Ecology and Evolutionary Biology Commons^™

Bugs, Birds, Blue: Queer Ecologies Of Embodiment, Kinship, And Survival, Celeste B. Newcomb

Theses and Dissertations

bugs, birds, blue is a multi-channel audiovisual installation that examines queer ecology as a framework for understanding transgender embodiment, kinship, and survival amid environmental crisis and ongoing political attacks on trans life (Mortimer-Sandilands and Erickson). Through sculpture, projection, sound, reflective surfaces, and biological imagery, the installation places human bodily matter alongside microbial and aquatic life forms to challenge narratives that frame trans existence as unnatural, recent, or isolated. Instead, the work proposes transness as relational, adaptive, and deeply entangled with broader ecological systems. The installation is composed of two interconnected environments. On one side of the space, three aquariums rest …

Degradation And Metabolic Analysis Of Synthesized Quorum-Sensing Signals By The Model Eukaryote Chlamydomonas Reinhardtii, Adam Josef Bach

Theses and Dissertations

Bacterial organisms can “talk” with one another on a colony-wide scale using a communication system known as quorum-sensing (QS) via chemical signals. These signals are produced at a basal rate throughout the life of the bacteria and are classified as autoinducers, which diffuse across the cell membrane. Once the critical concentration is reached, they begin to diffuse back into the cell and initiate a phenotypic change. As these signals exist outside the membrane of their producer, they are also accessible to other organisms. It has already been noted that some plant species uptake these compounds through their roots and break …

Jackfruit Peel Valorization Through An Integrated Biorefinery Approach, Rohil Kumar K Mr

Theses and Dissertations

Jackfruit (Artocarpus heterophyllus) peel (JFP), an abundantly available lignocellulosic biomass, remains largely underutilized despite being rich in cellulose, hemicellulose, lignin, and pectin. In India, approximately 13,460 hectares are under jackfruit cultivation, with Panruti in Tamil Nadu as a major production zone. The discarded peel often contributes to environmental pollution and greenhouse gas emissions. The present study emphasizes sustainable valorization of JFP through an integrated biorefinery framework for generating value-added bioproducts.

Major biopolymers, cellulose, hemicellulose, lignin, and pectin were extracted and fractionated, followed by detailed physicochemical characterization using FTIR, NMR, XRD, SEM, TGA, DSC, GPC, and BET analyses. Pectin extraction with …

The Role Of Exotic Plants In The Diet Of Black-And-White Colobus Monkeys (Colobus Guereza) In Kibale National Park, Uganda, Michelle Gaykov

Theses and Dissertations

Exotic plants have both positive and negative impacts on their environment. They may act as additional food sources for the local fauna or as competition for local flora or leading to changes within a landscape or ecosystem. To considere the role of exotics in primate diet, this study focused on the dietary role of exotic plant species in the diet of a leaf-eating foregut fermenting monkey, the black-and-white colobus monkeys (Colobus guereza) in Kibale National Park, Uganda. Int this study, I followed individuals in two groups of black-and-white colobus monkeys for 21 days recording their food intake (0700-1900). I also …

Machine Learning-Based Spatio-Temporal Modeling Of Climate Dynamics And Desertification In The Sahara–Sahel Region, Stephen M. Tivenan

Theses and Dissertations

Arid climate classifications are threshold-dependent and easily interpretable mappings that are widely used in ecological, agricultural, and climate-related studies. These classifications inform scientific understanding, support policy and land management decisions, and provide an intuitive summary of environmental conditions. Despite their usefulness, traditional arid climate classifications often fail to quantify uncertainty, incorporate spatial context, or account for complex relationships among relevant environmental variables. Existing approaches to uncertainty assessment have largely relied on comparing classifications across multiple datasets or alternative formulas, but these methods generally overlook important spatial dependence and latent structure in the data.

This dissertation develops three machine learning-based statistical …

Climate, Biogeography, And Dispersal: A Unifying Framework For Ameri-Caribbean Dry Forests, Pablo Lopez Bustamante

Theses and Dissertations

Seed dispersal is a crucial ecological function that enables plants to alter their distributional range, avoid intense competition and natural enemies near the parent plant, and recover from disturbances. These processes shape species and functional composition of forests. Wind has traditionally been considered the dominant dispersal mechanism in Ameri-Caribbean dry forests, yet growing evidence suggests that other dispersal mechanisms also play significant roles in this ecosystem, responding differently to biotic and abiotic conditions. Still, how dispersal syndrome composition influences plant communities, the ecological drivers underlying these patterns, and the effects of climate change on dispersal syndrome dominance remain poorly understood. …

Sex In Plants: Birth, Death, And Trying To Survive In Changing Climates, Elena M. Meyer

Theses and Dissertations

Plant mating systems are key determinants of fitness. Angiosperms exhibit a wide variety of reproductive strategies, including self-fertilization (or selfing), outcrossing, and mixed mating. It has been estimated that up to 43% of plant species are capable of selfing, and selfing has been hypothesized to provide reproductive assurance where opportunities for mating may be limited, such as in marginal environments. However, questions regarding the overall distribution of selfing rates across angiosperms, the maintenance of mixed mating in the face of inbreeding depression, and the impact of self-fertilization on diversification rates remain incompletely resolved. Here, we explore the dynamics of self-fertilization …

Managing Multi-Drug Resistance: An Evolutionary Game Theory And Optimal Control Approach, Shukhrat Nasrulloev

Theses and Dissertations

Multi-drug resistance is an evolutionary process in which treatment eliminates sensitive cells, allowing resistant clones to dominate. This thesis investigates this process using a framework integrating population dynamics, evolutionary game theory, and optimal control theory. We develop a two-population logistic growth model describing competition between drug-sensitive and drug-resistant cells under treatment, construct dose-dependent payoff matrices and replicator dynamics to characterize evolutionary competition, and derive a critical drug level D_crit = (r_S - rR)/(dS - d_R) at which resistant cells gain a fitness advantage. An optimal control problem is formulated via Pontryagin's Maximum Principle to identify schedules …

Interactive Effects Of Bti Larviciding And Predation On Culex Pipiens And Its Ephemeral Pond Communities, Jaclyn S. Everly

Theses and Dissertations

Populations of adult vector mosquitoes can be controlled by reducing larval mosquito abundances in aquatic habitats. This can be achieved via predation by introduced or naturally-occurring enemies (i.e., biocontrol or conservation control) or by applying pesticides to larval mosquito habitats (i.e., larviciding). The larvicide Bacillus thuringiensis israelensis (Bti) is commonly applied to ephemeral ponds to control populations of Culex pipiens mosquitoes that vector West Nile virus. However, there is concern that Bti may directly or indirectly harm non-target organisms such as dragonfly and damselfly naiads, which provide a natural source of mosquito biocontrol. Bti or predators may also induce positive …

Arthropod Communities Associated With Endangered Physaria Thamnophila (Zapata Bladderpod) And Its Nurse Plants, Cesar Adrian Hinojosa

Theses and Dissertations

Physaria thamnophila is a federally endangered plant whose associated arthropods are understudied and poorly understood. This study surveyed environmental conditions and the arthropod community within the Arroyo Ramirez Tract of the Lower Rio Grande Valley National Wildlife Refuge, assessed which environmental factors influenced the arthropod community, and sought arthropod taxa statistically associated with Physaria thamnophila. Sticky cards and pitfall traps were deployed for a 7 day period, and vacuum samplings occurred quarterly over the span of a year to collect arthropods that were identified to order and family level for Coleoptera, Hymenoptera, and Lepidoptera. Biotic and abiotic surveys were performed …

Determination Of An Effective Natural Boxelder Bug (Boisea Trivittata) Repellent, Reyna Chavez

Theses and Dissertations

This study investigates the use of ecofriendly repellant alternatives to pest management to control boxelder bugs (Boisea trivittata). This bug gathers by the thousands on warm surfaces of exterior suburban homes during early fall and late spring. I determined bug repellency to turmeric oil (Curcuma longa), catnip (Nepeta cataria), citronella (Cymbopogon nardus), and lavender (Lavandula angustifolia). The treatments consisted of essential oils containing 20% methanol. All treatments demonstrated repellency of Boxelder bugs. Citronella was the most effective and had the highest level of repellency range of 90-99%. Catnip was the least effective with a repellency range of 63-82%.

Seagrass Preference Among Pinfish In The Lower Laguna Madre, Nathaniel Garza

Theses and Dissertations

Pinfish (Lagodon rhomboides) is a common estuarine fish species found from Massachusetts to the Yucatan, Mexico. As juveniles, pinfish spend a significant portion of their life in coastal seagrasses which provide both shelter from predators and food. Along the Texas coast, there are three major species of seagrass- turtle grass (Thalassia testudinum), manatee grass (Syringodium filiforme) and shoal grass (Halodule wrightii) that differ in structural complexity. The goal of this study was to determine if pinfish associate more with one seagrass species than the others. A year-long field study was completed using twelve sample sites in the Lower Laguna Madre, …

Chemically Mediated Communication In Mound-Building Termites, Sree Subha Ramaswamy

Theses and Dissertations

Nest-building in social insects requires layered communication to coordinate complex, functional structures for housing, protection, storage, and homeostasis. This is especially striking in mound-building termites, which construct and repair large mounds collectively despite lacking image-forming eyes. This thesis investigates how Odontotermes obesus achieves such coordination through chemical communication embedded in soil.

Using controlled two-choice assays with manipulated soils, I separated airborne volatile signals from contact non-volatile signals by baking to remove volatiles, a mesh assay that presented volatile cues without contact, and solvent extraction with reapplication of contact cues. I quantified responses in major-only, minor-only, and mixed groups at two …

Assessment Of Floral Resources From Three Tamaulipan Thornscrub Communities Of The Lower Rio Grande Valley, Gracie Makenna Granados

Theses and Dissertations

The Tamaulipan thornscrub is a transition zone between the neotropics and the temperate regions, harboring high biodiversity. This habitat supports a diverse insect community, including many pollinators of native and cultivated plants in Texas and northeastern Mexico. This ecosystem has been extensively degraded and lost; only 5% of its original cover remains north of the Rio Grande. Restoration of the Tamaulipan thornscrub has been ongoing for over three decades, but the important roles of pollinators in the success of such efforts and the functioning of the restored ecosystem have rarely been considered in restoration efforts. The purpose of this study …

Patterns Of Fire History And Vegetation Changes In The Last 5000 Years: A Paleoecological Study Of Iquitos, Annabel Zwarts

Theses and Dissertations

The vegetation of the Amazonian rainforest is hypothesized to have been shaped by pre-Columbian activities, such as burning and palm management to various extents. Management of palms is hypothesized to have caused some of the most useful species to become hyperdominant in Amazonia. This study investigated the extent to which human activities over the past 5000 years affected palm abundances in mature lowland rainforests near Iquitos, Peru. I used phytoliths and charcoal from soil cores to determine the history of local floras, and modern palm surveys to compare modern phytolith occurrence with modern vegetation. Because pre-Columbian activity clustered along the …

Social Networks And Behavioral Adaptation Of Serrano Horses In A Rewilding Initiative In Spain, Ashley Bruno

Theses and Dissertations

Rewilding is a conservation measure that involves actively relocating species or restricting human land use to improve ecosystem sustainability. However, critics raise concerns that rewilding privileges ecosystem function over endangered species. Due to a lack of monitoring around species’ relocations, uncertainty lies in ecological outcomes and psychological, social, cultural impacts on affected animals. For this project, we collaborated with the non-profit Rewilding Europe that sought to conserve Serrano horses (Equus caballus), an ancient and under-studied breed of Spanish horse by relocating 11 individuals to a protected site in Guadalajara, Spain in June 2022. Our research aimed to address …

Diversification Of Avifauna In The Darién Highland Region: Ecological Niche Modeling, Phylogeography And Morphology To Explore Speciation In The Montane Species Myadestes Coloratus, Chlorospingus Tacarcunae And Margarornis Bellulus., Jorge L. Garzon Vasquez Mrs

Theses and Dissertations

Montane regions in the Neotropics are hotspots of endemism and biodiversity, yet their species are especially vulnerable to the impacts of climate change and geographic isolation. This thesis investigates the evolutionary and ecological dynamics of three bird species endemic to the Darién Highlands of eastern Panama: Myadestes coloratus, Chlorospingus tacarcunae, and Margarornis bellulus. Through an integrative approach combining ecological niche modeling, morphometric analysis, and genomic data from ultraconserved elements (UCEs) and mitochondrial DNA, the study explores the historical biogeography, current distribution patterns, population structure, and phenotypic differentiation of these montane taxa. Ecological niche models revealed that suitable habitat …

Physiological Responses And Plant Trait Interactions With Coastal Dune And Swale Development, Emily C. Riffe

Theses and Dissertations

Vegetation is crucial to coastal ecosystems experiencing climate change and storm-induced disturbance. Plant species interact with the physical environment and are considered “ecosystem engineers.” Sand dunes and barrier islands are at the forefront of climate change impacts as they are barriers that protect landward habitat and communities. Nature based solutions are utilized to protect infrastructure on developed coastlines. Understanding how dominant plant species interact with and alter the physical environment enhances our understanding of the mechanisms of change and consequences to the system. The goal of this research was to quantify physiological and functional trait differences in dominant species found …

Karyotyping As A Method To Verify Phylogenetic Relationships Among The Enneacanthus Species, Ophelia A. Anderson

Theses and Dissertations

The Enneacanthus genus consists of three species of freshwater fish endemic to eastern North America: E. obesus (Banded Sunfish), E. gloriosus (Blue Spotted Sunfish), and E. chaetodon (Black Banded Sunfish). Previous studies using molecular data suggest that E. obesus and E. gloriosus are more closely related, with E. chaetodon as the most distantly related species in the genus. This study investigates the phylogenetic relationship among the Enneacanthus species, using karyotype characteristics - chromosome number, morphology and fundamental number - as comparative metrics. Chromosome spreads were obtained from scale and gill epithelium samples collected between 1993 and 1994. Prepared slides …

Bugs In The Flux: Links Between Arthropod Diversity And Spatial Variation Of Soil Respiration In A Temperate Forest, Erin-Darby H. Mcclain

Theses and Dissertations

Soil respiration (Rs) is the largest terrestrial flux of carbon (C) to the atmosphere, with heterotrophic contributions to Rs varying spatially and temporally. While microbes are the primary and most thoroughly studied source of soil heterotrophic respiration (Rh), contributions from higher trophic organisms, including arthropods, are rarely quantified and poorly understood. Arthropod abundance and diversity correspond with variation in soil microclimate, which is influenced by site factors including canopy structure, site productivity, and disturbance. However, the extent to which these site factors influence arthropod abundance and diversity, and consequently, spatial variation in Rs is not known. The objective of our …

Linking Disturbance & Macrophyte Colonization–Extinction Dynamics To Invasion Success & Community Assembly: Integrating Population, Community, & Landscape Perspectives, Joshua T. Armstrong

Theses and Dissertations

Aquatic plants, macrophytes, are foundational components of freshwater ecosystems, influencing abiotic conditions, providing habitat structure, and shaping biodiversity and community assembly processes. Their role is particularly critical in dynamic systems where disturbance regimes and colonization processes interact to shape community patterns and species distributions. Despite their ecological importance, macrophytes remain underrepresented in theoretical and applied studies of metacommunity dynamics and invasion ecology, especially in natural systems experiencing frequent environmental fluctuations. Here we aim to elucidate how macrophytes influence and respond to spatial and temporal variation in aquatic ecosystems, with a particular focus on colonization-extinction dynamics, invasion success, and community assembly. …

Climate Change-Induced Shifts In Mediterranean Fungal Fruiting Phenology And Productivity, Rachel Demay

Theses and Dissertations

We used a 29-year dataset of mushroom fruiting from the Pinar Grande forest in northern Spain to investigate the effects of climate change on the phenology, productivity, and diversity of mycorrhizal and saprotrophic mushrooms. We investigated the long-term trends in fruiting season length, yield (by count, total weight, and average weight), and genus richness. Additionally, we identified associations between monthly temperature and monthly precipitation with these fungal responses across functional groups: mycorrhizal, saprotrophic, litter-decaying saprotrophic, and wood-decaying saprotrophic mushrooms, and the economically-important edible genera Boletus and Lactarius. We found that autumnal season length in the Pinar Grande has shortened over …

Survey And Comparative Analysis Of Pollinator Diversity, Abundance, And Foraging Activity Of Diptera And Hymenoptera In Selected Habitats Of South Texas, Melissa Villarreal

Theses and Dissertations

With the declining bee population, non-bee pollinators can serve as an alternative source for pollination. Diptera is a potential source of untapped pollinator resources based on their abundance and visitation rate, but they are understudied in the field of pollination ecology. This study aimed to characterize the pollinator community in selected areas of South Texas. It focused on the Diptera and Hymenoptera families to compare their diversity, relative abundance, foraging behaviors, environmental influences, and vegetation associations. Active sampling and line transect were used in the survey to sample the Hymenoptera and Diptera communities to their family taxonomic rank. Statistical analyses …

Survey And Comparative Analysis Of Pollinator Diversity, Abundance, And Foraging Activity Of Diptera And Hymenoptera In Selected Habitats Of South Texas, Melissa Villarreal

Theses and Dissertations

With the declining bee population, non-bee pollinators can serve as an alternative source for pollination. Diptera is a potential source of untapped pollinator resources based on their abundance and visitation rate, but they are understudied in the field of pollination ecology. This study aimed to characterize the pollinator community in selected areas of South Texas. It focused on the Diptera and Hymenoptera families to compare their diversity, relative abundance, foraging behaviors, environmental influences, and vegetation associations. Active sampling and line transect were used in the survey to sample the Hymenoptera and Diptera communities to their family taxonomic rank. Statistical analyses …

The Influence Of Wind Energy Development On Occupancy Of Medium And Large-Sized Mammals In South Texas, Elwynn Sherman

Theses and Dissertations

Conservation paradigms have shifted from single to multi-species approaches for assessing and conserving mammalian populations and the habitats that they occupy. The effect of wind turbine development is an important anthropogenic change to study due to the increasing demand for wind energy in Texas. In this study, I gathered remote camera trap data on medium and large-sized mammal populations in south Texas Tamaulipan thornscrub habitat. The objectives were to determine species presence, the effect of habitat characteristics and anthropogenic disturbances on species occupancy, and the effect of temperature on species detection. The results showed that distance from wind turbines did …

Assessing The Influence Of Native And Invasive Grasses On The Behavior Of Aedes Aegypti In South Texas, Emily Medelez

Theses and Dissertations

Invasive grasses in South Texas can have widespread negative effects, displacing native species, reducing biodiversity, and posing risks to public health. These grasses may flourish in moist, shaded environments, which not only support their growth but also creates habitats favorable for mosquito activity. This can increase the population and alter the behavior of mosquitoes, potentially raising the risk of disease transmission. In this thesis, I look at the behavior of mosquito species Aedes aegypti, primary vector of the yellow fever virus. I analyzed the influence of oviposition, flight and resting behaviors. I tested the relative attraction of Aedes mosquitoes …

Investigation Of Reproductive Inhibition During Chronic Heat Stress In C. Elegans, Macy Makenna Nielander

Theses and Dissertations

Nearly all organisms experience heterogeneity in environmental conditions that can negatively impact fitness. A common adaptive strategy to reduce the impact of this stress is called facultative diapause, where development and reproduction are temporarily arrested to promote survival. Facultative diapause is characterized by three major criteria, the arrest must be (i) induced by an unfavorable environmental condition, (ii) reversible, and (iii) driven by genetically regulated mechanisms. The aim of this thesis was to determine whether chronic heat-induced inhibition of egg laying in Caenorhabditis elegans represents a novel form of facultative diapause. It was found that the inhibition of egg-laying is …

The Effects Of People, Time Of Day, And Season On Affiliative And Stereotypic Behaviors In Captive Rhinoptera Bonasus And Other Rays Across Two Human-Interactive Enclosures, Wren C. A. Newman

Theses and Dissertations

Cownose rays (Rhinoptera bonasus) are among the most common species found in aquaria, yet the impact of touch enclosures on their welfare remains largely unknown. While research on animal-visitor interactions has produced mixed results for other species, the lack of studies focusing on fish welfare poses a risk of overlooking potential welfare concerns. Therefore, we aimed to establish a baseline for cownose rays regarding stereotypic behaviors, sociality, and activity in captivity, and to examine the influence of human interaction on these behaviors. We collected over 700 hours of footage from two enclosures at Adventure Aquarium in Camden, NJ …

Fecal Genomics Provides Insights On Connectivity Of Endangered Wildlife In A Human Dominated Landscape, Abhinav Tyagi

Theses and Dissertations

Many mammalian species, facing severe historic range reductions, now inhabit fragmented habitats. Habitat fragmentation involves the reduction of habitat into smaller patches, increasing distances between them, and eventually leading to small isolated populations. Species' responses to habitat alteration may vary based on factors such as body size, dispersal ability, and abundance. Understanding these differences is crucial for effective multispecies conservation planning. Genomic data, within a landscape genetic framework, are increasingly applied to evaluate the effects of habitat fragmentation and understand influential landscape features for connectivity. The quantity of data enhances the power and precision of assessing landscape impacts on gene …

Optimization Of Coral Restoration Along The Florida Reef Tract, Raymond Barry Banister

Theses and Dissertations

Historically, the reefs of Florida were dominated by two framework-building corals, Acropora cervicornis and A. palmata. However, these two populations have declined by 95% since the 1970s. The predominant contributors to the coral decline have been ocean warming and disease. In response to the decline, restoration organizations were established to improve survival, growth, and reproduction. Yet, there are gaps in current restoration practices and our knowledge of effective restoration techniques. This study uses large datasets to develop models that predict the most optimal locations for coral restoration in Florida and examines the relationships between the occurrence of wild acroporids …