica‐Dried Tissues Across Four Genera, Ingrid E. Jordon-Thaden, James B. Beck, Catherine A. Rushworth, Michael D. Windham, Nicolas Diaz, Jason T. Cantley, Christopher T. Martine, Carl J. Rothfels

Faculty Journal Articles

Premise

The ability to sequence genome‐scale data from herbarium specimens would allow for the economical development of data sets with broad taxonomic and geographic sampling that would otherwise not be possible. Here, we evaluate the utility of a basic double‐digest restriction site–associated DNA sequencing (ddRADseq) protocol using DNAs from four genera extracted from both silica‐dried and herbarium tissue.

Methods

DNAs from Draba, Boechera, Solidago, and Ilex were processed with a ddRADseq protocol. The effects of DNA degradation, taxon, and specimen age were assessed.

Results

Although taxon, preservation method, and specimen age affected data recovery, large phylogenetically informative …

Snp Population Genetic Data For The Seagrass Halodule Uninervis From Pilbara Region, Western Australia, Kathryn Margaret Mcmahon, Richard Evans

Research Datasets

This dataset contains 80 SNP loci from 15 locations with 25-47 samples per locations. Each column contains data from two alleles. All genotyped samples are included. Prior to population genetic analysis clone mates were identified and removed.

De Novo Development And Characterization Of Tetranucleotide Microsatellite Loci Markers From A Southeastern Population Of The House Finch (Haemorhous Mexicanus), Edgar E. Sanchez, J Dylan Maddox, Douglas G. Barron

Journal of the Arkansas Academy of Science

Microsatellites are short tandem repeats (e.g. TAGATAGA) of base pairs in a species’ genome. High mutation rates in these regions produce variation in the number of repeats across individuals that can be utilized to study patterns of population- and landscape-level genetics and to determine parentage genetically. In this project our objective was to develop microsatellite markers for the House Finch, Haemorhous mexicanus. This species has become one of the most well-studied species of songbirds due to its unique geographical, evolutionary, and epidemiological history. Using mist-nets we captured birds on the Arkansas Tech University campus and collected blood samples to …

Harnessing Population Genetics For Pest Management: Theory And Application For Urban Rats, Matthew Combs, Kaylee Byers, Chelsea Himsworth, Jason Munshi-South

Human–Wildlife Interactions

Effective management of rodent pests requires an ecological understanding of how they move through their environment and how those movements influence the invasion, persistence, or reinvasion of problematic colonies. Traditional methodologies used to describe rodent movement patterns, such as mark-recapture, are hindered by their time-consuming nature and limited geographic scope. As such, our understanding of how rodents interact with urban environments remains limited. Population genetic principles and tools have the capacity to greatly increase our understanding of rodent population dynamics, ecological relationships, and movements across space, but this field is often unapproachable to non-scientist pest management professionals (PMPs). In this …

Spatial Genetic Structure And Local Adaptation Within And Among Foxtail Pine (Pinus Balfouriana Subsp. Balfouriana) Populations Located In The Klamath Mountains, California, Rebecca D. Piri

Theses and Dissertations

Foxtail pine (Pinus balfouriana) is a subalpine conifer endemic to California, notably separated into two disjunct subspecies. Previous studies have described the northern subspecies,Pinus balfouriana subsp. balfouriana,as having an uncommonly high level of genetic differentiation and no discernible spatial patterns in phenotypic variation. This study seeks to characterize the spatial genetic structure and patterns of selection of the northern subspecies (Pinus balfouriana subsp. balfouriana) using genome-wide data and to identify the influence of ecology and environment on the unique genetic patterns. I show that genetic differentiation among populations is much less than previously estimated …

Phylogeny And Population Genetic Analyses Reveals Cryptic Speciation In The Bombus Fervidus Species Complex (Hymenoptera: Apidae), Jonathan B. Koch, Juanita Rodriguez, James P. Pitts, James P. Strange

Ecology Center Publications

Bumble bees (Bombus Latrielle) are significant pollinators of flowering plants due to their large body size, abundant setae, and generalist foraging strategies. However, shared setal coloration patterns among closely and distantly related bumble bee species makes identification notoriously difficult. The advent of molecular genetic techniques has increased our understanding of bumble bee evolution and taxonomy, and enables effective conservation policy and management. Individuals belonging to the North American Bombus fervidus species-complex (SC) are homogenous in body structure but exhibit significant body color phenotype variation across their geographic distribution. Given the uncertainty of the genealogical boundaries within the SC, some …

Hominoid Intraspecific Cranial Variation Mirrors Neutral Genetic Diversity, Julia M. Zichello, Karen L. Baab, Kieran P. Mcnulty, Christopher J. Raxworthy, Michael E. Steiper

Publications and Research

Natural selection, developmental constraint, and plasticity have all been invoked as explanations for intraspecific cranial variation in humans and apes. However, global patterns of human cranial variation are congruent with patterns of genetic variation, demonstrating that population history has influenced cranial variation in humans. Here we show that this finding is not unique to Homo sapiens but is also broadly evident across extant ape species. Specifically, taxa that exhibit greater intraspecific cranial shape variation also exhibit greater genetic diversity at neutral autosomal loci. Thus, cranial shape variation within hominoid taxa reflects the population history of each species. Our results suggest …

Genotype Fingerprints Enable Fast And Private Comparison Of Genetic Testing Results For Research And Direct-To-Consumer Applications., Max Robinson, Gustavo Glusman

Articles, Abstracts, and Reports

Genetic testing has expanded out of the research laboratory into medical practice and the direct-to-consumer market. Rapid analysis of the resulting genotype data now has a significant impact. We present a method for summarizing personal genotypes as 'genotype fingerprints' that meets these needs. Genotype fingerprints can be derived from any single nucleotide polymorphism-based assay, and remain comparable as chip designs evolve to higher marker densities. We demonstrate that these fingerprints support distinguishing types of relationships among closely related individuals and closely related individuals from individuals from the same background population, as well as high-throughput identification of identical genotypes, individuals in …

Population Genetics And Bumble Bee Conservation: Saving Species By Thinking Small, Cady Greenslit

Lawrence University Honors Projects

Pollinators have experienced a severe decline over the last few decades, and this includes bumble bee populations (g. Bombus). Bumble bees are important native pollinators, and here I investigate the health of local populations with molecular tools. The field of conservation genetics has created useful methodology for investigating the health and informing management strategies of threatened populations. This work investigates and describes the applications of population genetics, which uses span across the board. These applications are then brought back into the context of bumble bee conservation, and how they fit into the experimental plan I originally designed. I designed …

The Evolutionary History Of Nebraska Deer Mice: Local Adaptation In The Face Of Strong Gene Flow, Susanne P Pfeifer, Stefan Laurent, Vitor C. Sousa, Catherine R. Linnen, Matthieu Foll, Laurent Excoffier, Hopi E. Hoekstra, Jeffrey D. Jensen

Biology Faculty Publications

The interplay of gene flow, genetic drift, and local selective pressure is a dynamic process that has been well studied from a theoretical perspective over the last century. Wright and Haldane laid the foundation for expectations under an island-continent model, demonstrating that an island-specific beneficial allele may be maintained locally if the selection coefficient is larger than the rate of migration of the ancestral allele from the continent. Subsequent extensions of this model have provided considerably more insight. Yet, connecting theoretical results with empirical data has proven challenging, owing to a lack of information on the relationship between genotype, phenotype, …

Dna Extraction And Microsatellite Amplification Of Daphnia Pulicaria Resting Eggs: Analysis Of Allele Frequencies Through Time, Anna Ries

Departmental Honors Projects

A paleoecological approach allows for the study of genetic change in populations over longer periods of time than would be possible if one were sampling populations from year to year. Daphnia and other cladoceran zooplankton are amenable to this type of study because they produce diapausing embryos (ephippial eggs) when they sexually reproduce, and these resting eggs can remain viable for decades to centuries in lake sediments. This study uses paleoecological methods as well as a new methodology for ephippial DNA extraction and amplification to assay for genetic variation in ephippial eggs obtained from sediments of varying ages from Square …