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Population Abundance And Growth Of Elk (Cervus Canadensis) In Western North Carolina, Jessica Braunstein
Population Abundance And Growth Of Elk (Cervus Canadensis) In Western North Carolina, Jessica Braunstein
Doctoral Dissertations
In an effort to restore extirpated elk to their previous range, 52 elk were reintroduced to Great Smoky Mountains National Park (GRSM) in North Carolina during 2001 and 2002. Since their reintroduction, elk numbers have increased and their range has extended beyond GRSM boundaries. My primary research objectives included estimating population abundance, apparent survival, per capita recruitment, and population growth rate of elk in North Carolina. I used spatially explicit capture-recapture (SECR) models based on fecal DNA to identify individual elk and estimate population abundance and growth in the region. Technicians and I walked a series of transects throughout the …
Communication Distance Predicts Territory Size For An Urban Songbird, Ruth A. Simberloff
Communication Distance Predicts Territory Size For An Urban Songbird, Ruth A. Simberloff
Masters Theses
Many studies demonstrate that urban noise interferes with animal communication by masking acoustic signals such as birdsong, but the functional consequences of impaired communication are still not well understood. Although many bird species sing at higher amplitude in noise pollution, communication distance is still reduced in noisy urban soundscapes. Song is a long-distance signal that functions to attract a mate and defend a territory, so a reduction in communication distance could negatively influence a male’s reproductive or competitive success. Reduced territorial success could manifest as more frequent territorial intrusions, reduced territory quality, or reduced territory size. We examined the relationship …
Are Fungal Endophytes Of Fire Adapted Plants Also Fire Adapted?, Alexander C. Dowd
Are Fungal Endophytes Of Fire Adapted Plants Also Fire Adapted?, Alexander C. Dowd
Chancellor’s Honors Program Projects
No abstract provided.
Brown People, Green Spaces: Colonial Imaginaries And The Whiteness Of Nature, Jeffrey Michael Desalu
Brown People, Green Spaces: Colonial Imaginaries And The Whiteness Of Nature, Jeffrey Michael Desalu
Masters Theses
For several years, conversations about the absence of racial and ethnic diversity in ecology and evolutionary biology (EEB) and the conservation movement have been growing in scope. Critics argue that the overwhelmingly white demography of EEB departments and conservation organizations deprive both of a necessary diversity of perspective and, more importantly, deprive people of color and other minoritized groups of a voice in the study of and advocacy for their lived environments. Here, I situate the current conversations in historical context, arguing that the current lack of diversity is in part a reflection of the material and ideological bases for …
Sphenoidal Sinuses And Spherical Harmonics: Variation And Covariation Of The Most Morphologically Diverse And Least Understood Paranasal Sinus, Katharine Grace Josephine Ryan
Sphenoidal Sinuses And Spherical Harmonics: Variation And Covariation Of The Most Morphologically Diverse And Least Understood Paranasal Sinus, Katharine Grace Josephine Ryan
Doctoral Dissertations
Understanding the shape variation of the human sphenoidal sinus is important to several areas of research. This includes clinical investigation (sinus pathology and safe endoscopic endonasal surgical practice) and paranasal sinus evolution (for which there is still no consensus). Yet, the sphenoidal sinus has high morphological variation, prohibiting its quantification through traditional geometric morphometric landmarking methods. The sphenoid body, and thus also the sinus contained within, is located directly at the developmental center of the basicranium in humans, where the three cranial fossae meet at the midline, and adjacent to the three synchondroses which are the sites of cranial base …
Water Availability As A Cross-Scale Driver Of Microbial Functions And Free Viral Abundance In Soil, Aubrey K. Fine
Water Availability As A Cross-Scale Driver Of Microbial Functions And Free Viral Abundance In Soil, Aubrey K. Fine
Doctoral Dissertations
Viral infection is widespread in natural microbial communities, with extensive study in aquatic ecosystems demonstrating direct influence on host physiology, functional activity, and mortality. While similar dynamics are assumed to occur across ecosystems, soils are distinct microbial habitats where soil physiochemical structure and water availability constrain resource availability. These unique environmental conditions have been widely demonstrated to affect microbial distribution, diversity, and functional activity in bulk soil, while their influence on virus-microbe interactions and free viral abundance remains limited. To address this knowledge gap, this research had three broad aims: i) to investigate variability in microbial responses to drying-rewetting cycles …
The Influence Of Traits On Species Responses To Climate Change: Does Warming Negatively Impact Native Species More Than Invasive Species?, Margaret Anne Mamantov
The Influence Of Traits On Species Responses To Climate Change: Does Warming Negatively Impact Native Species More Than Invasive Species?, Margaret Anne Mamantov
Doctoral Dissertations
Current climate change is increasing global temperatures so that many organisms are now experiencing temperatures outside of their thermal tolerance, which threatens their survival. Organisms respond to physiologically stressful temperatures to reduce this threat. Organisms respond to warming through three main mechanisms: range shifts, adjustments via phenotypic plasticity, and evolutionary adaptation. Organisms vary in their ability to utilize these three mechanisms, leading to differences in the magnitude and success of their adjustments to temperature change. Here, I examine how organismal traits influence variation in species response to climate change. Chapter one addresses how physiological tolerance may influence the rate of …
Evaluating Current And Future Potential Distribution Of Epiphytic Orchids In The Congo Basin With Ecological Niche Models, Michael L. Ngoh
Evaluating Current And Future Potential Distribution Of Epiphytic Orchids In The Congo Basin With Ecological Niche Models, Michael L. Ngoh
Masters Theses
The Congo Basin Forest harbors a rich diversity of epiphytic communities, with the Orchidaceae alone making up more than 50% of all epiphytes in the region. Despite the huge diversity of epiphytes, many species, including epiphytic orchids, are at risk to a diverse array of threats. Climate change for instance poses severe threats to epiphytic orchids due to elevated temperatures, prolonged periods of droughts, as well as reduced rainfall across the Congo Basin Forest. In this study, we used ecological niche modeling and GIS techniques to identify spatial patterns of species richness, potential future climate refugia, and novel climatic suitability …
Broadscale Outcome And Monitoring Assessment To Evaluate Protected Area Effectiveness In Northern Patagonia, Maria Daniela Rivarola
Broadscale Outcome And Monitoring Assessment To Evaluate Protected Area Effectiveness In Northern Patagonia, Maria Daniela Rivarola
Doctoral Dissertations
Biomes worldwide have been affected by biodiversity loss and habitat degradation for more than a century. Protected Areas (PAs) have been established in almost every country, as they represent one of the most important tools in biodiversity conservation. Nevertheless, the relentless biodiversity loss trend has not stopped. Concern about PA effectiveness has risen, and several methods to evaluate it have been implemented over the last few decades. Nahuel Huapi National Park (NHNP) is the first PA in Argentina and one of the largest. The area is considered a biodiversity hotspot, and its conservation is essential, as unique ecological and evolutionary …
Making Sense Of Soil Microbiome Complexity For Plant And Ecosystem Function In A Changing World, Kendall K. Beals
Making Sense Of Soil Microbiome Complexity For Plant And Ecosystem Function In A Changing World, Kendall K. Beals
Doctoral Dissertations
Soils contain the highest biodiversity on Earth. While the importance of the soil microbiome for larger-scale ecological phenomena such as nutrient and carbon cycling, plant growth and plant community dynamics is well-established, the fundamental question of the ecological and evolutionary function of this immense belowground microbial diversity for plant and ecosystem function still remains a great challenge in microbial ecology research. The objective of this dissertation is to understand how the importance of soil microbial community composition for plant and ecosystem function and how changes to soil microbial community composition from climate change-induced disturbance events, specifically fire, influence plant and …
Elk Abundance, Survival, And Health In The Cumberland Mountains Of Tennessee, Katherine Kurth
Elk Abundance, Survival, And Health In The Cumberland Mountains Of Tennessee, Katherine Kurth
Doctoral Dissertations
Managing sustainable wildlife populations requires insight into population abundance and health. Since reintroduction, elk (Cervus canadensis) at the North Cumberland Wildlife Management Area (NCWMA) in Tennessee have shown marginal population growth using low-precision abundance estimates. Limited research investigating possible population limiting factors has occurred since evaluations conducted directly after translocation. To provide information necessary for effective population management, we estimated abundance, identified survival rates, and conducted mortality and health surveillance. Precise abundance estimates of eastern elk populations are challenging to obtain using traditional capture-recapture due to invasive handling of individuals and low detection in forested landscapes. Therefore, we …
Climate-Driven Selection Results In Powerful Geographic Framework For Predicting Phenotype, Alexandra Neild
Climate-Driven Selection Results In Powerful Geographic Framework For Predicting Phenotype, Alexandra Neild
Masters Theses
Our ability to prepare for and mitigate the likely ecological and evolutionary impacts of climate change largely depends upon our ability to predict the phenotypic responses of organisms that allow them to persist, adapt, and migrate along environmental stress gradients. Using fifteen populations of cottonwoods, a dominant riparian forest tree, that are distributed along elevation gradients and represent three genetic provenances, we hypothesized and show that: 1) populations within a provenance demonstrate parallel evolutionary responses to climatic gradients associated with elevation; and 2) the evolutionary effects of elevation on bud-break phenology varied by provenance. Across all populations, we find strong …
Plant Community Responses To Interactive Anthropogenic Disturbances Along A Natural-Wildland-Urban Gradient And Undergraduate Students’ Attitudes Toward Disturbances, Mali M. Hubert
Doctoral Dissertations
Anthropogenic disturbances are defined as any change caused by human activity that alters biodiversity. Wildfire and urbanization disturbances are among the most influential on the landscape because of their individual and interactive properties. Areas deemed wildland-urban interfaces (WUI; area where environment intermingles with human-built structures) are increasing near protected lands because of human population growth and movement, which often facilitates fire ignitions by humans. Houses that are adjacent to or overlap with wildland vegetation can complicate protection of urban development and wildlands from fires. The expansion of the WUI due to population growth will exacerbate fire risk, which can ultimately …
Microplastics Exposure In At-Risk Myotis Lucifugus Bats Of The Northeastern United States, Leah Crowley
Microplastics Exposure In At-Risk Myotis Lucifugus Bats Of The Northeastern United States, Leah Crowley
Chancellor’s Honors Program Projects
No abstract provided.
Plant Neighbor Interactions Of A Native Goldenrod Impact Abundance And Composition Of Pollinator Communities, Emma P. Kruse
Plant Neighbor Interactions Of A Native Goldenrod Impact Abundance And Composition Of Pollinator Communities, Emma P. Kruse
Chancellor’s Honors Program Projects
No abstract provided.
A Systematic And Biogeographic Study Of Trillium (Melanthiaceae), Jayne A. Lampley
A Systematic And Biogeographic Study Of Trillium (Melanthiaceae), Jayne A. Lampley
Doctoral Dissertations
Trillium (Melanthiaceae, Parideae) has a disjunct distribution occurring in eastern and western North America, and eastern Asia. Past studies have examined the phylogeny and historical biogeography of Melanthiaceae and Parideae, however these studies either did not fully examine these aspects within Trillium or did not employ sufficiently broad taxonomic or character sampling to clarify relationships among taxa. The first phylogenetic analysis presented in this study provides a resolved phylogeny for Trillium s.l. and Paris s.l. by using a dataset of 70 plastid coding genes and by sampling broadly from Trillium s.s., Pseudotrillium, Trillidium, Paris s.s., Daiswa, and Kinugasa. The results …
Geographic Patterns Of Genetic Diversity Under Climate Change: Linking Genes And Ecosystems, Shannon L. Bayliss
Geographic Patterns Of Genetic Diversity Under Climate Change: Linking Genes And Ecosystems, Shannon L. Bayliss
Doctoral Dissertations
Climate change is having profound effects on species distributions. However, much less is understood about how climate change may alter the distribution of genetic variation within species across landscapes. Maintaining genetic diversity within populations is essential for the survival of species in the face of rapid climatic changes, but importantly, losses of genetic variation will also have significant consequences on entire ecosystems. The objective of this dissertation is to understand how genetic variation in a riparian cottonwood species, Populus angustifolia, affects mass and energy exchange between the land and atmosphere across ~1700 km of latitude of the western United …
Microbial Community Dynamics Of A Microcystis Bloom, Helena Pound
Microbial Community Dynamics Of A Microcystis Bloom, Helena Pound
Doctoral Dissertations
Harmful algal bloom events are notoriously associated with massive economic and environmental consequences, causing wildlife and human health risks. As these blooms increase in occurrence, duration, and severity around the world, it is essential to understand conditions leading to bloom formation and why they persist. Abiotic factors such as nutrients are commonly considered in bloom dynamics, but biotic interactions with co-occurring microbial species and viruses must also be taken into account. Harmful algal blooms dominated by the cyanobacterial genus Microcystis occur in bodies of water around the world and provide an ideal system in which to study top-down controls on …
Impacts Of Anthropogenic Change On Plant Reproduction And Fitness, Alexandra S. Faidiga
Impacts Of Anthropogenic Change On Plant Reproduction And Fitness, Alexandra S. Faidiga
Masters Theses
Humans are altering natural systems around the globe in myriad ways. For plant species, such anthropogenic changes have resulted in increasingly fragmented populations, desynchronized interactions with mutualists, and shifted geographic ranges, among other effects. However, despite numerous examples of human impacts on plant populations, the consequences of these changes on plant reproduction remain poorly understood. In my thesis, I investigate the impacts of two forms of anthropogenic change–habitat disturbance and climate warming–on plant reproduction and fitness. I take two distinct approaches to address questions posed at local and regional scales. In Chapter I, I ask how inbreeding depression varies across …
Seasonality, Distribution, And Biological Control Of Crapemyrtle Bark Scale, A New Invasive Threat In Tennessee, Amira Cornish
Seasonality, Distribution, And Biological Control Of Crapemyrtle Bark Scale, A New Invasive Threat In Tennessee, Amira Cornish
Masters Theses
Crapemyrtle bark scale, Acanthococcus (= Eriococcus) lagerstroemiae (Kuwana), an invasive pest from Asia, is a threat in the United States. to crape myrtles grown in ornamental nurseries and in landscapes. Although mortality to crape myrtles is rare, its negative effects on aesthetics is considerable. It should affect the sale (valued at >$66 million wholesale) and use of crape myrtle in landscapes. This pest species has been found in numerous states, including Tennessee, where little is known about its state-wide distribution, lifecycle, biology, natural enemies, and impact on crape myrtles. The purpose of this two-year study is to gain additional knowledge …
Pollinator Community Homogenization And Pollination Services In Agroecosystems, Devon S. Eldridge .
Pollinator Community Homogenization And Pollination Services In Agroecosystems, Devon S. Eldridge .
Masters Theses
Pollination, or the transfer of pollen to plant stigmas, is an essential part of plant reproduction. The term “pollination system” refers to the floral phenotype and pollinator of a given plant. Although angiosperms exhibit a variety of different pollination systems, most rely partially or completely on animals, particularly insects, to vector their pollen. In agricultural systems, understanding the pollination system of the crop species is necessary to produce an economically valuable yield. Moreover, agricultural management may affect pollination systems by altering the abundance, diversity, or function of the pollinator community. In natural ecosystems, there is a great diversity of pollinating …
Supplementing East Tennessee Landscapes For Pollinators With Native Perennials, Amani Khalil
Supplementing East Tennessee Landscapes For Pollinators With Native Perennials, Amani Khalil
Masters Theses
Tennessee, home to the Great Smoky Mountains, is a biodiversity hotspot for many plant and animal species, yet it receives relatively few conservation dollars (Jenkins et al., 2015). As a biodiversity hotspot, this region may be home to many endemic species, but little is known about the abundance or diversity of insect pollinators. In order to both estimate pollinator communities in East Tennessee and pollinator forage preferences for native Tennessee plants, we established four plots, comprised of three plant families across five common land use types. Over two field seasons we collected nearly 7,300 insect specimens with a total sampling …
Evaluating The Winter Diet Of A Reintroduced Herd Of Elk In The Cumberland Mountains, Tennessee, Using Next-Generation Sequencing Techniques, Dailee L. Metts
Evaluating The Winter Diet Of A Reintroduced Herd Of Elk In The Cumberland Mountains, Tennessee, Using Next-Generation Sequencing Techniques, Dailee L. Metts
Masters Theses
A distinct subspecies of elk (Cervus canadensis), the North American elk (C. canadensis canadensis), once inhabited portions of the southeastern United States, including Tennessee, until their extirpation in the mid 1800s. From 2000 to 2008, 201 Manitoban elk were reintroduced on the North Cumberland Wildlife Management Area (NCWMA). A year-long food habits study using histological analysis of plant material from feces was completed for the NCWMA elk from 2003 to 2004 and has since aided managers in their landscape planning. Since then, more elk have been released onto the area, food plots have been established throughout …
The Hidden Life Of Tropical Roots: Functional Root Traits And Their Response To Climatic Disturbances, Daniela Yaffar
The Hidden Life Of Tropical Roots: Functional Root Traits And Their Response To Climatic Disturbances, Daniela Yaffar
Doctoral Dissertations
Roots play a critical role in plant nutrition, and terrestrial carbon cycling. However, they are often understudied compared to their aboveground counterparts; especially in the tropics, where more carbon is cycled than in any other ecosystem. Some tropical forests, like in Puerto Rico, are more represented in scientific studies than others. However, this information is sparse, complicating the interpretation of root trait patterns. Trees in Puerto Rico have adapted mechanisms for withstanding hurricane disturbances, including in their roots. Additionally, as many tropical forests, some in Puerto Rico have low available phosphorus (P); thus, trees rely on root traits to enhance …
Evolution And Resurrection Ecology Of A Foundational Coastal Marsh Plant, Jennifer L. Summers
Evolution And Resurrection Ecology Of A Foundational Coastal Marsh Plant, Jennifer L. Summers
Doctoral Dissertations
Stratified storage of dormant seeds in soil can result in natural archives useful for studying evolutionary responses to environmental change. However, few studies leverage soil-stored seed banks as natural archives, in part because of concerns over attrition, bias, and sediment mixing. Here, I examine the persistent seed bank of Schoenoplectus americanus, a foundational brackish marsh sedge, to a) determine whether it can serve as a resource for reconstructing demographic and population genetic/genomic variation, b) whether and how evolution may be occurring across a century. After extracting seeds from radionuclide-dated soil cores taken across the Chesapeake Bay, I “resurrected” age …
Applications Of Comparative Genomics And Data Science To Agricultural And Clinical Research, Katrina A. Schlum
Applications Of Comparative Genomics And Data Science To Agricultural And Clinical Research, Katrina A. Schlum
Doctoral Dissertations
The advent of inexpensive, high-throughput whole genome sequencing (WGS) technologies has led to the generation of thousands of related genomes, even from a single study. Large-scale genome analysis has resulted in hypothesis-generating approaches in the fields of clinical, human and agriculture genomics. Additionally, population-level genomic sampling has resulted in a decrease in false positives in genotype-phenotype associations and an increase in understanding of the basis of disease, antibiotic and pesticide resistance. Deeper understanding of migration, genetic divergence and evolution has also been made possible due to WGS. This research applies comparative genomics, population genomics and data science approaches to whole …
The Effects Of High Temperatures On Mating Communication In Songbirds, Casey Marie Coomes
The Effects Of High Temperatures On Mating Communication In Songbirds, Casey Marie Coomes
Doctoral Dissertations
Due to climate change, animals around the globe are experiencing the negative impacts of hot temperature extremes. Hot temperatures can affect animals is by inducing behavioral changes. Some of these behavioral changes include reductions in important, fitness-related behaviors such as foraging and mating. One aspect of mating behaviors that high temperatures can impact is communication. In many systems, mating communication consists of a male signaler transmitting a signal to a female receiver, who then uses the signal to assess the male’s quality as a potential mate. High temperatures can impact this process at the level of the signaler, the receiver, …
The Effects Of Urbanization On The Avian Gut Microbiome, Mae Berlow
The Effects Of Urbanization On The Avian Gut Microbiome, Mae Berlow
Doctoral Dissertations
The gut microbiome influences and is influenced by the host, and can affect the host organism by contributing to health, development and immunity. Similarly, the host can influence this community; it’s makeup can vary with host species, locality, diet, social stressors, and environmental stressors. Some of these environmental stressors have arisen due to human-induced rapid environmental change, like urbanization. The physiology and behaviors of organisms that are able to persist in urban environments are often different from their non-urban congeners. Nutrition, development, and immunity—all of which are affected by the gut microbiome—are important factors that can determine survival in urban …
Social Context Influences On Behavior Of Carolina Chickadees, Brittany A. Coppinger
Social Context Influences On Behavior Of Carolina Chickadees, Brittany A. Coppinger
Doctoral Dissertations
This dissertation assesses fundamental social factors that drive variation in calling and other behaviors of experimental flocks of Carolina chickadees. Specifically, I tested how group member familiarity and group composition affected individual behavior. In addition, I performed a direct experimental test of the Social Complexity Hypothesis for Communicative Complexity, which states that groups that are more socially complex will communicate with greater signal complexity than groups that are less social complex. I consider complexity to be a combination of three factors: the number of parts in a system, the variation among the parts, and the variation in the way those …
Life History, Diet And Habitat Of The Federally Endangered Laurel Dace (Chrosomus Saylori), Shawna M. Fix
Life History, Diet And Habitat Of The Federally Endangered Laurel Dace (Chrosomus Saylori), Shawna M. Fix
Masters Theses
Laurel Dace (Chrosomus saylori) is a small, freshwater minnow that is endemic to headwater streams on Walden Ridge, Tennessee. The species was listed as federally endangered in 2011 and the U.S. Fish and Wildlife Service Recovery Plan indicates a need for life history, diet and habitat studies. A literature review, samples of archived specimens, and a surrogate species, the Tennessee Dace (Chrosomus tennesseensis), were used to describe the life history and diet of the Laurel Dace. A total of 370 Tennessee Dace were collected from Laurel Ford Branch, a stream 8.6 km from the Laurel Dace …