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Graduate Theses and Dissertations

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Full-Text Articles in Ecology and Evolutionary Biology

Bats And Bacteria: Infection Dynamics At The Human-Wildlife Interface, Isabella Katherine Deanglis May 2026

Bats And Bacteria: Infection Dynamics At The Human-Wildlife Interface, Isabella Katherine Deanglis

Graduate Theses and Dissertations

As the second most diverse mammalian order, bats host an array of pathogens, some of which are known to infect humans. Synanthropic bats share spaces with humans, resulting in bat-borne pathogen exposure. While most bat-borne disease research has focused on viral pathogens, bats host numerous bacterial pathogens with zoonotic potential. By integrating a global meta-analysis with field studies in Sub-Saharan Africa, I characterize the structural attributes that facilitate shared interfaces, the bacterial pathogens present in synanthropic bats of rural Kenya, and the physiological and environmental dynamics influencing odds of infection in these synanthropic bats. Finally, I evaluate the clinical relevance …

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Multiple Aspects Of Environmental Temperature Have Complex Interactions With Avian Parental Behavior To Influence Offspring Outcomes, William H. Kirkpatrick Dec 2025

Multiple Aspects Of Environmental Temperature Have Complex Interactions With Avian Parental Behavior To Influence Offspring Outcomes, William H. Kirkpatrick

Graduate Theses and Dissertations

Anthropogenic climate change is projected to shift not only average temperatures across the globe, but also the amount of thermal variation experienced in the natural environment. Exposure to shifts in averages and a wider range of thermal experiences will cause shifts in wildlife behavior. In avian species, behaviors exhibited during reproduction have implications for the well-being of their offspring. Here, I explore specific incubation behaviors in four species: Scaled Quail (Callipepla squamata), Northern Bobwhite Quail (Colinus virginianus), Tree Swallows (Tachycineta bicolor), and Eastern Bluebirds (Sialia sialis). I examined constancy, or the percentage of time on the nest, and off-bout duration, …

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Frogs On A Plain: Spatial Ecology Of Crawfish Frogs In Arkansas’ Remnant Prairies, Elliot T. Lassiter Dec 2024

Frogs On A Plain: Spatial Ecology Of Crawfish Frogs In Arkansas’ Remnant Prairies, Elliot T. Lassiter

Graduate Theses and Dissertations

The prairie peninsula was an expansive and important habitat that covered much of midwestern North America, from Canada to Arkansas, USA. But the prairie peninsula has shrunk by as much as 99% since 1830, and therefore, land acquisition and public/private partnerships are critical for the preservation of prairies and their associated species. In Arkansas, one species that benefits from protected prairies is the Crawfish Frog (Lithobates areolatus), which is currently declining precipitously throughout its range. Adult Crawfish Frogs spend most of their lives in terrestrial refugia (crayfish burrows), making them highly vulnerable to habitat loss and fragmentation, thereby …

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Influence Of Hydrologic And Anthropogenic Disturbance On Stream Populations And Communities, Sarah Frances Sorensen Dec 2024

Influence Of Hydrologic And Anthropogenic Disturbance On Stream Populations And Communities, Sarah Frances Sorensen

Graduate Theses and Dissertations

Disturbances occur when an external force modifies a habitat, destroying living space, removing food resources, or altering or destroying habitat structure. In lotic systems, a primary source of disturbance is hydrologic disturbance, including drought and flood. Hydrologic disturbances lead to increased mortality rates and dispersal out of disturbed habitats, causing population sizes to decrease and changes to community structures. More research is needed on how disturbances impact stream species and communities, as disturbances are predicted to become more intense with climate change. This dissertation aims to understand how disturbance influences streams at both the population and community level, through a …

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Influence Of Invasive Species, Drought, And Stream Permanence On Stream Crayfish Species With A Focus On The Imperiled Mammoth Spring Crayfish (Faxonius Marchandi), Leah Marie Bayer Aug 2024

Influence Of Invasive Species, Drought, And Stream Permanence On Stream Crayfish Species With A Focus On The Imperiled Mammoth Spring Crayfish (Faxonius Marchandi), Leah Marie Bayer

Graduate Theses and Dissertations

Freshwater crayfish constitute one of the most-threatened taxonomic groups in North America. Invasion by other crayfish species as well as habitat degradation through alteration of natural flow regime are two of the most prominent threats to crayfish persistence. Additionally, extreme weather events like droughts can amplify threats posed by other stressors on crayfish populations and are expected to increase in frequency, magnitude, and/or duration in the future, which may negatively influence narrow-ranged endemic crayfish populations typical of the Southeast. The Mammoth Spring Crayfish, Faxonius marchandi, is a narrow-ranged endemic that occurs in the Spring River drainage of Arkansas and Missouri …

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Bilateral Asymmetry In The First Metacarpal: The Influence Of Handedness In Humans And Non-Human Primates, Lucyna A. Bowland May 2024

Bilateral Asymmetry In The First Metacarpal: The Influence Of Handedness In Humans And Non-Human Primates, Lucyna A. Bowland

Graduate Theses and Dissertations

Muscle attachment sites (entheses) are often used to infer soft tissue anatomy and reconstruct behaviors within skeletal populations, but there remains a significant debate about whether and to what degree muscle use is accurately reflected in bony morphology. One of the most difficult problems in establishing the relationship between variation in muscle use and entheseal development is the inability to exclude a variety of external factors thought to influence enthesis development, including age, sex, body mass, and activity patterns. One way around this is to take advantage of the fact that humans are handed (preferentially using one hand over another, …

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Identifying Grassland Cores In The Southeast: Relating Spatial Covariance To Avian Communities And Vegetation Structure, Lauren L. Berry May 2024

Identifying Grassland Cores In The Southeast: Relating Spatial Covariance To Avian Communities And Vegetation Structure, Lauren L. Berry

Graduate Theses and Dissertations

Globally, grasslands are declining in range, which is leading to a decline in grassland-dependent taxa. These declines can be attributed to a variety of issues, a major one being the encroachment of woody species into historic grasslands. There is a new framework for strategizing grassland management, referred to as “Defend the Core,” which calls for proactive management of intact grasslands, meaning conserving remaining grasslands by preventing woody encroachment in the first place. To successfully defend the core, it is imperative that we develop rapid methods to identify intact grassland cores for management priority. One method that can be used for …

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Migration And Breeding Ecology Of King Rails (Rallus Elegans) In Southeast Arkansas, Jessica Schmit May 2024

Migration And Breeding Ecology Of King Rails (Rallus Elegans) In Southeast Arkansas, Jessica Schmit

Graduate Theses and Dissertations

King Rails (Rallus elegans) are a secretive marsh bird species of conservation concern in Arkansas. Freddie Black Choctaw West WMA in southeast Arkansas has multiple confirmed pairs of breeding King Rails and offered an opportunity to investigate King Rail migration ecology, as well as nesting ecology and nest site selection. In Chapter 1, we determined migratory status (resident vs. migratory) and described seasonal movement. To do this, we captured and outfitted 23 birds with Argos GPS tags to track migration patterns throughout the season. We found that most of the population did not make long distance migrations but instead were …

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The Causes And Consequences Of Behavioral Plasticity In Anti-Predatory Defense And Mate Choice In Tropical Butterflies, Sushant Potdar May 2024

The Causes And Consequences Of Behavioral Plasticity In Anti-Predatory Defense And Mate Choice In Tropical Butterflies, Sushant Potdar

Graduate Theses and Dissertations

Behavioral plasticity, where individuals change their behaviors in response to varying environmental and social conditions, affects major evolutionary trajectories. But how individuals change these behaviors under certain social situations, and what the genetic causes and consequences of such behavioral changes are in response to social environments are yet to be fully understood. I address these questions in the context of anti-predatory behaviors (chapter 1), and mate choice (chapters 2, 3, 4) in tropical butterflies. In the context of anti-predatory behaviors, I found predator-specific behavioral changes in toxic Heliconius butterflies, suggesting variance in predation pressures and butterfly recognition of bird calls. …

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Effects Of Seasonal Environment On Abundance, Behavior, Visual Signaling, And Perception In Prairie Butterflies, Grace Elizabeth Hirzel Dec 2023

Effects Of Seasonal Environment On Abundance, Behavior, Visual Signaling, And Perception In Prairie Butterflies, Grace Elizabeth Hirzel

Graduate Theses and Dissertations

Phenotypic plasticity is a widespread mechanism that allows animals to respond quickly to seasonal changes in their environment. However, the depth and complexity of these plastic responses is still being discovered. One aspect of seasonal physiology that is relatively unstudied is changes to sensory physiology and how it may explain changes in behavior. To determine how changes in seasonal conditions affect behavior, coloration, and vision, I examined populations of wild butterflies in Northwest Arkansas. Focusing on a single species, the common buckeye Junonia coenia, I found that seasonal coloration covaries with thermoregulating behavior and is accompanied by changes in visual …

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Patterns In Winter Stonefly Distribution Along A River Continuum And Land-Use Gradient In Northwest Arkansas Streams, Zachary Tipton Dec 2023

Patterns In Winter Stonefly Distribution Along A River Continuum And Land-Use Gradient In Northwest Arkansas Streams, Zachary Tipton

Graduate Theses and Dissertations

Freshwater ecosystems are facing a crisis with extinction rates of aquatic species exceeding those of their terrestrial counterparts by up to fivefold. This decline is predominantly attributed to evolving land use patterns within watersheds, leading to chemical and physical transformations in freshwater habitats. Northwest Arkansas (NWA) represents one of the fastest-growing regions in the United States, undergoing substantial shifts in land use. Consequently, the status of aquatic life in this region remains uncertain. Addressing this concern, the latest Arkansas Wildlife Action Plan emphasizes the necessity of distribution and population data to guide conservation efforts for Species of Greatest Conservation Need …

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Habitat Associations Of Plains Spotted Skunk (Spilogale Interrupta) Across The Plains Ecoregion. And The Landcover Occupancy Models Of The Gray Fox (Urocyon Cinereoargenteus) In The Southeastern Plains Region In Arkansas, Michael Shaw Dec 2023

Habitat Associations Of Plains Spotted Skunk (Spilogale Interrupta) Across The Plains Ecoregion. And The Landcover Occupancy Models Of The Gray Fox (Urocyon Cinereoargenteus) In The Southeastern Plains Region In Arkansas, Michael Shaw

Graduate Theses and Dissertations

Much of the landscape of the United States has been altered by humans, leading to the eradication of most populations of large mammalian predators. Consequently, many species of mammalian mesopredators (medium-sized mammalian predators) have come to dominate the landscape. Species such as the gray fox (Urocyon cinereoargenteus) may appear to be on the rise and doing well due to their widespread range, but at a local scale may need monitoring and less is known in areas of its range. Others such as the plains spotted skunk have a wide range across the plains but are on the decline even with …

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Exploring The Interrelationships Among Structural Complexity, Multi-Trophic Biodiversity, And Ecosystem Productivity In Forested Ecosystems., Ayanna St. Rose Dec 2023

Exploring The Interrelationships Among Structural Complexity, Multi-Trophic Biodiversity, And Ecosystem Productivity In Forested Ecosystems., Ayanna St. Rose

Graduate Theses and Dissertations

Forests play a pivotal role in sustaining global biodiversity and mitigating the global climate, as they serve as the primary refuge for terrestrial biodiversity and effectively capture and store atmospheric carbon dioxide. However, changing climate and land use are altering the geographic distribution, physical structure, and productivity of forested ecosystems that can have profound impacts on biodiversity conservation, forest productivity, and global climate. This dissertation contributes to our understanding of multifaceted interactions between the physical and biological structural complexity and ecosystem functions in forested landscapes across the United states by using openly available data from two national networks: the National …

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Human-Bat Interactions In A Disease Emergence Hotspot: Implications For Human Health And Bat Conservation, Reilly Tempest Jackson Dec 2023

Human-Bat Interactions In A Disease Emergence Hotspot: Implications For Human Health And Bat Conservation, Reilly Tempest Jackson

Graduate Theses and Dissertations

Bats are an ecologically important taxon that can host zoonotic pathogens. Globally, many bat species are synanthropic and live closely with humans, often roosting in man-made structures. The spatial overlap between humans and bats creates opportunities for human-bat contact, which can lead to human exposure to bat-borne pathogens and conflicts that cause bat mortality. Despite this risk, little is known about the drivers and characteristics of these human-bat interactions in buildings and work is needed to understand this aspect of the wildlife-urban interface. In Chapter I, I present a literature review that identifies the geographic and taxonomic trends in reported …

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The Effect Of Symbioses Between Mold Mites (Acaridae: Tyrophagus Putrescentiae) And Aspergillus Flavus On Their Respective Populations In Stored Maize., Paige Pionke Cummins Aug 2023

The Effect Of Symbioses Between Mold Mites (Acaridae: Tyrophagus Putrescentiae) And Aspergillus Flavus On Their Respective Populations In Stored Maize., Paige Pionke Cummins

Graduate Theses and Dissertations

Zea mays is the most commonly grown grain in the world and is used for animal feed, human consumption, and the creation of other products such as ethanol and bioplastics. Contamination of stored maize with stored grain invaders can lead to loss of revenue, reduced food availability, and potential health complications. Two such storage invaders; the mold mite Tyrophagus putrescentiae and the fungus Aspergillus flavus can work as symbionts within the grain storage system. To determine resulting population growth from this symbiosis, maize was inoculated with three treatments: A. flavus with no mites, T. putrescentiae with no fungus, and both …

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Generation Z’S Perceptions Of Hunting And Conservation Efforts In Arkansas, Hannah Ferguson Aug 2023

Generation Z’S Perceptions Of Hunting And Conservation Efforts In Arkansas, Hannah Ferguson

Graduate Theses and Dissertations

Hunting participation numbers have steadily declined since the 1980s and Generation Z is not engaging in hunting. Hunting is one of the most effective tools for managing wildlife populations and ensuring the success and local ecosystem conservation. Many wildlife stewardship institutions, such as Arkansas Game and Fish Commission in Arkansas, are funded by sales taxes imposed on firearms, ammo, and archery equipment. With a decline in hunting participation, it is imperative state-run wildlife stewardship organizations and other hunting institutions learn the best practices for communicating with younger generations. This study sought to understand Generation Z’s perceptions of hunting and conservation …

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Shedding In The Timber Rattlesnake: Natural Patterns, Endocrinological Underpinnings, Temporal And Energetic Effort, And Integration As A Reptilian Life History Trait, Maxwell D. Carnes-Mason Aug 2023

Shedding In The Timber Rattlesnake: Natural Patterns, Endocrinological Underpinnings, Temporal And Energetic Effort, And Integration As A Reptilian Life History Trait, Maxwell D. Carnes-Mason

Graduate Theses and Dissertations

The semi-frequent replacement of the epidermis (ecdysis) is a characteristic trait of reptiles. Whereas all reptiles regularly engage in some degree of skin shedding, skin morphology in snakes necessitates the synchronous replacement of the entire epidermis and facilitates the subsequent removal of the old layer as a single sheet. To date, the ubiquitous process has garnered little attention from researchers because snakes shed with unpredictable timing and frequency and are exceedingly cryptic during ecdytic cycles; previously impeding detailed physiological or ecological investigations of the process in the clade. Because of the lack of study, ecdysis is often viewed as a …

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The Influence Of Climate And Landscape On Allocapnia Mohri Distribution In Arkansas, Brianna Leigh Annaratone Aug 2023

The Influence Of Climate And Landscape On Allocapnia Mohri Distribution In Arkansas, Brianna Leigh Annaratone

Graduate Theses and Dissertations

Stoneflies are a globally threatened aquatic insect order. In Arkansas, a diverse group of winter stonefly (Capniidae: Allocapnia) have not been surveyed since the 1980s, likely because species-level identification requires the rarely-collected adult form. Allocapnia mohri, a regional endemic, was previously commonly found in mountainous, intermittent streams from the Ouachita Mountains ecoregion north to the Ozark Highlands, but no species distributional models including land use or climate variables exist to our knowledge. We collected adults from 70 stream reaches from the historic Arkansas range from November to April 2020 and 2021. We modeled distributions using random forest (RF) models populated …

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Unveiling The Ancestral Function Of A Neuroendocrine Regulator, Pou-I/Pit1: Insights From Gene Expression Analysis In The Sea Anemone Nematostella Vectensis, Miguel Agostinho Pina Da Silva May 2023

Unveiling The Ancestral Function Of A Neuroendocrine Regulator, Pou-I/Pit1: Insights From Gene Expression Analysis In The Sea Anemone Nematostella Vectensis, Miguel Agostinho Pina Da Silva

Graduate Theses and Dissertations

Cnidaria (i.e., sea anemones, jellyfish, corals) and Bilateria (i.e., vertebrates, sea stars, fruit flies), are sister groups that diverged around 600 million years ago. Despite the long evolutionary time, many cellular differentiation mechanisms, cell types, tissues and behaviors are conserved. Such as neurons, mechanosensory hair cells, feeding behaviors, peristaltic movements, and sleep. Recent advances in genomics, molecular biology and microscopy have fueled an increased interest in understanding cnidarian nervous and neuroendocrine systems. Understanding the developmental mechanisms and the mode of operation of Cnidarian nervous systems helps to reconstruct the ancestral nervous system of the last common ancestor of Cnidaria and …

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Ecological, Evolutionary, And Temporal Dynamics Of Animal Mortality Events, Simon Patrick Tye May 2023

Ecological, Evolutionary, And Temporal Dynamics Of Animal Mortality Events, Simon Patrick Tye

Graduate Theses and Dissertations

Global declines of animal abundances are emblematic of the Anthropocene. Recent animal declines have increasingly involved more frequent and intense die-offs within populations, or mass mortality events (MMEs). These extreme demographic events can lead to rapid changes in biological communities, either by imperiling the affected population or influencing populations remaining within communities. To date, there is still limited information about the effects of predator MMEs on immediate ecological dynamics within communities and rapid evolutionary dynamics within remaining populations that may ensue. Moreover, few approaches exist to predict future occurrences of predator MMEs across broad spatial scales. To address these gaps, …

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An Ecological Perspective Of American Rodent-Borne Orthohantavirus Surveillance, Nathaniel Mull May 2023

An Ecological Perspective Of American Rodent-Borne Orthohantavirus Surveillance, Nathaniel Mull

Graduate Theses and Dissertations

Orthohantaviruses are a global group of viruses found primarily in rodents, though several viruses have also been found in shrews and moles. Many rodent-borne orthohantaviruses are capable of causing one of several diseases in humans, and the mortality associated with these diseases ranges from < 0.1% - 50% depending on the specific etiological virus. In North and South America, orthohantavirus research was ignited by an outbreak of severe disease in the Four Corners region of the United States in 1993. However, despite the discovery of over 20 orthohantaviruses in the Americas, our understanding of orthohantavirus ecology and virus-host dynamics in this region is still limited, and orthohantavirus surveillance is generally restricted in scope to select regions and small portions of host distributional ranges. In Chapter I, I present a literature review on the current understanding of American rodent-borne orthohantavirus ecology. This review focused on under-studied orthohantaviruses, addressing gaps in knowledge by extrapolating information from well-studied orthohantaviruses, general rodent ecology, and occassionally from Eurasian orthohantavirus-host ecology. There were several key conclusions generated from this review that warrant further research: 1) the large number of putative orthohantaviruses and gaps in orthohantavirus evolution necessitate further surveillance and characterization, 2) orthohantavirus traits differ and are more generalizable based on host taxonomy rather than geography, and 3) orthohantavirus host species are disproportionately found in grasslands and disturbed habitats. In Chapter II, I present a prioritized list of rodent species to target for orthohantavirus surveillance based on predictive modeling using machine learning. Probable orthohantavirus hosts were predicted based on traits of known orthohantavirus hosts using two different types of evidence: RT-PCR and virus isolation. Predicted host distributions were also mapped to identify geographic hotspots to spatially guide future surveillance efforts. In Chapter III, I present a framework for understanding and predicting orthohantavirus traits based on reservoir host phylogeny, as opposed to the traditional geographic dichotomy used to group orthohantaviruses. This framework establishes three distinct orthohantavirus groups: murid-borne orthohantaviruses, arvicoline-borne orthohantaviruses, and non-arvicoline cricetid-borne orthohantaviruses, which differ in several key traits, including the human disease they cause, transmission routes, and virus-host fidelity. In Chapter IV, I compare rodent communities and orthohantavirus prevalence among grassland management regimes. Sites that were periodically burned had high rodent diversity and a high proportion of grassland species. However, rodent seroprevalence for orthohantavirus was also highest in burned sites, representing a trade-off in habitat management outcomes. The high seroprevalence in burned sites is likely due to the robust populations supported by the high quality habitat resulting from prescribed burning. In Chapters V and VI, I describe Ozark virus and Sager Creek virus, two novel orthohantaviruses discovered from specimens collected during Chapter IV. Both chapters report full genome sequences of the respective viruses and compare both nucleotide and protein phylogenies with related orthohantaviruses. Additionally in Chapter VI, I support the genetic analyses with molecular and ecological characterizations, including seasonal fluctuations in host abundance, correlates of prevalence, evidence of virus shedding, and information on host cell susceptibility to Sager Creek virus.

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Factors That Affect Home Range Of Timber Rattlesnakes (Crotalus Horridus) In Northwest Arkansas, Bannon Gallaher May 2023

Factors That Affect Home Range Of Timber Rattlesnakes (Crotalus Horridus) In Northwest Arkansas, Bannon Gallaher

Graduate Theses and Dissertations

Conservation of animal populations requires knowledge of their habitat and spatial needs. Quantifying spatial requirements involves the analysis of home range. We examined the effects of sex, body size (SVL), body condition (log mass/log SVL), and year on home range in Timber Rattlesnakes (Crotalus horridus) in Northwest Arkansas. Individual locality data from an ongoing, 22+ year radio-telemetry study in Madison Co., Arkansas were analyzed using both minimum convex polygon (MCP) and Kernel Density Estimates (KDE). Plots of the number of sequential observations versus home range (MCP and KDE) determined that a minimum of 25 locations per individual per active season …

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Effects Of Landscape And Yard Features On Mammals In Residential Yards In Northwest Arkansas, Emily Johansson May 2023

Effects Of Landscape And Yard Features On Mammals In Residential Yards In Northwest Arkansas, Emily Johansson

Graduate Theses and Dissertations

The human footprint is rapidly expanding, and wildlife habitat is continuously being converted to human residential properties. Most wildlife residing in developing areas are displaced to nearby undeveloped areas. However, some animals can coexist with humans and acquire the necessary resources (food, water, shelter) within the human environment. This may be particularly true when development is low intensity, as in suburban yards. Due to the wide variety in how homeowners utilize their yards, they can be considered individually managed “greenspaces.” These yards can provide a range of food (e.g., bird feeders, compost, gardens), water (bird baths and garden ponds), and …

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Ecology, Evolution, And Gene Transfer Between Diatoms And Bacteria, Cory B. Gargas May 2023

Ecology, Evolution, And Gene Transfer Between Diatoms And Bacteria, Cory B. Gargas

Graduate Theses and Dissertations

Although photosynthetic macro-eukaryotes (i.e., plants) make up the majority of organic biomass on earth, bacteria are the second largest taxonomic group, by biomass. Bacteria are ubiquitous in our environment, living on, and within, man-made surfaces, natural environments, and eukaryotes themselves. The relationship between bacteria and eukaryotes has existed from the very beginning of eukaryotic life in the form of bacterial endosymbioses that resulted in mitochondria and plastids. Other eukaryote–bacteria relationships have evolved since then, ranging from the beneficial (e.g., mutualistic) to harmful (e.g., parasitic or pathogenic). Understanding these eukaryote–bacteria relationships is key to understanding both the evolution of important ecosystem …

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Seasonal Patterns In Activity And Occupancy Dynamics Of The Imperiled Spotted Turtle (Clemmys Guttata), Ellery Vaughn Lassiter Dec 2022

Seasonal Patterns In Activity And Occupancy Dynamics Of The Imperiled Spotted Turtle (Clemmys Guttata), Ellery Vaughn Lassiter

Graduate Theses and Dissertations

Wetland ecosystems are often spatially patchy across a landscape and exhibit seasonal patterns in water levels, resulting in the need for aquatic wildlife to use several different wetland patches across a season. The ecology of semi-aquatic freshwater turtles is especially complex because individuals often move among a variety of habitats to meet life history needs and these habitat requirements often differ across a season. Understanding the temporal and spatial scale in which turtles move and distribute across the landscape is vital for effective management, especially in the face of continued habitat fragmentation and climate change. Thus, we sought to understand …

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Hiding In Plain Sight: Accounting For Rate Heterogeneity In Trait Evolution Models, James Boyko Aug 2022

Hiding In Plain Sight: Accounting For Rate Heterogeneity In Trait Evolution Models, James Boyko

Graduate Theses and Dissertations

Within the last four decades, phylogenetic comparative methods have become the defacto method of analysis for comparative biologists. The availability of high-quality comparative datasets has been matched by an explosion of possible phylogenetic models. In large part, the efforts to increase the realism of phylogenetic comparative methods has been successful as evidenced by their widespread use. To this extensive literature, my contributions are modest. I have focused my dissertation work on two main themes. First, most phenotypic evolution is not independent of other phenotypes. Changes in a particular character may influence changes in another and modeling these characters in isolation …

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Bacterial Chondronecrosis With Osteomyelitis In Broilers: Genomics, Phylogenomics, And Methods To Detect Specific Pathogens During Outbreaks., Abdulkarim Abdulaziz A. Shwani Aug 2022

Bacterial Chondronecrosis With Osteomyelitis In Broilers: Genomics, Phylogenomics, And Methods To Detect Specific Pathogens During Outbreaks., Abdulkarim Abdulaziz A. Shwani

Graduate Theses and Dissertations

Lameness is a major issue in animal welfare and the broiler industry. Bacterial chondronecrosis with osteomyelitis (BCO) is one of the main causes of lameness. Many staphylococcal species, including Staphylococcus agnetis isolate 908, have been isolated from the bones and blood of lame broilers at the University of Arkansas. Staphylococcus agnetis is a coagulase-variable, Gram-positive bacterial species that has been previously associated with subclinical or mild clinical cases of mastitis in dairy cattle. The annotated complete genome of hypervirulent strain 908 was published at NCBI. In this study, it has been compared to nine genomes we assembled for hypervirulent isolates …

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Patterns Of Evolutionary Conservation And Divergence In The Short-Term Hyposalinity Stress Response Of A Euryhaline Diatom, Skeletonema Marinoi, Kathryn Judy Aug 2022

Patterns Of Evolutionary Conservation And Divergence In The Short-Term Hyposalinity Stress Response Of A Euryhaline Diatom, Skeletonema Marinoi, Kathryn Judy

Graduate Theses and Dissertations

Survival under fluctuating environmental conditions, such as those increasing in frequency and magnitude under environmental change, requires a successful response to stress. Interspecific differences in stress responses may result in differential survival of species, even within a lineage. Diatoms may constitute one such lineage, as salinity tolerance among extant species is diverse, and the observation of frequent historic habitat transitions between marine and freshwater environments indicates that diatoms successfully mitigated (low) salinity stress in the past, followed by adaptation and diversification over evolutionary time scales. To understand to what extent the diatom hypoosmotic stress response consists of conserved and variable …

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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 …

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Conservation Of Open-Canopy-Associated Wildlife: Multi-Scale Management Impacts On Imperiled Herpetofauna, Ethan Joseph Royal Aug 2022

Conservation Of Open-Canopy-Associated Wildlife: Multi-Scale Management Impacts On Imperiled Herpetofauna, Ethan Joseph Royal

Graduate Theses and Dissertations

The loss of open-canopy ecosystems throughout North America has precipitated declines in reptile and amphibian species associated with these habitat types. Current efforts to restore open-canopy ecosystems are underway in many areas, but the local distributions of, habitat characteristics required by and the effects of management actions on many herpetofauna species are poorly understood or entirely unknown. Research examining relationships among herpetofauna and their environments is often complicated by the extremely low detectability seen in many studies. We used landscape-scale, assemblage-level surveys to investigate the occupancy patterns and habitat associations of open-canopy-associated herpetofauna in two regions, as well as gain …

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