Genetics and Genomics Commons^™

Adapting Population Genetics, Practice, And Policy For Plant Conservation In A Changing World, Cooper M. Kimball-Rhines

Graduate Doctoral Dissertations

Biodiversity conservation is an inherently interdisciplinary goal that requires effective collaboration among academics, ecosystem managers, policymakers, and other stakeholders. Codesigning research with these groups ensures experiments are useful and improves adoption of policy and practice recommendations while advancing our understanding of basic science. This dissertation explores the power of codesigned research in shaping plant conservation strategies using stakeholder engagement, causal inference, demographic modeling, and multi-omic sequencing techniques. In chapter 1 I discuss the history of New England ecosystems and the need for research-driven changes to plant conservation policy and practice in the face of global change. In chapter 2, I …

Dosage Sensitivity And The Evolution Of Dosage Compensation: Tests Of The Insensitive Sex Chromosome Hypothesis In Flour Beetles, Shana Pau

Biology Dissertations

Sex chromosome evolution generates imbalances in gene dosage that can disrupt gene expression and organismal function. These imbalances are often resolved through dosage compensation mechanisms, yet the factors that drive the emergence and diversity of these systems remain poorly understood. This dissertation addresses a central question in evolutionary genomics: what governs the evolution of dosage compensation?

Focusing on dosage sensitivity as a potential driver, I evaluate the Insensitive Sex Chromosome Hypothesis (ISCH), which predicts that chromosome-wide compensation is more likely to evolve in genomic contexts that are not depleted of dosage-sensitive genes. Using flour beetles (Tribolium spp.) as a …

Comparative Analysis Of Six New Chloroplast Genomes In Platanthera (Orchidaceae) Enhances Understanding Of Its Diversification, Lisa E. Wallace, Martin I. Batalla, Matthew Maisonave

Biological Sciences Faculty Publications

Platanthera is among the most diverse genera of orchids in north temperate regions, with high species diversity in Asia and North America. Despite many ecological studies in this group, little is known about its genomic diversity. Here, we report the newly annotated chloroplast genomes from six species in subgenus Limnorchis from North America and compare them with plastomes published for Platanthera species from Asia and Europe. We found that the plastomes of species in subg. Limnorchis are among the smallest reported for Platanthera thus far. While major structural differences were not detected in the newly sequenced species, ndh genes were …

Phylogeography, Fungal Host Specificity, And Fitness In The Corallorhiza Maculata Species Complex, Hana Thixton-Nolan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Mycoheterotrophic plants exploit fungi for most or all nutritional needs, providing a compelling system to address the evolutionary consequences of genome reduction, population-level variation, and germination requirements. I am using the widespread Corallorhiza maculata species complex to address questions of genomic variation, fungal host specificity, morphological variation, and germination requirements across the broad geographic range from Mexico to northern North America. This complex contains C. bulbosa, C. macrantha, and C. mertensiana, the latter with three varieties (maculata, occidentalis, and mexicana). These taxa vary in flowering time, floral morphology, and fungal associations. However, the degree …

Elucidating The Role Of Transposable Element Derived Gene, Dplg3, In Drosophila Melanogaster, Kaisy A. Martinez

2025 Spring Honors Capstone Projects - Archive

A big fraction of most eukaryotic genomes is comprised of transposable elements (TEs). TEs are mobile genetic sequences often causing deleterious effects as they increase in copy number. On rare occasions, TEs can undergo molecular domestication, where the TE proteins are co-opted by the host to serve cellular functions. In Drosophila melanogaster, domestication from PIF/Harbinger TEs has resulted in five Drosophila PIF-Like Genes (DPLG1-4 and 8). This study focuses on investigating the function of DPLG3. In DPLG3 knock out lines, DPLG3-KO, a fraction of the progeny shows an abnormal gonad phenotype. We sought to confirm …

Robust Sex Determination In The Caenorhabditis Nigoni Germ Line, Jonathan P Harbin, Yongquan Shen, Shin-Yi Lin, Kevin Kemper, Eric S Haag, Erich M Schwarz, Ronald E Ellis

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Sexual characteristics and reproductive systems are dynamic traits in many taxa, but the developmental modifications that allow change and innovation are largely unknown. A leading model for this process is the evolution of self-fertile hermaphrodites from male/female ancestors. However, these studies require direct analysis of sex-determination in male/female species, as well as in the hermaphroditic species that are related to them. In Caenorhabditis nematodes this has only become possible recently, with the discovery of new species. Here, we use gene editing to characterize major sex-determination genes in C. nigoni, a sister to the widely studied hermaphroditic species C. briggsae. These …

Karyotyping As A Method To Verify Phylogenetic Relationships Among The Enneacanthus Species, Ophelia A. Anderson

Theses and Dissertations

The Enneacanthus genus consists of three species of freshwater fish endemic to eastern North America: E. obesus (Banded Sunfish), E. gloriosus (Blue Spotted Sunfish), and E. chaetodon (Black Banded Sunfish). Previous studies using molecular data suggest that E. obesus and E. gloriosus are more closely related, with E. chaetodon as the most distantly related species in the genus. This study investigates the phylogenetic relationship among the Enneacanthus species, using karyotype characteristics - chromosome number, morphology and fundamental number - as comparative metrics. Chromosome spreads were obtained from scale and gill epithelium samples collected between 1993 and 1994. Prepared slides …

Rewiring The Sex-Determination Pathway During The Evolution Of Self-Fertility., Yongquan Shen, Shin-Yi Lin, Jonathan Harbin, Richa Amin, Allison Vassalotti, Joseph Romanowski, Emily Schmidt, Alexis Tierney, Ronald E Ellis

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Although evolution is driven by changes in how regulatory pathways control development, we know little about the molecular details underlying these transitions. The TRA-2 domain that mediates contact with TRA-1 is conserved in Caenorhabditis. By comparing the interaction of these proteins in two species, we identified a striking change in how sexual development is controlled. Identical mutations in this domain promote oogenesis in Caenorhabditis elegans but promote spermatogenesis in Caenorhabditis briggsae. Furthermore, the effects of these mutations involve the male-promoting gene fem-3 in C. elegans but are independent of fem-3 in C. briggsae. Finally, reciprocal mutations in these genes show …

Evolution And Adaptation To Temperature In Thermotogota, Anne Amelia Farrell

Dartmouth College Ph.D Dissertations

Life thrives across incredibly diverse environmental conditions, yet most organisms are restricted to growing within a narrow range around their optimum growth temperature (OGT). The evolutionary events leading to changes in OGT are poorly understood, and it is uncertain if specific genes are required to thrive at a particular temperature. The bacterial phylum Thermotogota is an excellent model for the evolution of OGT. It comprises mesophilic, thermophilic, and hyperthermophilic members that collectively grow between 20°C and 90°C.

In this work, I analyze the history of OGT in the Thermotogota phylum and show how horizontal gene transfer contributes to the evolution …

Examining Population Structure Of Cismontane And Desert Populations Of Zebra-Tailed Lizards (Callisaurus Draconoides) Using Mitochondrial And Nuclear Intron Dna., Lauren Nicole Morrison

Electronic Theses, Projects, and Dissertations

Callisaurus draconoides, also known as the Zebra-Tailed lizard, belongs to the family Phrynosomatidae family (Pianka, et al. 1972). C. draconoides is a widespread desert lizard found western North America. In California, this species can be found in the Mojave and Colorado Deserts. There are currently several populations that reside in the San Bernardino basin on the cismontane side of the Transverse and Peninsular ranges. These mountain ranges have the potential to have isolated the cismontane populations from their typical desert ranges. In addition, geological passes have the potential to serve as migration corridor between the Deserts and cismontane regions. The …

A Balancing Act: Microrna Mediated Insect-Bacterial Homeostasis And The Tsetse Fly, Mason Hubbard Lee

Graduate Theses, Dissertations, and Problem Reports (ETD)

Microbial symbioses are ubiquitous across all kingdoms of life with broad and diverse impacts on the evolution of species. The sum of all microbes living in, on, or otherwise in close association with a host form the microbiota. In some cases, the development of a stable microbial association seems to have been necessary for the specialization of diet, as can be observed in numerous insect species, especially wood-eating, sap-feeding, and blood-feeding organisms. For the medically and economically tsetse fly (family Glossinidae), the mutualistic bacteria Wigglesworthia glossinidia is required for proper reproduction and supplementation of nutrients that the fly does not …

The Evolution Of The Metazoan Circadian Molecular Mechanism And The Conservation Of Canonical Circadian Elements, Olivia Waldridge

Theses and Dissertations--Biology

The temporal organization of biological activities through circadian rhythms is pivotal for the survival of organisms. Significant progress has been made in understanding the molecular foundations of animal circadian clocks through the characterization of key components such as Clock, Bmal1/Cycle(Cyc), Period (Per), Timeless, and Cryptochrome (Cry) in several model organisms. To determine the universality of this conservation, we investigated the sequences of these genes and their paralogs across 46 animal species that encompass multiple phyla in the metazoan kingdom to resolve the relative timing of duplication and loss events that have diversified core clock components in the metazoan kingdom. Using …

Functional Investigation Of Shaggy, An Inhibitor Of Canonical Wnt Signaling, In The Tardigrade Hypsibius Exemplaris, Raul A. Chavarria

UNF Graduate Theses and Dissertations

Tardigrades have a highly simplified anteroposterior (AP) axis. The mechanisms that regulate the development of this secondarily simplified AP axis are not known. In many animals, the canonical Wnt (cWnt) signaling pathway regulates primary axis establishment through antagonistic interactions with inhibitors of cWnt signaling. This study investigated the roles of shaggy, an inhibitor of cWnt signaling, in regulating development in the tardigrade Hypsibius exemplaris. Gene expression patterns of shaggy and other components of the cWnt signaling pathway were analyzed alongside markers of anterior and posterior identity using Hybridization Chain Reaction in situ in H. exemplaris. RNA interference …

A Case Of Incipient Budding Speciation In The California Floristic Province, Infraspecific Divergence In Abronia Villosa, Eli J. Allen

Cal Poly Humboldt theses and projects

Physical barriers to gene flow are the traditional evidence for species divergence. Conversely, there has been increasing acknowledgment of speciation in the face of gene flow as an evolutionary process. Budding speciation involves peripheral populations adapting to local ecological conditions, thereby budding off from a widespread progenitor species. Budding speciation is distinguished by ecological divergence and is generally evidenced by asymmetrical range size and nested phylogenetic relationships of sister species. The narrow endemic Abronia villosa var. aurita is adapted to montane sandy washes adjacent to its widespread sister variety, the desert dwelling var. villosa. Here, I tested the hypothesis …

Identification Of Constrained Sequence Elements Across 239 Primate Genomes, Lukas F K Kuderna, Jacob C Ulirsch, Sabrina Rashid, Mohamed Ameen, Laksshman Sundaram, Glenn Hickey, Anthony J Cox, Hong Gao, Arvind Kumar, Francois Aguet, Matthew J Christmas, Hiram Clawson, Maximilian Haeussler, Mareike C Janiak, Martin Kuhlwilm, Joseph D Orkin, Thomas Bataillon, Shivakumara Manu, Alejandro Valenzuela, Juraj Bergman, Marjolaine Rouselle, Felipe Ennes Silva, Lidia Agueda, Julie Blanc, Marta Gut, Dorien De Vries, Ian Goodhead, R Alan Harris, Muthuswamy Raveendran, Axel Jensen, Idriss S Chuma, Julie E Horvath, Christina Hvilsom, David Juan, Peter Frandsen, Joshua G Schraiber, Fabiano R De Melo, Fabrício Bertuol, Hazel Byrne, Iracilda Sampaio, Izeni Farias, João Valsecchi, Malu Messias, Maria N F Da Silva, Mihir Trivedi, Rogerio Rossi, Tomas Hrbek, Nicole Andriaholinirina, Clément J Rabarivola, Alphonse Zaramody, Clifford J Jolly, Jane Phillips-Conroy, Gregory Wilkerson, Christian Abee, Joe H Simmons, Eduardo Fernandez-Duque, Sree Kanthaswamy, Fekadu Shiferaw, Dongdong Wu, Long Zhou, Yong Shao, Guojie Zhang, Julius D Keyyu, Sascha Knauf, Minh D Le, Esther Lizano, Stefan Merker, Arcadi Navarro, Tilo Nadler, Chiea Chuen Khor, Jessica Lee, Patrick Tan, Weng Khong Lim, Andrew C Kitchener, Dietmar Zinner, Ivo Gut, Amanda D Melin, Katerina Guschanski, Mikkel Heide Schierup, Robin M D Beck, Ioannis Karakikes, Kevin C Wang, Govindhaswamy Umapathy, Christian Roos, Jean P Boubli, Adam Siepel, Anshul Kundaje, Benedict Paten, Kerstin Lindblad-Toh, Jeffrey Rogers, Tomas Marques Bonet, Kyle Kai-How Farh

Faculty, Staff and Students Publications

Noncoding DNA is central to our understanding of human gene regulation and complex diseases1,2, and measuring the evolutionary sequence constraint can establish the functional relevance of putative regulatory elements in the human genome3–9. Identifying the genomic elements that have become constrained specifically in primates has been hampered by the faster evolution of noncoding DNA compared to protein-coding DNA10, the relatively short timescales separating primate species11, and the previously limited availability of whole-genome sequences12. Here we construct a whole-genome alignment of 239 species, representing nearly half of …

Life, The Genome And Everything, Susan M Rosenberg

Faculty, Staff and Students Publications

In this issue of the Journal of Bacteriology, N. J. Bonde, E. A. Wood, K. S. Myers, M. Place, J. L. Keck, and M. M. Cox (J Bacteriol 205:e00184-23, 2023, https://doi.org/10.1128/jb.00184-23) used an unbiased transposon-sequencing (Tn-seq) screen to identify proteins required for life when cells lose the RecG branched-DNA helicase (synthetic lethality). The proteins’ identities indicate pathways that prevent endogenous DNA damage, pathways that prevent its homology-directed repair (HDR) “strand-exchange” intermediates between sister chromosomes, and pathways that resolve those intermediates. All avoid intermediate pile-up, which blocks chromosome segregation, causing “death-by-recombination.” DNA damage is managed to regulate crucial but …

Spatial Structure Formation By The Post-Transcriptional Gene Regulator Rsme In Pseudomonas Fluorescens Pf0-1, Anton Evans

Electronic Theses and Dissertations

Microorganisms are often found in microbial communities we call biofilms. Organisms living in these crowded environments have significant evolutionary pressure to retain access to the resources necessary to sustain life. My research uses the bacterium Pseudomonas fluorescens Pf0-1 to study how organisms evolve strategies to solve this crowding problem as aging colonies repeatedly generate mutant patches. These mutants expand the reach of the colony resulting in decreased local density as they push themselves up to the resource rich surface. These spatial structures result from social interactions between the mutant and the parental cells mediated through extracellular secretions, resulting in the …

Phylogeography Of The Pacific Sardine, Sardinops Sagax, In The Northeastern Pacific, Ella Adams

Theses

The Pacific Sardine, (Sardinops sagax), is a small, coastal pelagic species in the family Clupeidae. Sardine are an ecologically important forage fish for many animals, including larger, economically and ecologically important fishes, and have historically supported an important commercial fishery. When the fishery declined in the 1940s, a massive effort in understanding population structure for the Pacific Sardine resulted in a wealth of literature. Initially, these studies agreed on a large panmictic population with high annual variation, but the general consensus has since been that there are multiple subpopulations of the Pacific Sardine along the West Coast of …

Illuminating The Drivers Of Genomic Diversification In Lamprologine Cichlids Of The Lower Congo River, Naoko P. Kurata

Dissertations, Theses, and Capstone Projects

Freshwater fishes are extraordinarily diverse, considering their available habitats represent a tiny proportion of the earth’s surface. Rivers connect heterogeneous habitats in a linear form and provide excellent simplified models to understand how aquatic biodiversity evolves. In particular, the lower Congo River (LCR) in west Central Africa consists of a dynamic hydroscape exhibiting extraordinary aquatic biodiversity, endemicity, and morphological and ecological specialization. This system is thus an excellent natural laboratory for understanding complex speciation and population diversification processes. In my research, I explore various drivers of diversification, and adaptive evolution in rheophilic lamprologine cichlids endemic to the LCR, including Lamprologus …

Past And Present Patterns Of Neutral And Adaptive Genetic Diversity In Wild Mandrills (Mandrillus Sphinx), Anna Weber

LSU New Orleans Theses and Dissertations

Although primates have fascinated researchers and the public alike for generations, one species that has remained enigmatic is the mandrill (Mandrillus sphinx), a large Cercopithecine monkey endemic to Central Africa. Mandrills are currently in decline due to bushmeat hunting, urbanization, and habitat loss. Neutral and adaptive genetic diversity are important tools for understanding evolutionary history and future viability, since diversity influences a species’ ability to adapt to a changing environment. However, thus far, minimal genetic information has been available for wild mandrills. Because of the dense vegetation in their tropical forest habitat, studying wild mandrills has proven to …

Impact Of The Dimethyl Sulfoxide Reductase Superfamily On The Evolution Of Biogeochemical Cycles, Michael Wells, Minjae Kim, Denise M. Akob, Partha Basu, John F. Stolz

UK CARES Faculty Publications

The dimethyl sulfoxide reductase (or MopB) family is a diverse assemblage of enzymes found throughout Bacteria and Archaea. Many of these enzymes are believed to have been present in the last universal common ancestor (LUCA) of all cellular lineages. However, gaps in knowledge remain about how MopB enzymes evolved and how this diversification of functions impacted global biogeochemical cycles through geologic time. In this study, we perform maximum likelihood phylogenetic analyses on manually curated comparative genomic and metagenomic data sets containing over 47,000 distinct MopB homologs. We demonstrate that these enzymes constitute a catalytically and mechanistically diverse superfamily defined not …

An Improved Germline Genome Assembly For The Sea Lamprey Petromyzon Marinus Illuminates The Evolution Of Germline-Specific Chromosomes, Nataliya Timoshevskaya, Kaan İ. Eşkut, Vladimir A. Timoshevskiy, Sofia M.C. Robb, Carson Holt, Jon E. Hess, Hugo J. Parker, Cindy F. Baker, Allison K. Miller, Cody Saraceno, Mark Yandell, Robb Krumlauf, Shawn R. Narum, Ralph T. Lampman, Neil J. Gemmell, Jacquelyn Mountcastle, Bettina Haase, Jennifer R. Balacco, Giulio Formenti, Sarah Pelan, Ying Sims, Kerstin Howe, Olivier Fedrigo, Erich D. Jarvis, Jeramiah James Smith

Markey Cancer Center Faculty Publications

Programmed DNA loss is a gene silencing mechanism that is employed by several vertebrate and nonvertebrate lineages, including all living jawless vertebrates and songbirds. Reconstructing the evolution of somatically eliminated (germline-specific) sequences in these species has proven challenging due to a high content of repeats and gene duplications in eliminated sequences and a corresponding lack of highly accurate and contiguous assemblies for these regions. Here, we present an improved assembly of the sea lamprey (Petromyzon marinus) genome that was generated using recently standardized methods that increase the contiguity and accuracy of vertebrate genome assemblies. This assembly resolves highly contiguous, somatically …

Natural Selection Of Immune And Metabolic Genes Associated With Health In Two Lowland Bolivian Populations, Amanda J. Lea, Angela Garcia, Jesusa Arevalo, Julien F. Ayroles, Kenneth Buetow, Steve W. Cole, Daniel Eid Rodriguez, Maguin Gutierrez, Heather M. Highland, Paul L. Hooper, Anne Justice, Thomas Kraft, Kari E. North, Jonathan Stieglitz, Hillard Kaplan, Benjamin C. Trumble, Michael Gurven

ESI Publications

A growing body of work has addressed human adaptations to diverse environments using genomic data, but few studies have connected putatively selected alleles to phenotypes, much less among underrepresented populations such as Amerindians. Studies of natural selection and genotype–phenotype relationships in underrepresented populations hold potential to uncover previously undescribed loci underlying evolutionarily and biomedically relevant traits. Here, we worked with the Tsimane and the Moseten, two Amerindian populations inhabiting the Bolivian lowlands. We focused most intensively on the Tsimane, because long-term anthropological work with this group has shown that they have a high burden of both macro and microparasites, as …

Development Of Graphical Models And Statistical Physics Motivated Approaches To Genomic Investigations, Yashwanth Lagisetty

Dissertations and Theses (Open Access)

Identifying genes involved in disease pathology has been a goal of genomic research since the early days of the field. However, as technology improves and the body of research grows, we are faced with more questions than answers. Among these is the pressing matter of our incomplete understanding of the genetic underpinnings of complex diseases. Many hypotheses offer explanations as to why direct and independent analyses of variants, as done in genome-wide association studies (GWAS), may not fully elucidate disease genetics. These range from pointing out flaws in statistical testing to invoking the complex dynamics of epigenetic processes. In the …

Plastic And Evolved Responses In The Eastern Oyster, Crassostrea Virginica, To Environmental Variation In The Northern Gulf Of Mexico, Kyle Sirovy

LSU Doctoral Dissertations

Climate change and other anthropogenic impacts are causing rapid alterations to many of the world’s most productive coastal ecosystems and there is an urgent need to understand how species will respond to these environmental changes. Organisms may respond through plasticity, evolution, or the evolution of plasticity. In this dissertation, I evaluate the role of plastic and evolved responses in the eastern oyster, Crassostrea virginica, to environmental variation in the northern Gulf of Mexico. I use comparative transcriptomics, physiology, and morphology to examine the relative contribution of plastic and evolved responses for oysters exposed to low salinity and outplant sites …

Assessing The Utility Of The Pmm And Mmc Indices Among Extant Hominoid Genera, Julie A. Strain

Theses and Dissertations

This thesis set out to incorporate extant hominoid genera into an analysis of PMM and MMC to assess utility in phylogeny and predicting known taxonomic groups. Based on previous claims, we expect PMM/pmm and MMC/mmc to perform better than M1/m1 shape and size, our baseline for success, but they do not.

Phylogenomic Discordance Suggests Polytomies Along The Backbone Of The Large Genus Solanum, Edeline Gagnon, Rebeccca Hilgenhof, Andrés Orejuela, Angela J. Mcdonnell, Gaurav Sablok, Xavier Aubriot, Leandro Giacomin, Yuri Gouvêa, Thamyris Bragionis, João Renato Stehmann, Lynn Bohs, Steven Dodsworth, Christopher T. Martine, Péter Poczai, Sandra Knapp, Tiina Särkinen

Faculty Journal Articles

Premise of the study

Evolutionary studies require solid phylogenetic frameworks, but increased volumes of phylogenomic data have revealed incongruent topologies among gene trees in many organisms both between and within genomes. Some of these incongruences indicate polytomies that may remain impossible to resolve. Here we investigate the degree of gene-tree discordance in Solanum, one of the largest flowering plant genera that includes the cultivated potato, tomato, and eggplant, as well as 24 minor crop plants.

Methods

A densely sampled species-level phylogeny of Solanum is built using unpublished and publicly available Sanger sequences comprising 60% of all accepted species (742 spp.) …

Why Sequence All Eukaryotes?, Mark Blaxter, John M. Archibald, Anna K. Childers, Jonathan A. Coddington, Keith A. Crandall, Federica Di Palma, Richard Durbin, Scott V. Edwards, Jennifer A.M. Graves, Kevin J. Hackett, Neil Hall, Erich D. Jarvis, Rebecca N. Johnson, Elinor K. Karlsson, W. John Kress, Shigehiro Kuraku, Mara K. N. Lawniczak, Kerstin Lindblad-Toh, Jose V. Lopez, Nancy A. Moran, Gene E. Robinson, Oliver A. Ryder, Beth Shapiro, Pamela S. Soltis, Tandy Warnow, Guojie Zhang, Harris A. Lewin

Biology Faculty Articles

Life on Earth has evolved from initial simplicity to the astounding complexity we experience today. Bacteria and archaea have largely excelled in metabolic diversification, but eukaryotes additionally display abundant morphological innovation. How have these innovations come about and what constraints are there on the origins of novelty and the continuing maintenance of biodiversity on Earth? The history of life and the code for the working parts of cells and systems are written in the genome. The Earth BioGenome Project has proposed that the genomes of all extant, named eukaryotes—about 2 million species—should be sequenced to high quality to produce a …

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 …

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 …