Ecology and Evolutionary Biology Commons^™

Leveraging Mammal Mycophagy To Determine Environmental Drivers Of Truffle Diversity, Brittany Hartsock

Electronic Theses and Dissertations

Many mycorrhizal fungi are hypogeous (truffle-forming), producing underground fruiting bodies. Studying truffles is inherently challenging due to their hidden nature. However, mycophagous mammals provide a unique opportunity to study hypogeous fungi because they rely on truffles as a food source. Although several truffle species have recently been described in the southern Appalachian region, their fruiting patterns remain poorly understood. To address this, we quantified truffle richness and spore loads from 670 Peromyscus scat samples collected across 42 sites spanning an environmental gradient during 2024 in the Blue Ridge Mountains of East Tennessee. We found that truffle richness and spore abundance …

Exploring Foundations Of Animal Host-Microbe Interactions In A Freshwater Sponge, Jacob S. Pawley

Electronic Theses and Dissertations

The most ancient eukaryotic immune defense mechanisms evolved in unicellular species. Multicellular eukaryotes, however, expanded these mechanisms to meet challenges unique to multicellular life, including barrier formation, long-distance cell signaling, and coordinated responses that eliminate microbial threats while minimizing damage to the host. As such, animal immune signaling pathways are exceptionally intricate and diverse. Though, most of what is understood about animal host–microbe interactions stems from a small handful of model systems. Here, I evaluate host–microbe interactions and innate immunity in sponges using the highly tractable freshwater sponge, Ephydatia muelleri. I report the discovery of an external host-derived matrix …

A Geometric Morphometric Analysis Of Acetabular Shape Variation Across Bat Families, Jordan L. Huff

Electronic Theses and Dissertations

Bats are the only mammals capable of powered flight, and research is concentrated on this adaptation. Their non-flight locomotion has received comparatively little attention. Previous studies show that non-flight locomotor behaviors vary across families. Members of Pteropodidae are efficient climbers but cannot effectively walk, whereas Phyllostomidae and Vespertilionidae are better at terrestrial locomotion but show reduced arboreal capabilities. The non-flight locomotion of Hipposideridae and Rhinolophidae is less understood, although rhinolophids exhibit limited terrestrial locomotion. This study examined whether differences in locomotor behavior are associated with variation in acetabular morphology. A geometric morphometric analysis of acetabular shape was conducted across multiple …

Examining Individual Representation In Asian Elephants (Elephas Maximus): Implications For Recognizing Familiarity And Presence Of Conspecifics, Elena Lawson

Electronic Theses and Dissertations

Elephants’ flexible cognitive abilities and fission-fusion societies make them an excellent study species to investigate individual social recognition. Despite the substantial role chemical cues play in elephant social communication, there is a considerable lack of research into their chemosensory social recognition, especially in Asian elephants (Elephas maximus). Using two-choice tests, I assessed Asian elephants’ chemosensory ability to discriminate between individuals by both presence and familiarity. I also used a habituation-discrimination paradigm to assess individual recognition in elephants by determining whether elephants integrate odor cues (i.e., urine and feces) to form multi-cue representations of individuals. Responses between samples were …

The Palm Farm Next-Door: Land Concessions, Livelihoods, And Nutrition In Plantation-Adjacent Communities, Julia Entwistle

Electronic Theses and Dissertations

Large-scale land concessions have reshaped agrarian landscapes globally, yet their implications for community land tenure, livelihoods, and nutrition remain unevenly understood. This dissertation examines how plantation agriculture and foreign investment have transformed land access, labor relations, and food systems in Liberia, a country with one of the highest proportions of land under concession globally. Guided by a political ecology framework, the study employs a mixed-methods design integrating policy analysis, in-depth interviews, and household surveys across two palm oil concession sites. The findings show that ambiguous land policies historically facilitated dispossession, while recent legal reforms have enabled communities to strategically mobilize …

Ontogeny And The Effects Of Perinatal Stress In The First Immature Skeleton Of Teleoceras Aepysoma (Perissodactyla, Rhinocerotidae), Joe Gajewski

Electronic Theses and Dissertations

Recovery of an immature fossil rhinoceros (Teleoceras aepysoma) skeleton (ETMNH 32999) from the Gray Fossil Site in Tennessee offers the first insights into the ontogeny of the species. ETMNH 32999 is interpreted to be a subadult male in an age class equivalent to ~17-20% of potential lifespan. Comparative analyses support the hypothesis that subadults of related taxa are typically ~91% of average adult size in most dimensions. However, certain cranial dimensions are substantially lower than expected in ETMNH 32999, averaging only ~74% of the average conspecific adult. Such departure from typical growth rates is suggested to be attributable …

Floodwater Salinity And Flood Duration Regulate Greenhouse Gas Production In High- Latitude Coastal Wetland And Tundra Soils, Mia J. Dicianna

Electronic Theses and Dissertations

Coastal high-latitude ecosystems are increasingly flooded from storm surges associated with climate change, exposing soils that were historically infrequently inundated to higher-salinity waters for longer durations. Sub-Arctic wetlands and tundra store large amounts of carbon, yet how flooding characteristics, particularly flood duration, influence microbial mineralization and, consequently, greenhouse gas (GHG) production in these soils remains poorly understood. We conducted a full-factorial microcosm incubation experiment in which coastal wetland and tundra soils were subjected to simulated flooding with three durations (1, 3, and 10 days) and four salinity treatments (unflooded, freshwater, 3 ppt, and 12 ppt) and measured carbon dioxide (CO2) …

Evaluating Planting Methods For Native Seed Production And Exploring Granivory In The Northern Great Plains, Allison Dollen

Electronic Theses and Dissertations

Temperate grasslands have faced immense losses due to land use change in the last 150 years and less than half of the overall grasslands that once covered North America remain today. A portion of historic and remaining U.S. grasslands are located within the northern Great Plains (NGP) region which is home to over 1,600 species of native plants and provides many ecosystem services and economic benefits. Initiatives to restore grasslands and their ecosystem services are currently underway, but barriers such as limited native seed supply and granivory hinder restoration efforts. My first chapter addresses knowledge gaps in planting methods for …

Chemical Load: An Unseen Herbicide Filter In Restored Prairies?, Rylie Franklin

Electronic Theses and Dissertations

Community Assembly Theory is a framework used to describe the process by which species from a regional species pool disperse and encounter various abiotic and biotic conditions that act as filters, limiting which species will populate a specific local community. Prairie restoration success can be improved by understanding abiotic and biotic filters. As agricultural practices have adopted integrated weed management plans, that include the use of both chemical and non-chemical techniques, another filter needs to be considered during restoration: the chemical load of soils, i.e., herbicide residue from recent on-site applications and herbicide drift from adjacent areas. To examine the …

The Ecology Of Arthropod Rain In A Tropical Forest., Andrew Robert Seiler

Electronic Theses and Dissertations

Tropical forests are structured by complex vertical linkages and nutrient exchanges between canopy and understory habitats. These linkages include the downward flux of organisms, the movement of canopy fauna, and the recycling of nutrients through litter and organic matter deposition. This dissertation investigates arthropod rain and its role in connecting the canopy and forest floor processes in a lowland tropical forest in Panama. Chapter 2 quantifies “arthropod rain”, the fall of canopy arthropods into the understory. Using pan and pole traps, I measured the composition, abundance, and biomass of arthropods falling from the canopy and assessed environmental drivers of the …

Ecosystem Services Of Urban Green Spaces In Louisville, Ky., Julia Kachanova

Electronic Theses and Dissertations

Accelerating urbanization poses critical challenges to urban green spaces (UGS), vital for ecological balance and human health. Rapid development often results in fragmented habitats, biodiversity loss, and diminished ecosystem service delivery. There is an urgent need to explore and evaluate novel strategies capable of enhancing urban resilience, such as implementing urban orchards, and managing existing parks and gardens in sustainable ways. This dissertation explores how different forms of urban green spaces (UGS) contribute to the provision and maintenance of critical ecosystem services that support human well-being and urban biodiversity. By analyzing UGS impact on ecosystem service provisioning and long-term sustainability, …

Changing Globally, Acting Locally: Responses Of Coastal Plant Functional Traits To Global Change Are Mediated By Biotic And Abiotic Interactions., Shannon L. Walker

Electronic Theses and Dissertations

We live in a time of rapid global change with substantial consequences for planet-wide functioning. Local ecosystems reflect this change, yet we struggle to predict their responses. Coastal ecosystems, like dune and interdunal wetlands, have declined rapidly and predicting their responses to global change is essential for future management. Functional traits may be particularly informative as they drive species and ecosystem responses and can provide generalizable findings. This dissertation investigates how global change, especially anthropogenic nitrogen (N) enrichment, interacts with abiotic and biotic factors to affect coastal sand dune and interdunal wetland plant functional traits. First, I used a long-term …

Linked Lives In The Riverbed: Integrating Fish Host Dynamics, Community Structure, And Demography For Freshwater Mussel Conservation., Jonathan Patrick Frommeyer

Electronic Theses and Dissertations

Freshwater mussels are long-lived benthic invertebrates that play key roles in nutrient cycling, water filtration, and habitat stability in rivers and streams. Despite their ecological importance, they are among the most imperiled faunal groups in North America, with their persistence increasingly threatened by environmental degradation and disruptions to host–parasite dynamics. This dissertation integrates host ecology, community structure, and demographic modeling to assess population viability and guide conservation priorities for mussel species in Kentucky river systems. The first chapter introduces the ecological context and conservation urgency surrounding freshwater mussels. In particular, emphasizing the need for multi-scale approaches to understand how parasitic …

Coastal Transition Zone Development Effects On Salt Marsh Ecology, Amanda Mei Pysher

Electronic Theses and Dissertations

The coastal transition zone (CTZ) is a regional gradient linking terrestrial and marine systems, comprising of the terrestrial upland, the marsh-upland ecotone, and estuarine salt marshes. Along all US coastlines, including the South Carolina (SC) coast from Little River to Georgetown, increases in anthropogenic development of terrestrial uplands have altered the historically established vegetation, and various physical, chemical, biological, and geological gradients. Despite the CTZ's ecological importance, the trickle-down effects of terrestrial upland development on associated high marsh habitats remain understudied. Data were collected from developed (DEV) and undeveloped (UND) shorelines across three SC estuarine inlets. Multilevel modeling (MLM) was …

Site Fidelity, Seasonality, Movement, And Fish Associates Of Sand Tigers Carcharias Taurus In North Carolina, Ara L. Mcclanahan

Electronic Theses and Dissertations

Sand tigers Carcharias taurus are mackerel sharks with a disjunct global distribution in tropical and temperate seas. In the northwest Atlantic, sand tigers migrate along the coast of the eastern United States from the Gulf of Maine to Florida and occupy structurally complex benthic habitats. The long-term, underwater camera installation, SharkCam, at Frying Pan Tower, off Cape Fear, North Carolina, USA, sits atop an expanse of hard bottom reef frequented by sand tigers. The citizen-science platform Spot A Shark USA (SAS USA) uses images of sand tigers to identify and track individuals. This study utilized image encounters from SAS USA …

Gut Passage Time In Small Mammals: Influences Of Small Mammal Traits, Digesta Phase, And Particle Morphology, Noah G. Hale

Electronic Theses and Dissertations

Dispersal is crucial in maintaining healthy ecosystems, but little is known about mechanisms influencing fungal spore dispersal by animals. We aimed to develop a more mechanistic understanding of the influence of fungal spore traits and small mammal traits on gut retention time. We fed three species of small mammals (shrew, mouse, vole), which differ in gut morphologies, digestive strategies, and activity a combination of markers including: liquid digesta phase (CrEDTA), small particle (fungal spores with diverse morphologies), and large particles (glitter and beads, representing plant cells and seeds, respectively). We found that hindgut fermenters selectively retained the liquid markers, spores …

Mixture Effects On Metal Accumulation In The Asian Clam, Corbicula Fluminea, Mark A. Huff

Electronic Theses and Dissertations

Field collected Corbicula fluminea were exposed to trace level copper, lead, and zinc with the aim of examining the preferential accumulation between the soft tissue and shell. Metal levels were based on those in a permitted industrial effluent. At 1X effluent and 2X effluent exposure levels, copper was found to preferentially accumulate in the clam soft tissue, lead was found to preferentially accumulate in the clam shell, and zinc was found to excrete back into the diluent after preferentially accumulating in the clam soft tissue. When exposed as a mixture at 1X effluent levels, copper and lead were found to …

Evaluation Of A Forest Restoration Strategy On Small Mammals In Southern Pine Ecosystems, Gage R. Grantham, Jessica L. Glasscock, Christopher M. Schalk, Kathryn R. Kiid, Reuber Antoniazzi

Electronic Theses and Dissertations

Industrial forestry replanted historic native pine forests (e.g., longleaf pine [Pinus palustris] and shortleaf pine [Pinus echinata]) to homogenous, high-density plantations consisting of native off-site species (e.g., loblolly pine [Pinus taeda]) after intensive harvesting for wood products. The contemporary forest structure that remains, consisting of off-site overstory compositions, can potentially serve as an ecological bridge to facilitate a gradual transition to a more desirable canopy species, thereby conserving biodiversity and ecosystem function. Understanding disturbance-sensitive small mammal communities from restoration strategies (retention) can help achieve long-term management goals for ecosystem conservation across larger scales. I …

Evaluating Quadrupedal Locomotion In Bats: A Geometric Morphometric Comparison Of Vertebral Adaptations Across Mammals, Jessica Upham

Electronic Theses and Dissertations

Flight is the primary locomotion of bats, while quadrupedal locomotion is not often observed and is widely variable among bats. Frugivorous bats in Pteropodidae are more efficient climbers than frugivorous bats in Phyllostomidae and insectivorous bats in Vespertilionidae, while phyllostomids and vespertilionids are better at walking on horizontal surfaces. The aim of this study is to investigate whether bats with differing modes of nonflight locomotion also exhibit disparity in thoracolumbar vertebral morphology. Using geometric morphometrics, we compared the thoracolumbar vertebral shapes of these bat families with other terrestrial and arboreal mammals. The results revealed distinct vertebral shapes among bat families …

Cattle Regenerative Grazing Effects On Bat Activity In Southern Appalachia, Seth Morelock

Electronic Theses and Dissertations

Livestock farming accounts for about 70% of agricultural activity, with continuous grazing as the dominant conventional practice. However, this method often degrades biodiversity and ecosystem health through overgrazing. Regenerative grazing practices offer a potential ecologically sustainable approach to cattle management. Insectivorous bats are known to use agroecosystems for foraging and roosting habitats, offering an opportunity to assess their response to regenerative grazing. Using passive acoustic monitors, we evaluated the response of bats to cattle within regenerative grazed farms in East Tennessee, USA. Overall bat activity declined when cattle entered and exited paddocks, except for the tri-colored bat (Perimyotis subflavus …

Investigating The Impact Of Psychoactive Plant Alkaloids On Bumblebee Behavior, Skylar Mathieson

Electronic Theses and Dissertations

The relationship between plants and their pollinators is often framed as a food-for-service exchange in which plants provide pollinators with nutrients in exchange for transport of their gametes. However, in addition to essential nutrients, many floral rewards (nectar, pollen) also contain defensive toxins such as alkaloids, with largely unexplored consequences for plant-pollinator interactions. I investigated how three psychoactive and addictive plant alkaloids — caffeine, nicotine, and morphine — affect foraging behavior in generalist bumblebees (Bombus impatiens) using robotic flowers. Each of these chemicals affected pollinator foraging behavior, influencing the number and duration of their visits to flowers in …

Drivers And Consequences Of Changes In Nectar Microbiome Composition Across Spatial And Biological Scales, Daniel A. Barker

Electronic Theses and Dissertations

Microbial communities inhabiting floral nectar, known as the nectar microbiome, are important mediators of plant-pollinator interactions. However, the ecological and environmental factors that shape the composition of these microbial communities remain poorly understood. While previous studies have examined the effects of a few microbial groups, typically independent of one another, on one plant or pollinator species, this dissertation takes a wide-scale approach to explore how abiotic conditions and biotic interaction’s structure microbial communities within floral nectar. Furthermore, I also quantify how variation in microbial richness and identity influences pollinator behavior and plant reproductive success.

This dissertation shows that microbial abundance …

Impact Of Unconventional Gas Extraction On Tributaries Of Tenmile Creek, Greene County, Pennsylvania: A 12-Year Perspective, Christian L. Beall

Electronic Theses and Dissertations

Much of southwestern Pennsylvania has been central to a rapid increase in development for unconventional natural gas extraction in the past two decades. The continued monitoring of streams over their lifetime as extraction sites is pivotal to understanding the effects of fracking on local waterways and their ability to provide for wildlife and human use. Here, using multiple indices of biotic integrity (IBI), I perform analyses of fish and macroinvertebrate communities as well as water chemistry on two streams, Bates Fork (with shale wells) and Fonner Run (without), as part of a follow-up to work performed there from 2010-2012. Fish …

Demography Of Alligator Snapping Turtles (Macrochelys Temminckii) Along A Fishing Pressure Gradient, Luke T. Micek

Electronic Theses and Dissertations

Passive fishing gear is a threat to the alligator snapping turtle (Macrochelys temminckii). The spatio-temporal persistence of this threat and its impacts on M. temminckii populations has not been quantified. I quantified the density of passive fishing gear and the demographic parameters of M. temminckii along a fishing pressure gradient in East Texas streams. Most gear was abandoned and illegally deployed, with densities varying seasonally. Detectability of passive fishing gear declined with increasing gear age, water depth, and volume, but increased with increasing precipitation. Macrochelys temminckii catch per unit effort, abundance, and survival was lower at sites with …

Patterns Of Taxonomic, Functional, And Phylogenetic Diversity, And Ecological Drivers Of Stream Fish Assemblages In East Texas, Anastasia M. Umstott

Electronic Theses and Dissertations

Freshwater ecosystems in East Texas contain a rich freshwater biodiversity, with the Neches and Sabine River basins supporting some of the greatest freshwater fish diversity in the state. Given the heterogeneity of habitats and species diversity, these rivers serve as excellent natural systems for examining the ecological processes shaping biodiversity patterns and species distributions. In 2023-2024, 60 streams in the Neches and Sabine River basins were surveyed across three seasons to investigate the patterns and ecological drivers of taxonomic (TDβ), functional (FDβ), and phylogenetic β-diversity (PDβ) facets of freshwater fish assemblages. Additionally, I created two ecological niche models for a …

The Impacts Of Management Practices On Industrial Hemp Chemistry, Physiology, And Microbiome Ecology., Allison Marie Rietman

Electronic Theses and Dissertations

Agroecology incorporates ecology and agronomy to inform crop management. Industrial hemp (Cannabis sativa L.) is a prime system to investigate agroecological questions because it has only recently been authorized for commercial cultivation and its sensitivity to biotic and abiotic stressors is unresolved. Here, I investigate how some conventional management choices, including the application of fungicide, plastic mulch, and irrigation, impact the physiology, chemistry, and microbial ecology of industrial hemp. Overall, I found that industrial hemp can be both resilient and resistant to these stressors, an important development for the industry. In Chapter II, I tested the impacts of fungicide application …

The Effects Of Geographic Isolation And Anthropogenic Activity On The Social Behavior Of Caribbean Green Monkeys., Rose Amrhein

Electronic Theses and Dissertations

Green monkeys (Chlorocebus sabaeaus) arrived to the Caribbean with the Trans-Atlantic slave trade. Since then, they have experienced unique environments to those of their native ranges in West Africa. Additionally, recent taxonomic changes within the genus make previous knowledge about the species hard to determine to be accurate. In this dissertation, I both assess some of the effects the island environment may have had on monkey behavior as well as build on the understanding of their vocal communication across three islands: Barbados, St. Kitts, and St. Martin. In chapter one, I investigate how human activity in Barbados affects …

Life History Inhibits Deleterious Effects Of Dams On Genetic Health And Structure Of A Headwater Stream Fish, Riley Phelps

Electronic Theses and Dissertations

Habitat loss, fragmentation, and land use changes in river networks are common globally. The resulting fragmentation of landscapes and riverscapes threatens biodiversity and can affect dispersal and subsequently, gene flow and genetic health of species. Headwater streams are an integral part of river networks and contribute to biodiversity by providing habitat for temporary and permanent residents, yet they are easily altered and fragmented. The sandhills chub (Semotilus lumbee) is an endemic headwater leuciscid that lives in highly fragmented streams of the sandhills ecoregion in North and South Carolina, USA. New knowledge on the population genetics of the sandhills chub is …

Movement Ecology Of Sandhills Chub, A Carolina Endemic, Zachary Adam Ramsey

Electronic Theses and Dissertations

Fish movement studies have traditionally focused on species that support commercial and recreational fisheries, but recently more focus has been given to non-game, stream fishes because of their recognized importance in maintaining biodiversity within these ecosystems. Stream fish movement is described as being “restricted” and following a leptokurtic distribution via diffusive spread related to environmental and biological factors. Many studies of stream fish movement ecology in North America have occurred in high-gradient streams with coarse substrate in mountains or in streams of the interior plains. Sandhills streams of the southeastern USA are characterized as warm-water, low gradient, and dominated by …

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 …