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Articles 1 - 30 of 103
Full-Text Articles in Genetics and Genomics
Investigating Cryptic Diversity In The Hawaiian Endemic Plant, Psychotria Mariniana (Rubiaceae), Uyen Thi Hoang Nguyen
Investigating Cryptic Diversity In The Hawaiian Endemic Plant, Psychotria Mariniana (Rubiaceae), Uyen Thi Hoang Nguyen
Master's Theses
Islands, with their isolation and steep environmental gradients, serve as natural laboratories for studying speciation. Molecular phylogenetic and population genetic methods utilizing Next-Generation Sequencing (NGS) have revolutionized our ability to document patterns of genetic divergence and diversity. Cryptic diversity, genetically distinct populations that were previously unrecognized as unique, and cryptic speciation, where divergent genetic populations may be deserving of status as unique species, have been observed in many taxa. The Hawaiian Islands provide an ideal setting for studying divergence and speciation due to their extreme isolation, known ages, and volcanic origin. Previous work has investigated the evolutionary relationships of the …
Population Structure And Connectivity Of Atlantic Nurse Sharks (Ginglymostoma Cirratum) In The Bahamas And Outlying Areas, Baylie A. Fadool
Population Structure And Connectivity Of Atlantic Nurse Sharks (Ginglymostoma Cirratum) In The Bahamas And Outlying Areas, Baylie A. Fadool
School of Natural Resources: Dissertations, Theses, and Student Research
Understanding animal ecosystem dynamics and behavior at the individual and population levels is essential for identifying life-history patterns and important areas for management and conservation. Marine fish species often face minimal geographic barriers to movement, but environmental (temperature, salinity, current) or intrinsic barriers (philopatry, site fidelity) can dictate gene flow. Atlantic nurse sharks (Ginglymostoma cirratum) are an International Union for Conservation of Nature (IUCN) listed ‘vulnerable’ species and present a unique opportunity to investigate patterns of population structure and connectivity in large-bodied sharks. They are benthic and display reproductive philopatry, with recent work suggesting they have the capacity …
An Assessment Of Disease Risks, Population Genetics, And Spatial Ecology Of Appalachian Cottontails (Sylvilagus Obscurus) And Snowshoe Hares (Lepus Americanus) In West Virginia, Usa, Madison Leigh Miller
An Assessment Of Disease Risks, Population Genetics, And Spatial Ecology Of Appalachian Cottontails (Sylvilagus Obscurus) And Snowshoe Hares (Lepus Americanus) In West Virginia, Usa, Madison Leigh Miller
Graduate Theses, Dissertations, and Problem Reports (ETD)
Snowshoe hares (Lepus americanus) occupy a large range across the United States and Canada. While snowshoe hare populations are generally considered stable in the interior of their range, populations along range edges are experiencing declines, possibly driven by climate-related factors such as seasonal coat color mismatch. West Virginia represents one of the southernmost extents of the species’ range, yet little is known about the population genetic status or population sizes of snowshoe hares in the state. Appalachian cottontails (Sylvilagus obscurus) are another lagomorph species found in West Virginia. This species experienced a historical decline and currently …
Rapid Urbanization Reduces Genetic Diversity And Increases Genetic Differentiation Of A Lynx Spider Oxyopes Sertatus In Central Taiwan, Ying-Yuan Lo, Chi Wei, Wan-Jyun Chen, Chung-Ping Lin
Rapid Urbanization Reduces Genetic Diversity And Increases Genetic Differentiation Of A Lynx Spider Oxyopes Sertatus In Central Taiwan, Ying-Yuan Lo, Chi Wei, Wan-Jyun Chen, Chung-Ping Lin
Biological Sciences Faculty Publications
Urbanization is a dominant force driving destructive and irreversible changes of natural habitats in modern times. While the effects of urbanization on community composition and phenotypic responses are well-documented, its influence on genetic diversity and population structure remains understudied, particularly for invertebrates in subtropical regions. This study tested the hypothesis that urbanization reduces genetic diversity and increases population differentiation in the lynx spider Oxyopes sertatus, a common foliage-dwelling spider in Taiwan. We sampled 245 individuals from 17 sites distributed along an urban-rural gradient and quantified urbanization intensity using land-use composition at both landscape (4 km²) and local (0.25 km²) …
From Morphology To Machine Learning And Genomics: Understanding Phenotypic Variation In Wild Ducks, Sara Gonzalez
From Morphology To Machine Learning And Genomics: Understanding Phenotypic Variation In Wild Ducks, Sara Gonzalez
Open Access Theses & Dissertations
Understanding the genetic underpinning and distribution of phenotypic variation within and between divergent groups is core towards shedding light into how populations diverge and adapt, as well as how hybridization breaks or builds on these scenarios; and thus, central to evolutionary biology. In wild organisms, however, quantifying and linking phenotypic traits to underlying genetic processes, like mutation, gene expression, epigenetics and allele interactions, remains challenging. This difficulty arises from the complex interplay between morphology, environment, and gene regulation, as well as the logistical barriers of collecting and standardizing large-scale data across individuals and populations. As a result, researchers are increasingly …
Effects Of Urbanization On The Population Genetics And Morphology Of The White-Footed Mouse (Peromyscus Leucopus) Across An Urban–Rural Gradient, Sydney A. Morton
Effects Of Urbanization On The Population Genetics And Morphology Of The White-Footed Mouse (Peromyscus Leucopus) Across An Urban–Rural Gradient, Sydney A. Morton
Master's Theses
Urbanization alters landscapes in ways that can reshape wildlife populations by changing habitat connectivity, resource availability, and selective pressures. To investigate how urbanization influences both genetic differentiation and morphology in small mammals, I examined Peromyscus leucopus (PELE) across an urban–rural gradient in northern Georgia. Using RADseq SNP data from PELE individuals across 13 sites, I quantified pairwise genetic differentiation (FST) and tested how various environmental variables, including impervious surface cover, human population density, and tree canopy cover, predict genetic differentiation after accounting for geographic distance. Genetic differentiation increased with geographic distance and, after controlling for isolation by …
Population Structure Analysis Of Four Basal Higher-Attines Using Bioinformatic Approaches, Gabriel Mcdanield
Population Structure Analysis Of Four Basal Higher-Attines Using Bioinformatic Approaches, Gabriel Mcdanield
Biology Theses
Metapopulations within the family Formicidae are unique among other animals due to the large colonies they build, and the mating strategies required to fertilize a specialized reproductive caste that will often produce young for the life of the colony. One group of ants, the fungus-gardeners (tribe Attini). The population structure of North American non-leafcutting, fungus-gardening ants has been understudied, especially in the southwest of the United States. Additionally, not much is known about their dispersal biology, so the dynamics of dispersal of these species and how they affect population structure is likewise not well known. To shed light on the …
Genomic Structure Among Populations Of A Regionally Rare Perennial Plant Indicates The Need For Reevaluation Of Management Units, Cheyenne Moore, Angela J. Mcdonnell, Scott Schuette, Christopher T. Martine
Genomic Structure Among Populations Of A Regionally Rare Perennial Plant Indicates The Need For Reevaluation Of Management Units, Cheyenne Moore, Angela J. Mcdonnell, Scott Schuette, Christopher T. Martine
Faculty Journal Articles
Conservation of rare species often relies on the delineation of management units and genomic tools can now be applied for this purpose. However, this is not as common on a local scale, where populations are often small and fragmented, despite the utility of informing conservation and management practice at the regional level. We use a genotyping by sequencing (GBS) approach to assess the perennial riparian plant species Baptisia australis (Fabaceae) in Pennsylvania, where the taxon is at the edge of its natural distribution and considered threatened. In this system, we investigate whether sampled subpopulations exhibit genetic structure. We find that …
Intraspecific Genetic Variation In Green Salamanders (Aneides Aeneus) At Bays Mountain Park, Brianna Drake
Intraspecific Genetic Variation In Green Salamanders (Aneides Aeneus) At Bays Mountain Park, Brianna Drake
Electronic Theses and Dissertations
Accurate taxonomy is crucial for conserving vulnerable cryptic species like the green salamander (Aneides aeneus) in the Southern Appalachian Mountains. Prior studies identified three distinct lineages within the A. aeneus complex: Northern Appalachians, Southern Appalachians, and Blue-Ridge Escarpment. One previously collected sample indicated green salamanders in northeast Tennessee fit within the Northern lineage. The present study uses molecular data of A. aeneus at Bays Mountain Park (BMP) in Kingsport, Tennessee, to determine where the BMP population fits within these lineages. It was hypothesized that individuals from BMP belong in the northern lineage. Tail tips were collected from thirty-four …
Variation In Thermal Tolerance Plasticity And The Costs Of Heat Exposure In The Estuarine Sea Hare, Phyllaplysia Taylori, Richelle L. Tanner, Rauri C. K. Bowie, Cynthia Y. Wang-Claypool, Jonathan H. Stillman
Variation In Thermal Tolerance Plasticity And The Costs Of Heat Exposure In The Estuarine Sea Hare, Phyllaplysia Taylori, Richelle L. Tanner, Rauri C. K. Bowie, Cynthia Y. Wang-Claypool, Jonathan H. Stillman
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Climate change is increasing average temperatures and the frequency and intensity of thermal extremes in coastal marine environments. Organisms in coastal marine habitats are accustomed to environmental fluctuations and possess physiological plasticity that may be advantageous in response to increased occurrence of extremes. To examine whether such plasticity is locally adapted to environmental conditions, we investigated the relationship between genetic diversity and thermal tolerance plasticity in 11 populations of the direct-developing intertidal sea hare, Phyllaplysia taylori, on the western coast of the United States. Using whole-organism metrics of muscle function and metabolic rate and a ddRADseq genomic approach, we …
Tricolored Bat (Perimyotis Subflavus) Population Genetic Structure In The Southeastern United States, Laura Henderson
Tricolored Bat (Perimyotis Subflavus) Population Genetic Structure In The Southeastern United States, Laura Henderson
Master's Theses
Tricolored bats (Perimyotis subflavus) have experienced substantial population losses from white-nose syndrome (WNS), a disease caused by the pathogenic fungus Pseudogymnoascus destructans (Pd) which infects hibernating bats. Determining population genetic structure helps assess genetic diversity and the impacts of wildlife threats to populations. Pre-WNS data shows weak-to-negligible structure and panmictic P. subflavus populations at core portions of their range. However, current genetic data from their southeastern U.S. range is lacking. I sought to determine whether recent genetic data help resolve genetic structure among southeastern populations and assess genetic differences at two stages of impact: post-WNS and …
A Tail Of Two Fishes: Exploring Population Structure In Two Species Of Fishes Across The Galápagos Islands, Hillary Quach
A Tail Of Two Fishes: Exploring Population Structure In Two Species Of Fishes Across The Galápagos Islands, Hillary Quach
Honors Undergraduate Theses
The Galápagos Islands, a UNESCO World Heritage Site and a biodiversity hotspot with high levels of endemism, is home to over 440 species of fishes. Marine conditions across the Archipelago are greatly influenced by ocean currents in the region. The Pacific Equatorial Undercurrent, South Equatorial Current, and the Humboldt Current deliver waters rich in nutrients across the three major regions within the Galápagos (central, north, and west). These conditions create a dynamic environment close to the equator, enabling diverse species to thrive in distinct parts of the Galápagos. Despite the rich biodiversity in the region and diverse oceanographic conditions, there …
Hidden Markov Model For Identifying Local Variants In Human Genomes Using Simulated Data, Scott Mccallum
Hidden Markov Model For Identifying Local Variants In Human Genomes Using Simulated Data, Scott Mccallum
Electronic Theses and Dissertations
Identifying adaptive mutations in genetic data is challenging due to the low frequency of occurrence of such events, and because signatures of selection are intertwined with the footprints of various other evolutionary forces that shape our genomes. Even when a larger region appears to be under selection, genomic sites that are linked to adaptive mutations have similar statistical signals, and thus can obfuscate the identification of the actual adaptive mutation. The new method described here uses a Hidden Markov Model that allows for classification of neutral, linked, and sweep (adaptive mutation) genomic sites. This model is general and can be …
Analyses Of Whole-Genome Sequences From 185 North American Thoroughbred Horses, Spanning 5 Generations, Ernie Bailey, Carrie J. Finno, Jonah N. Cullen, Ted Kalbfleisch, Jessica Lynn Petersen
Analyses Of Whole-Genome Sequences From 185 North American Thoroughbred Horses, Spanning 5 Generations, Ernie Bailey, Carrie J. Finno, Jonah N. Cullen, Ted Kalbfleisch, Jessica Lynn Petersen
Department of Animal Science: Faculty Publications
Whole genome sequences (WGS) of 185 North American Thoroughbred horses were compared to quantify the number and frequency of variants, diversity of mitotypes, and autosomal runs of homozygosity (ROH). Of the samples, 82 horses were born between 1965 and 1986 (Group 1); the remaining 103, selected to maximize pedigree diversity, were born between 2000 and 2020 (Group 2). Over 14.3 million autosomal variants were identified with 4.5–5.0 million found per horse. Mitochondrial sequences associated the North American Thoroughbreds with 9 of 17 clades previously identified among diverse breeds. Individual coefficients of inbreeding, estimated from ROH, averaged 0.266 (Group 1) and …
The Influence Of Environmental Change On Genetic Diversity Across Spatial And Taxonomic Scales, Connor M. French
The Influence Of Environmental Change On Genetic Diversity Across Spatial And Taxonomic Scales, Connor M. French
Dissertations, Theses, and Capstone Projects
The spatial distribution of genetic diversity is of interest to biodiversity scientists and conservationists and is a fundamental metric of biodiversity. Genetic diversity patterns across spatial and taxonomic scales contain information about population and assemblage dynamics that can convey their resilience to environmental change. Ectotherms are especially linked to their environments and may be especially sensitive to fluctuations in the environment over time. Herein, I investigate global and regional patterns of genetic diversity in two groups of ectotherms, insects and lizards, to understand the relationship between environmental change and genetic diversity, from populations to assemblages. Overall, my research aims to …
Population Genetic Diversity In Two Biological Systems, Alyson Emery
Population Genetic Diversity In Two Biological Systems, Alyson Emery
Electronic Theses and Dissertations
Population genetic analysis can be used to answer questions about population structure and composition in many biological systems. Recent improvements to sequencing technologies have made population genetic studies more accessible than ever before. Many of the same techniques can be applied to different biological systems, but some analyses may differ depending on how genetically divergent the populations in question are. Here, we describe two unique projects using next-generation genome sequencing, each looking at population structure at different levels of genetic divergence: the first involved determining interspecific population structure between two species of hybridizing field cricket using a novel sequencing method, …
Omani Camels From A Cultural And Genomics Perspective, Al Muatasim Al Zadjali
Omani Camels From A Cultural And Genomics Perspective, Al Muatasim Al Zadjali
Electronic Theses and Dissertations
The Dromedarian camel, Camelus dromedarius, is native to the Arabian Peninsula, including the Sultanate of Oman. These camels are used for food, milk, as well as show and racing competitions. Despite their economic and cultural importance research on camels in Oman is limited. The goal of this study was to examine their genomic variation, relationship with camels in other parts of the Arabian Peninsula, and to determine if selective breeding has led to the establishment of distinct breeds in Oman. Information was compiled from multiple sources to produce a comprehensive review on the breeding, management, economic and cultural use, …
Assessing The Utility Of Breast Cancer Polygenic Risk Scores And Association With Clinical Factors In A Population Of Breast Cancer Patients, John L. Slunecka
Assessing The Utility Of Breast Cancer Polygenic Risk Scores And Association With Clinical Factors In A Population Of Breast Cancer Patients, John L. Slunecka
Dissertations and Theses
INTRODUCTION: Breast cancer (BC) is the most common cancer among women and is classified as a complex disease. Advances in population genomics have led to the development of polygenic risk scores (PRSs) with the potential to enhance current risk models, but replication is often limited. OBJECTIVE: We sought to assess the predictive capabilities of two high-powered BC PRSs in a sample population selected for breast cancer. In addition, the capacity of the PRSs to predict clinical variables that could improve BC screening and treatments was explored. METHODS: Two published PRS algorithms (313 vs 3820) were used to score female subjects …
Determining Population Structure In Kentucky Parascaris Univalens Specimens, Constance Finnerty
Determining Population Structure In Kentucky Parascaris Univalens Specimens, Constance Finnerty
Theses and Dissertations--Veterinary Science
Parascaris univalens is a highly pathogenic nematode that affects the gastrointestinal system of young horses. When unaddressed, this parasite causes severe intestinal impactions and even death. Parascaris univalens is also found to have an emergence of anthelmintic resistances, causing a concern for horse owners. Despite its clinical significance, very little work has been done on Parascaris univalens to identify its population structure. This study aimed to determine the population structure of Parascaris univalens through Illumina next generation sequencing (NGS) on three hierarchical categorizations: within a horse, within an isolated herd, and within horses in the state of Kentucky. A total …
Go West: Population Genomics Reveals Unexpected Population Fluctuations And Little Gene Flow In Western Hemisphere Populations Of The Predatory Lady Beetle, Hippodamia Convergens, Arun Sethuraman, Schyler O. Nunziata, Angela Jones, John J. Obrycki, David W. Weisrock
Go West: Population Genomics Reveals Unexpected Population Fluctuations And Little Gene Flow In Western Hemisphere Populations Of The Predatory Lady Beetle, Hippodamia Convergens, Arun Sethuraman, Schyler O. Nunziata, Angela Jones, John J. Obrycki, David W. Weisrock
Entomology Faculty Publications
Hippodamia convergens—the convergent lady beetle, has been used extensively in aug- mentative biological control of aphids, thrips, and whiteflies across its native range in North America, and was introduced into South America in the 1950s. Overwintering H. convergens populations from its native western range in the United States are com- mercially collected and released across its current range in the eastern USA, with little knowledge of the effectiveness of its augmentative biological control. Here we use a novel ddRADseq-based SNP/haplotype discovery approach to estimate its range- wide population diversity, differentiation, and recent evolutionary history. Our results indicate (1) significant population …
Range-Wide Analysis Of The Genetic Diversity And Genetic Structure Of The Spotted Turtle (Clemmys Guttata), Madison S. Whitehurst
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, …
Characterization Of The Immunoglobulin Lambda Chain Across Diverse Human Populations., William Gibson
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
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 …
A Weakly Structured Stem For Human Origins In Africa, Aaron P Ragsdale, Timothy D Weaver, Elizabeth G Atkinson, Eileen G Hoal, Marlo Möller, Brenna M Henn, Simon Gravel
A Weakly Structured Stem For Human Origins In Africa, Aaron P Ragsdale, Timothy D Weaver, Elizabeth G Atkinson, Eileen G Hoal, Marlo Möller, Brenna M Henn, Simon Gravel
Faculty, Staff and Students Publications
Despite broad agreement that Homo sapiens originated in Africa, considerable uncertainty surrounds specific models of divergence and migration across the continent1. Progress is hampered by a shortage of fossil and genomic data, as well as variability in previous estimates of divergence times1. Here we seek to discriminate among such models by considering linkage disequilibrium and diversity-based statistics, optimized for rapid, complex demographic inference2. We infer detailed demographic models for populations across Africa, including eastern and western representatives, and newly sequenced whole genomes from 44 Nama (Khoe-San) individuals from southern Africa. We infer a reticulated …
Landscape Genetics Of The Gulf Coast Tick, Amblyomma Maculatum, Sara Simmons Benham
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 …
Low And Differential Polygenic Score Generalizability Among African Populations Due Largely To Genetic Diversity, Lerato Majara, Allan Kalungi, Nastassja Koen, Kristin Tsuo, Ying Wang, Rahul Gupta, Lethukuthula L Nkambule, Heather Zar, Dan J Stein, Eugene Kinyanda, Elizabeth G Atkinson, Alicia R Martin
Low And Differential Polygenic Score Generalizability Among African Populations Due Largely To Genetic Diversity, Lerato Majara, Allan Kalungi, Nastassja Koen, Kristin Tsuo, Ying Wang, Rahul Gupta, Lethukuthula L Nkambule, Heather Zar, Dan J Stein, Eugene Kinyanda, Elizabeth G Atkinson, Alicia R Martin
Faculty, Staff and Students Publications
African populations are vastly underrepresented in genetic studies but have the most genetic variation and face wide-ranging environmental exposures globally. Because systematic evaluations of genetic prediction had not yet been conducted in ancestries that span African diversity, we calculated polygenic risk scores (PRSs) in simulations across Africa and in empirical data from South Africa, Uganda, and the United Kingdom to better understand the generalizability of genetic studies. PRS accuracy improves with ancestry-matched discovery cohorts more than from ancestry-mismatched studies. Within ancestrally and ethnically diverse South African individuals, we find that PRS accuracy is low for all traits but varies across …
A Comparison Of Microsatellites And Single Nucleotide Polymorphisms For The Assessment Of Population Structure In The Amblyomma Maculatum Koch, 1844 Species Complex, Henrey A. Deese
Electronic Theses and Dissertations
The Gulf Coast tick, Amblyomma maculatum Koch, 1844 is widespread throughout North and Central America and is the primary vector for the emerging pathogen Rickettsia parkeri. In the U.S., the population in the Southwest (A. maculatum morphotype III) is morphologically different from the population east of the Rocky Mountains (A. maculatum morphotype II). This research tests the hypothesis that A. maculatum morphotype II and morphotype III represent distinct species through the analysis and comparison of 6 microsatellite loci and suite of 135,221 Single nucleotide polymorphisms (SNPs) generated from ddRADseq. Population genetic analysis of both microsatellites and SNPs …
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
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
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 …
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 …