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Articles 61 - 90 of 319

Full-Text Articles in Evolution

The Effect Of Db1976 On The Fibrotic Response In Three-Spined Stickleback (Gasterosteus Aculeatus), Saif Quraishi Dec 2023

The Effect Of Db1976 On The Fibrotic Response In Three-Spined Stickleback (Gasterosteus Aculeatus), Saif Quraishi

Honors Scholar Theses

The study of fibrosis in stickleback has been a growing field in which there have been a few studies conducted. This study examines two experiments involving the inhibition of fibrosis in stickleback. The first experiment used fish from the Kenai River Flats (KRF) in Alaska. The second experiment used fish from Roselle Lake in British Columbia, Canada. To determine the impact the drug had on fibrosis, sticklebacks from the KRF population were treated with DB1976 as well as alum, a pro‐inflammatory vaccine adjuvant that causes fibrosis (Kool et. al 2012). When each DB1976 + alum treatment group was compared with …


Brown Anole (Anolis Sagrei) Hoxa5: Insights Into The Divergence Of Hoxa5 Gene Expression And Regulation Across Evolutionarily Divergent Gnathostome Vertebrates, Jennifer A. Lange, Amber L. Rittgers, Adam Davis Nov 2023

Brown Anole (Anolis Sagrei) Hoxa5: Insights Into The Divergence Of Hoxa5 Gene Expression And Regulation Across Evolutionarily Divergent Gnathostome Vertebrates, Jennifer A. Lange, Amber L. Rittgers, Adam Davis

Georgia Journal of Science

Hox genes are evolutionarily conserved developmental regulatory genes that function, in part, to pattern the anterior-posterior (AP) axis of organs and organ systems during animal embryonic development. Hoxa5, specifically, is shown to be expressed in the spinal cord, somites, or transient compartments giving rise to the vertebrae and ribs, developing gut, lungs, and limbs of the mouse (Mus musculus). The cis-regulatory elements (CREs), or short DNA sequences, that direct Hoxa5 expression in these embryonic domains have been mapped and functionally tested in the mouse as well. Similar Hoxa5 expression patterns have been observed in chicken ( …


Tracing Evolution Of Gene Transfer Agents Using Comparative Genomics, Roman Kogay Nov 2023

Tracing Evolution Of Gene Transfer Agents Using Comparative Genomics, Roman Kogay

Dartmouth College Ph.D Dissertations

The accumulating evidence suggest that viruses and their components can be domesticated by their hosts, equipping them with convenient molecular toolkits for various functions. One of such domesticated system is Gene Transfer Agents (GTAs) that are produced by some bacteria and archaea. GTAs morphologically resemble small phage-like particles and contain random fragments of their host genome. They are produced only by a small fraction of the microbial population and are released through a lysis of the host cell. Bioinformatic analyses suggest that GTAs are especially abundant in the taxonomic class of Alphaproteobacteria, where they are vertically inherited and evolve …


Book Review: Habitantes De La Obscuridad (Fauna Ibero-Balear De Las Cuevas) – Inhabitants Of The Darkness (Ibero-Baleric Fauna Of Caves), Oana Teodora Moldovan Oct 2023

Book Review: Habitantes De La Obscuridad (Fauna Ibero-Balear De Las Cuevas) – Inhabitants Of The Darkness (Ibero-Baleric Fauna Of Caves), Oana Teodora Moldovan

International Journal of Speleology

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Population Genomics, Ecology And Conservation Of Asterias Sea Stars In The North Atlantic, Melenia I. Giakoumis Sep 2023

Population Genomics, Ecology And Conservation Of Asterias Sea Stars In The North Atlantic, Melenia I. Giakoumis

Dissertations, Theses, and Capstone Projects

Uncovering how species respond to environmental change is a central question in biology (Ehrlén & Morris 2015; Habibullah et al. 2022). It is the key to elucidating the past, understanding the present and predicting the future of species’ population dynamics. This dissertation investigates the influence of environmental change on intertidal species’ distributions and genomics at several timescales, with implications for conservation.

Environmental changes have occurred throughout history, on a geological scale, and have shaped the global patterns of species’ distributions and population sizes. Biologists have long studied how geological history has shaped species distributions (Sanmartín 2012) in both terrestrial (Liu …


Sequestered Sequences: A Bioinformatic Approach To The Forgotten Genome, Dylan Barth Aug 2023

Sequestered Sequences: A Bioinformatic Approach To The Forgotten Genome, Dylan Barth

UNLV Theses, Dissertations, Professional Papers, and Capstones

As high throughput sequencing generates ever increasing amounts of genetic and epigenetic data new lines of inquiry open up in the field of genomic research. In this thesis, we discuss three ways in which we can utilize public databases of next generation genomic data in order to study areas of the genome previously ignored by traditional approaches. These include the study of linker regions between domains of proteins, indirect enhancers that do not strongly contact promoters of genes they regulate, and transposon-derived enhancer elements. The work uncovers many exceptions to known biological principles, and adds nuance to our understanding of …


Mitogenomes Revealed The History Of Bison Colonization Of Northern Plains After The Last Glacial Maximum, Igor V. Ovtchinnikov, Blake Mccann Jul 2023

Mitogenomes Revealed The History Of Bison Colonization Of Northern Plains After The Last Glacial Maximum, Igor V. Ovtchinnikov, Blake Mccann

Biology Faculty Publications

American bison demonstrated differential patterns of extinction, survival, and expansion since the terminal Pleistocene. We determined population dynamics of the Northern Great Plains bison using 40 mitochondrial genomes from radiocarbon dated remains with the age ranging from 12,226 to 167 calibrated years before present. Population dynamics correlated with environmental and anthropogenic factors and was characterized by three primary periods: terminal Pleistocene population growth starting 14,000 years ago, mid Holocene demographic stability between 6700 and 2700 years ago, and late Holocene population decline in the last 2700 years. Most diversification of mtDNA haplotypes occurred in the early Holocene when bison colonized …


Characterization Of Antimicrobial Properties Of Excrement And Functional Microbiome Of Black Vultures (Coragyps Atratus), Bridgette Gray Jul 2023

Characterization Of Antimicrobial Properties Of Excrement And Functional Microbiome Of Black Vultures (Coragyps Atratus), Bridgette Gray

Theses

Black vultures, Coragyps atratus, are obligate scavenging birds that consume and dispose of decaying carcasses and carrion. They fulfill a key ecological niche in the environments in which they live. It has been observed that these vultures sometimes excrete bodily waste onto their legs. This adaptive behavior could help aid them in controlling bacteria and other microbes they encounter while stepping into a carcass to eat. This study directly examined the antimicrobial properties of the excrement of black vultures across various bacterial species utilizing a zone of inhibition test and a nematode species utilizing a survival assay. The black vulture …


Ethical Issues And Standards Of Responsible Research Conduct And Monitoring In An Adventist Institution Of Higher Learning - The Babcock Experience, Kayode O. Ogunwenmo, Godswill N. Anyasor, Grace O. Tayo May 2023

Ethical Issues And Standards Of Responsible Research Conduct And Monitoring In An Adventist Institution Of Higher Learning - The Babcock Experience, Kayode O. Ogunwenmo, Godswill N. Anyasor, Grace O. Tayo

Adventist Human-Subject Researchers Association

Ethical issues and standards of responsible research conduct involving human participants are important considerations in any institution of higher learning and in particular Adventist institutions. Research conduct and ethics are reviewed and approved before they begin by the Babcock University Health Research Ethics Committee (BUHREC)


Acetate Metabolism In The Fungal Pathogen Cryptococcus Neoformans, Oly Ahmed May 2023

Acetate Metabolism In The Fungal Pathogen Cryptococcus Neoformans, Oly Ahmed

All Dissertations

Cryptococcus neoformans is an environmental basidiomycetous fungus with a worldwide distribution and a wide range of habitats. Inhalation of the desiccated yeasts or spores of C. neoformans often leads to opportunistic pulmonary infections in immunocompromised individuals, and in severe cases causes lethal meningitis following hematogenous dissemination. During infection, depending on the tissue and disease state, the invading fungi experience a range of nutrient microenvironments within the host body. As a result, rapid metabolic adaptations geared towards efficient utilization of carbon sources alternative to glucose become one of the prime determinants of survival and growth for the pathogen. Incidentally, cryptococcal infection …


Past And Present Patterns Of Neutral And Adaptive Genetic Diversity In Wild Mandrills (Mandrillus Sphinx), Anna Weber May 2023

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 …


Anomalies In The Mitochondrial Genomes Of Members Of Aliciidae, Boloceroididae, And Gonactiniidae (Actiniaria:Metridioidea), Isabel Pen Apr 2023

Anomalies In The Mitochondrial Genomes Of Members Of Aliciidae, Boloceroididae, And Gonactiniidae (Actiniaria:Metridioidea), Isabel Pen

2023 Midwest Ecology & Evolution Conference

Analysis of gene sequences from three mitochondrial and two nuclear genes for a broad sampling of actiniarian taxa proposed a novel grouping of the families Aliciidae, Boloceroididae, and Gonactiniidae. (Rodríguez et al., 2014). Although previously unlinked, the association of these taxa was credible given the consistency of the genetic data and the shared occurrence of anatomical traits, including complex column structures (Aliciidae and Boloceroididae), tentacular sphincters (Boloceroididae and Gonactiniidae), and retention of juvenile musculature in adults (Boloceroididae and Gonactiniidae). Although the mitochondrial genome structure of actiniarians is generally conserved, complete mitochondrial genomes identify unusual gene orders (Alicia sansibarensis: …


Qtl Analysis Of Body Size And Development Time In Dendroctonus Ponderosae, Camille M. Pushman Apr 2023

Qtl Analysis Of Body Size And Development Time In Dendroctonus Ponderosae, Camille M. Pushman

2023 Midwest Ecology & Evolution Conference

The mountain pine beetle (MPB, Dendroctonus ponderosae) is a pest species found in western Norh America that attacks and kills Pinus host trees. Previous studies have identified genetic divergence between populations and variation in life-history traits (body size and development time) that are likely important in local adaptation. To understand the underlying genetic architecture of MPB adaptation and divergence, we performed an F1 intercross between two distinct populations (Utah & Arizona) and performed a QTL analysis. We analyzed double digest RAD sequencing data from 181 F2 individuals. Our final dataset consists of 986 SNPs and we were able to …


Convergent Evolution Of Antifreeze Proteins In Two Insect Families Supported By Whole Genome And Gene Family Loci Analyses, Shaw Kagawa Apr 2023

Convergent Evolution Of Antifreeze Proteins In Two Insect Families Supported By Whole Genome And Gene Family Loci Analyses, Shaw Kagawa

2023 Midwest Ecology & Evolution Conference

Various Coleoptera (beetles) and Lepidoptera (moths) insects are known to produce highly active antifreeze peptides (AFPs), an adaptive trait that enabled them to avoid freezing and survive severe winters. These include the grain pest Tenebrio molitor (yellow mealworm), pine-boring Rhagium beetles, the fire-colored Dendroides beetles, a stag beetle, and the Choristoneura spruce budworms (moths). Insect AFPs are small peptides of ~8 to 15 kDa, consisting of several tandem 13-amino acid repeats of similar sequences, each ending with a conserved tripeptide Thr-Cys/aa-Thr motif, found to be important for ice binding. Except for the eastern spruce budworm, the evolutionary origin/s and process/es …


Genomic Basis Of Antifreeze Trait Divergence In Antarctic And Patagonian Toothfish, Shriram Bhat Apr 2023

Genomic Basis Of Antifreeze Trait Divergence In Antarctic And Patagonian Toothfish, Shriram Bhat

2023 Midwest Ecology & Evolution Conference

The Dissostichus genus of notothenioid fish contains two giant, iconic sister species, Dissostichus mawsoni (Antarctic toothfish) and Dissostichus eleginoides (Patagonian toothfish), which inhabit thermally distinct environments. D. mawsoni is protected by antifreeze glycoproteins (AFGPs) from freezing in the cold waters of the Southern Ocean, while D. eleginoides lacks detectable antifreeze activity despite its recent divergence. Interestingly, recent evidence suggests the possibility of a third species in the Dissostichus genus, which is currently believed to be a separate population of D. eleginoides closer to the Southern Ocean whose genome has recently been published. Our study focuses on D. eleginoides specimens from …


Geographic Analysis Of Sex Chromosome Polymorphism In The Virginian Wild Strawberry, Trezalka A. Budinsky Apr 2023

Geographic Analysis Of Sex Chromosome Polymorphism In The Virginian Wild Strawberry, Trezalka A. Budinsky

2023 Midwest Ecology & Evolution Conference

The evolution of sex chromosomes is a ubiquitous and essential diversifying mechanism in eukaryotes. Yet early stages of sex-chromosome differentiation are poorly understood. The subdioecious octoploid, Fragaria virginiana, provides a rare opportunity to study the beginnings of sex chromosome evolution due to its young, polymorphic ZW sex system. Females are ZW and males/hermaphrodites are ZZ. F. virginiana has a small sex-determining region (SDR) located on the female W chromosome that has undergone three transposition events between the strawberry's four subgenomes, resulting in three SDR haplotypes: alpha (the result of a first transposition and closest to a pre-sex chromosome ancestral …


Potential Loss Of Pheromone Receptors In The Red Milkweed Beetle, Tetraopes Tetrophthalmus (Coleoptera: Cerambycidae), Mathew A. Price Apr 2023

Potential Loss Of Pheromone Receptors In The Red Milkweed Beetle, Tetraopes Tetrophthalmus (Coleoptera: Cerambycidae), Mathew A. Price

2023 Midwest Ecology & Evolution Conference

The family of longhorn beetles (Coleoptera: Cerambycidae) are characterized by their elongate antennae, which are well adapted for detecting volatile compounds. This makes them an ideal family to study odorant receptor genes (ORs), which are the rapidly evolving family of proteins that are used by insects to detect odors at the molecular level. Here, we present data on 48 ORs we have sequenced and annotated from an antennal transcriptome of a male red milkweed beetle, Tetraopes tetrophthalmus. In contrast to most cerambycids, T. tetrophthalmus is not known to produce long-range sex pheromones to attract or select mates; correspondingly, …


Standing Genetic Variation As A Potential Mechanism Of Novel Cave Phenotype Evolution In The Freshwater Isopod, Asellus Aquaticus, Lizet R. Rodas, Serban M. Sarbu, Raluca Bancila, Devon Price, Žiga Fišer, Meredith E. Protas Feb 2023

Standing Genetic Variation As A Potential Mechanism Of Novel Cave Phenotype Evolution In The Freshwater Isopod, Asellus Aquaticus, Lizet R. Rodas, Serban M. Sarbu, Raluca Bancila, Devon Price, Žiga Fišer, Meredith E. Protas

Natural Sciences and Mathematics | Faculty Scholarship

Novel phenotypes can come about through a variety of mechanisms including standing genetic variation from a founding population. Cave animals are an excellent system in which to study the evolution of novel phenotypes such as loss of pigmentation and eyes. Asellus aquaticus is a freshwater isopod crustacean found in Europe and has both a surface and a cave ecomorph which vary in multiple phenotypic traits. An orange eye phenotype was previously revealed by F2 crosses and backcrosses to the cave parent within two examined Slovenian cave populations. Complete loss of pigmentation, both in eye and body, is epistatic to the …


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 Jan 2023

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 …


The Evolutionary Causes And Consequences Of Mammalian Hybridization, Kelsie E. Hunnicutt Jan 2023

The Evolutionary Causes And Consequences Of Mammalian Hybridization, Kelsie E. Hunnicutt

Electronic Theses and Dissertations

The natural recombination of divergent genomes within hybrid offspring provides windows through which we can study evolutionary processes and the dynamics of speciation. In this work, I use a combination of comparative and population genomics on both laboratory crosses of divergent rodent lineages and a hybrid zone of cottontail rabbits in the wild to study the causes and consequences of hybridization in mammals. Hybrid sterility is a common reproductive barrier between species that tends to preferentially manifest in the heterogametic sex and frequently genetically maps to the sex chromosomes. Thus, the sex chromosomes appear to play a special role in …


Molecular And Systemic Epigenetic Inheritance: Integrating Development, Genetics, And Evolution, Robert Lickliter, David S. Moore Jan 2023

Molecular And Systemic Epigenetic Inheritance: Integrating Development, Genetics, And Evolution, Robert Lickliter, David S. Moore

Pitzer Faculty Publications and Research

Currently, a central problem for theoretical biology is the integration of development with genetics and evolutionary theory. Through the late 20th century, biologists held that animals resemble their ancestors strictly because of the transgenerational transmission of DNA. This view effectively wrote development out of evolutionary biology. However, many molecular and developmental biologists now understand that phenotypes—anatomical, physiological, and behavioral traits—are not determined by genes (i.e., DNA segments) alone; instead, they emerge epigenetically from developmental processes involving co-acting genetic factors, environmental factors, molecular epigenetic factors, and other non-genetic factors within organisms’ bodies. This insight forces a rethinking of biological inheritance. …


Nuclear Phylogeny And Insights Into Whole-Genome Duplications And Reproductive Development Of Solanaceae Plants, Jie Wang, Weibin Xu, Junwen Zhai, Yi Hu, Jing Guo, Caifei Zhang, Yiyong Zhao, Lin Zhang, Christopher T. Martine, Hong Ma, Chien-Hsun Huang Jan 2023

Nuclear Phylogeny And Insights Into Whole-Genome Duplications And Reproductive Development Of Solanaceae Plants, Jie Wang, Weibin Xu, Junwen Zhai, Yi Hu, Jing Guo, Caifei Zhang, Yiyong Zhao, Lin Zhang, Christopher T. Martine, Hong Ma, Chien-Hsun Huang

Faculty Journal Articles

Solanaceae, the nightshade family, have ∼2700 species, including the important crops potato and tomato, ornamentals, and medicinal plants. Several sequenced Solanaceae genomes show evidence for whole-genome duplication (WGD), providing an excellent opportunity to investigate WGD and its impacts. Here, we generated 93 transcriptomes/genomes and combined them with 87 public datasets, for a total of 180 Solanaceae species representing all four subfamilies and 14 of 15 tribes. Nearly 1700 nuclear genes from these transcriptomic/genomic datasets were used to reconstruct a highly resolved Solanaceae phylogenetic tree with six major clades. The Solanaceae tree supports four previously recognized subfamilies (Goetzeioideae, Cestroideae, Nicotianoideae, …


Placing The Evolutionary History Of Desmognathus Salamanders In Context: A Phylogeographic Approach, Kara Jones Jan 2023

Placing The Evolutionary History Of Desmognathus Salamanders In Context: A Phylogeographic Approach, Kara Jones

Theses and Dissertations--Biology

Patterns of genetic variation do not arise in a vacuum but are instead shaped by the interplay between evolutionary forces and ecological constraints. Here, I use a phylogeographic approach to examine the role that ecology played in lineage divergence in the Desmognathus quadramaculatus species complex (Family: Plethodontidae), which consists of three nominal species: D. quadramaculatus, D. marmoratus, and D. folkertsi. Previous phylogenetic studies have shown that individuals from these species do not form clades based on phenotype. My approach to reconciling phylogenetic discordance was two-fold, using (1) genome-wide markers to provide insight into the …


Genetic And Environmental Contributions To Wolbachia-Induced Cytoplasmic Incompatibility, Kelley Van Vaerenberghe Jan 2023

Genetic And Environmental Contributions To Wolbachia-Induced Cytoplasmic Incompatibility, Kelley Van Vaerenberghe

Graduate Student Theses, Dissertations, & Professional Papers

Maternally-transmitted Wolbachia infect the cells of most insect species, but their frequencies in host populations vary. While much of their success can be attributed to their ability to manipulate host reproduction, these manipulations are context-dependent, varying due to several biotic and abiotic factors. Wolbachia’s most common manipulation, cytoplasmic incompatibility (CI), is a conditional sterility phenotype where male-female host compatibility depends on their infection status. Specifically, CI occurs when infected males produce modified sperm that cause increased embryonic lethality unless the female carries a similar infection. Rescuing their eggs from CI increases the relative fitness of infected females, promoting Wolbachia spread …


Effects Of Riverine Barriers On Avian Evolution In The Amazon Basin, Andre Eugene Moncrieff Dec 2022

Effects Of Riverine Barriers On Avian Evolution In The Amazon Basin, Andre Eugene Moncrieff

LSU Doctoral Dissertations

The high biodiversity found in the Amazon Basin has long captivated the attention of naturalists and evolutionary biologists seeking to explain its origins. Early observations by Alfred Wallace highlighted the role of rivers in delimiting the geographic ranges of many species; furthermore, where rivers narrow towards their headwaters, he noted that some species cross rivers freely. A major goal of this dissertation is to investigate how these and other observations about riverine barriers might inform our understanding of how speciation unfolds in Amazonia. My approach involved generating genomic data with dense geographic sampling for manakins in the genus Lepidothrix, …


Caribbean Reef-Building Coral-Symbiodiniaceae Network: Identifying Symbioses Critical For System Stability In A Changing Climate, Shaman Patel Dec 2022

Caribbean Reef-Building Coral-Symbiodiniaceae Network: Identifying Symbioses Critical For System Stability In A Changing Climate, Shaman Patel

All HCAS Student Capstones, Theses, and Dissertations

Increasing global ocean temperatures and frequency of marine heatwaves pose dire consequences for coral reefs. High temperatures often lead to disruptions in coral symbiosis resulting in coral bleaching, increasing the mortality of corals. However, corals can potentially avoid bleaching peril by associating with thermally tolerant symbionts. Here we provide a tool for understanding symbiosis network stability of Caribbean reef-building corals. We created a network of Caribbean hermatypic corals and their associated Symbiodiniaceae phylotypes. A bleaching model was applied to this network to test for resilience and robustness (R50) to thermal stress. It was also layered with trait data for coral …


Alu Dimorphism At The Pv92 Locus Of Chromosome 16 Is In Equilibrium For University Student Population, James M. Brooks, Mackenzie L. Thackston Oct 2022

Alu Dimorphism At The Pv92 Locus Of Chromosome 16 Is In Equilibrium For University Student Population, James M. Brooks, Mackenzie L. Thackston

Journal of the South Carolina Academy of Science

Alu is a retrotransposable element, which refers to its ability to be copied and move from one region of DNA to another DNA region. At the PV92 locus of chromosome 16, Alu is a 300 bp dimorphic insert that can either be present or absent. It does not encode a protein product and has lost the ability to transpose. It is specific to humans, and differences in genotype and allele frequencies between human populations are important tools in understanding evolution. In this research, data was obtained and analyzed from 269 students at Charleston Southern University (CSU) belonging to four different …


Chromosome Number Evolution, Phylogeography, And The Effects Of Climate Change On Species Distributions In Polyploid Plant Systems, Courtney H. Babin Aug 2022

Chromosome Number Evolution, Phylogeography, And The Effects Of Climate Change On Species Distributions In Polyploid Plant Systems, Courtney H. Babin

LSU New Orleans Theses and Dissertations

Polyploidy, a term used to describe organisms with cells having more than two paired sets of chromosomes, is a significant driver of diversification among land plants. Over a century of research has advanced our understanding of polyploidization in some taxa, but polyploid organisms remain understudied. In this dissertation, I investigate chromosome number evolution, phylogeographic structure, genetic differentiation, and the effects of climate change on ploidy level distribution using polyploid plant systems. In the first chapter, I inferred a molecular phylogeny of Allium, an economically important genus that includes cultivated crops and ornamentals, to investigate evolutionary transitions in chromosome number …


Development Of Graphical Models And Statistical Physics Motivated Approaches To Genomic Investigations, Yashwanth Lagisetty Aug 2022

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 …


Riverscape Community Genomics Of Ozark Fishes: A Comparative Framework To Infer Ecological And Evolutionary Determinants Of Genetic Diversity, Zachery D. Zbinden Aug 2022

Riverscape Community Genomics Of Ozark Fishes: A Comparative Framework To Infer Ecological And Evolutionary Determinants Of Genetic Diversity, Zachery D. Zbinden

Graduate Theses and Dissertations

Genetic variation is a crucial component of biodiversity and represents the variability and spatial structure of alleles within and among organisms. Evolution modulates this variability over time through mutation, selection, gene flow, and genetic drift. However, our capacity to test foundational theories of population genetics has always been at the mercy of molecular approaches available to quantify patterns of genetic diversity. Initially, techniques for empirical DNA studies were in their infancy and limited by technologies and the price per unit of genetic information. Because of these constraints, our pursuits have generally been limited to investigations of one or a few …