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A Genetic Analysis Of The Rare Endemic Astragalus Ripleyi Barneby, Juan Antonio Jaramillo-Chico

Master's Theses

Astragalus ripleyi Barneby is a rare endemic species found in the San Luis Valley of the southern portions of the Rocky Mountains in Colorado and New Mexico. Though not federally listed as endangered, the species is on the Bureau of Land Management’s Sensitive Species List, warranting protection and continued management. This study aims to provide information about the genetic health of the species to inform conservation efforts and provide updated management recommendations. A genetic health analysis was conducted investigating the levels of diversity present in the species, how genetic diversity is structured across the known range of the species and …

Hidden Diversity In A Clonal Endemic: Insights Into Clematis Socialis From A Population Genetics Perspective, Joanna M. Lapoint

Theses

Clematis socialis (Kral) is a rare, federally endangered perennial species restricted to a small number of fragmented populations in Alabama and Georgia. The species exhibits extensive clonality and limited sexual recruitment, characteristics that complicate expectations regarding genetic diversity and population connectivity. Despite its conservation significance, genome-wide assessments of population structure have been lacking. We used genotyping-by-sequencing (GBS) to generate a genome-wide SNP dataset for 170 individuals sampled from six natural populations. Population structure and genetic differentiation were evaluated using Bayesian clustering, analysis of molecular variance (AMOVA), pairwise FST estimates, and network-based visualization. Analyses revealed strong genetic structuring among populations and …

Aquatic Interrelations In Malika Mokeddem’S Novel N’Zid (2001), Laura C. Klein

Green Humanities: A Journal of Ecological Thought in Literature, Philosophy & the Arts

This article offers an ecological analysis of Malika Mokeddem's novel N'Zid (2001), moving beyond postcolonial and anthropocentric interpretations. It centers on the protagonist Nora's individuation, arguing this process is intrinsically linked to her evolving relationship with the aquatic environment from which she emerges. The article aims to situate N'Zid within an ecological perspective, particularly relevant in the Anthropocene, an era compelling a reassessment of humanity's place. Echoing Bruno Latour, addressing inter-relationality is essential as the stable physical framework of the Moderns becomes unstable. This view necessitates rethinking environmental issues and encourages a scientific interpretation of the novel, drawing on neurosciences, …

Listening To Life In A Noisy World: The Pitfalls And Promise Of Urban Acoustic Ecology, Leah O'Barr

Undergraduate Honors Theses

This thesis examines the application of soundscape ecology principles to urban settings. Soundscape ecology is the study of the entire sonic makeup of a community, composed of biophony (biological sound), geophony (environmental sound), and anthrophony (human-generated sound). By examining the changes in and qualities of the soundscape, researchers can gain information about the biological makeup and ecological quality of an area, and the temporal and spatial distribution of resident species. Recent technological advances in recording equipment and machine learning methods are making soundscape ecology an increasingly relevant and practical tool.

Applying soundscape ecology methods to urban ecosystems introduces unique challenges, …

A Population Study Of The Freshwater Turtles Of The Recently Expanded Lake Hydaway In Campbell County, Virginia, Joshua Sorenson

Senior Honors Theses

Freshwater turtles are an important part of the ecological systems in central Virginia. At the recently expanded Lake Hydaway, there are several turtle species for which their population characteristics were unknown, especially the prolific Eastern Painted Turtle (Chrysemys picta picta) and Red-bellied Cooter (Pseudemys rubriventris). For five weeks, the lake was surveyed for turtles using hoop nets, and the turtles were marked and measured. Population characteristics such as carapace length and sex ratio for the Eastern Painted Turtle and Red-bellied Cooter were calculated, as well as population estimates for those two species. The Red-eared Slider ( …

Climate And Gypsum Parent Material Shape Biocrust Communities And Moss Ecology In The Chihuahuan And Mojave Deserts, Katelyn Gobbie, Nicole Pietrasiak, Brian M. Jusko, Rebecca E. Drenovsky

2025 Faculty Bibliography

Biological soil crust communities (biocrusts) establishing on gypsum soils have been well-documented for their prolific appearance and rich diversity of lichens and bryophytes. However, studies characterizing gypsum biocrusts have occurred primarily outside of the U.S., most of which lack comparisons to other soil types. We conducted intensive field surveys to evaluate the ground cover and frequency of biocrust functional groups and moss species on gypsum and non-gypsum soils in the U.S. regions with the most extensive gypsum outcrops, the northern Chihuahuan and eastern Mojave Deserts. Study sites were stratified by geomorphology and paired, so that every gypsum site was matched …

Long-Term Ichthyoplankton Monitoring Of The Moon River (Savannah, Ga) With A Focus On Climate Change, Bradley Cayson

College of Graduate Studies: Theses & Dissertations

The presence of healthy fish populations is a cornerstone of many important ecological mechanisms. These populations are supported by the recruitment of ichthyoplankton, or the egg and larval stages of fishes, as the primary determinant of population growth. Increases in average global water temperatures can alter the composition of fish communities and thus the offspring found in planktonic stages. I compared a large data set of ichthyoplankton surveys completed from 2009-2011 to a replicated six-month sampling period from May – November of 2024. Collection was conducted weekly to biweekly during night flood tides using a fixed suspension ichthyoplankton net (1mm …

Dictyostelids: The Second Major Group Of Slime Molds, P. Liu, Z.J. Zhang, J.H. Ge, Y. Zou, Z. Li, S. Li, Y. Li, S.L. Stephenson

Biological Sciences Faculty Publications and Presentations

The dictyostelids (also called cellular slime molds or social amoebae) are among the more abundant and widespread groups of microorganisms in terrestrial ecosystems. Despite this fact, they are totally unknown to most people, who sometimes confuse the dictyostelids with myxomycetes (or plasmodial slime molds). The first dictyostelid (Dictyostelium mucoroides) was described by the German Oskar Brefeld in 1869. More than 180 species are now known, and these organisms have been recorded from the high arctic to the subantarctic. The primary microhabitat for dictyostelids is the soil/humus layer on a forest floor, but they also occur in a number of other …

Stable Isotope Analyses Of Eye Lenses And Stomach-Content Analysis Reveal Ontogenetic Variation In Arctic Whitefish Trophic Dynamics, Jonah A. Bacon

Fisheries

Determining the ontogenetic trophic ecology of sympatric, morphologically similar fishes is critical for increasing our understanding of life history. We combined bulk and amino acid compound-specific stable isotope analysis of eye lenses with stomach-content analysis to examine ontogenetic trophic dynamics of four amphidromous whitefishes (Arctic Cisco Coregonus autumnalis, Least Cisco C. sardinella, Broad Whitefish C. nasus, Humpback Whitefish C. pidschian) from the central Beaufort Sea, Alaska. Compound-specific stable nitrogen isotope results showed slight increases in trophic position across ontogeny for each species and indicated the feasibility of this method for comparing the trophic ontogenetic development of closely related, mobile predator …

Unraveling The Behavioral Ecology Of The Western Diamond-Backed Rattlesnake (Crotalus Atrox) Through The Lenses Of Personality, Predator-Prey Interactions, And Crypsis, Oceane Da Cunha

Open Access Theses & Dissertations

To thrive in an environment, individuals need to be able to forage efficiently and acquire mates. These resources are limited, and their acquisition depends upon the energy and time an individual chooses to allocate to each activity and the environmental conditions, leading to behavioral trade-offs. Different species, or even different individuals within the same population, respond to these trade-offs by employing contrasting strategies, leading to differential life-history outcomes. The overarching goal of this dissertation is to gain a better understanding of the trade-offs cryptic ambush mesopredators are facing using the western diamond-backed rattlesnake (Crotalus atrox) as a model species. Each …

The Ecology And Genetic Diversity Of Buckleya Distichophylla (Santalaceae), Montana Hill

Masters Theses, 2020-current

Piratebush (Buckleya distichophylla) is a native, rare, shrub found along the Blue Ridge mountains in North Carolina, Virginia, and Tennessee. Research on its ecology and genetic diversity is limited due to its rarity; only one population on Poor Mountain has been studied extensively in the past. To determine if there are ecological differences between populations of B. distichophylla, research on sex distribution, floral visitors, individual length, leaf area, and amount of light that reached each specimen were conducted and then compared between a population located on Dragon’s Tooth Trail and a population on Poor Mountain, both located …

The Virginia Academy Of Science: A Scholarly Forum Over Decades For Students Of A Plant Ecologist, Stewart Ware

Virginia Journal of Science

As a newcomer to Virginia in 1968, I learned that annual meetings of the Virginia Academy of Science (VAS) were regarded as an excellent place for students to have their first experience giving a talk about their research to fellow scientists, and a place for faculty to get to know other Virginia scientists in their fields. Over the next four decades William and Mary students (undergraduate and graduate) and I were presenters or co-authors of 42 talks or posters at VAS annual meetings, 29 of them based on studies of plant ecology across Virginia. Two were talks by colleagues with …

A Biogeographical Appraisal Of The Threatened South East Africa Montane Archipelago Ecoregion, Julian Bayliss, Gabriela B Bittencourt-Silva, William R Branch, Carl Bruessow, Steve Collins, T Colin E Congdon, Werner Conradie, Michael Curran, Savel R Daniels, Iain Darbyshire, Harith Farooq, Lincoln Fishpool, Geoffrey Grantham, Zacharia Magombo, Hermenegildo Matimele, Ara Monadjem, Jose Monteiro, Jo Osborne, Justin Saunders, Paul Smith, Claire N Spottiswoode, Peter J Taylor, Jonathan Timberlake, Krystal A Tolley, Érica Tovela, Philip J Platts

Faculty, Staff and Student Publications

Recent biological surveys of ancient inselbergs in southern Malawi and northern Mozambique have led to the discovery and description of many species new to science, and overlapping centres of endemism across multiple taxa. Combining these endemic taxa with data on geology and climate, we propose the 'South East Africa Montane Archipelago' (SEAMA) as a distinct ecoregion of global biological importance. The ecoregion encompasses 30 granitic inselbergs reaching > 1000 m above sea level, hosting the largest (Mt Mabu) and smallest (Mt Lico) mid-elevation rainforests in southern Africa, as well as biologically unique montane grasslands. Endemic taxa include 127 plants, 45 vertebrates …

Matrilineality, Water Knowledge And Networks, And The Position Of Women In Rural Tanzania, Ruth Aernout, Sara Dewachter, Nathalie Holvoet

Journal of International Women's Studies

This article reports on a study of the effect of matrilineality on a community’s social fabric in the Morogoro region of Tanzania. We used water information-sharing networks as a proxy for social interaction, with water accessibility, functionality, and quality being highly problematic in the area under study. This is a situation that particularly affects women, who are generally responsible for household water provision yet are excluded from water management institutions. Drawing on network and survey data and focus group discussions, the differences in inter-gender interaction, inclusiveness, and women’s status were explored by comparing a matrilineal and mixed patri-matrilineal community. We …

A Comparative Study Of Biocrusts On Gypsum And Non-Gypsum Soils In The Northern Chihuahuan And Eastern Mojave Deserts, Usa: Biocrust Mosses Respond To Soil, Environmental, And Climatic Conditions, Katelyn Gobbie

Masters Theses

Biological soil crust communities (biocrusts) growing on gypsum soils have been well- documented for their prolific appearance and rich diversity of lichens and bryophytes. However, studies characterizing gypsum biocrusts have primarily occurred outside of the U.S., most of which lack comparisons to other soil types. We conducted intensive field surveys to evaluate the cover and frequency of biocrust functional groups and moss species on gypsum and non-gypsum soils in the U.S. regions with the most extensive gypsum outcrops, the northern Chihuahuan and eastern Mojave Deserts. We employed canonical correspondence analysis (CCA) to relate the observed differences in biocrust abundance and …

To Melt, Huanzhe Hu

Masters Theses

This thesis focuses on the need for a reevaluation of the relationship between humans and nature in the face of the current ecological crisis. The author argues that the dominant anthropocentric orientation, which sees nature as a resource to be exploited for human benefit, has led to over extraction and resource abuse, disrupting the balance of ecosystems. Instead, the author suggests adopting an ethical framework based on mutual understanding and appreciation, breaking the "hunter's gaze" and fostering empathy for non-human life forms. This thesis also explores the potential for new forms of communication and engagement with nature, such as through …

“Back To The Jungle”: Investigating Rats, Grass, Scrub Typhus, And Plantations In Malaya, 1924–1974, Jack Greatrex

Research Collection College of Integrative Studies

In this article, I examine epidemiological research into scrub typhus in British Malaya between 1924 and 1974. Interwar research, I show, explained the incidence of the disease through conjunctions of rats, mites, plantations, lalang grass, and “jungle.” In the process, interwar researchers bridged a novel scientific vocabulary centering on disease “reservoirs” with older suspicions of plantations enabling “pests,” as well as with a later, explicitly ecological understanding of infectious disease. In exploring this history I thereby help to re-historicize the emergence of ecological notions of disease reservoirs, whilst also pushing at the limit-points of influential notions of “tropicality.”

The Materiality Of Waka And Ikebana: Locating Ecological Relationships Between Delivery And Arrangement, Bianca Oliveira

All HCAS Student Capstones, Theses, and Dissertations

Rhetorical applications of delivery and arrangement have grown to reflect the global interconnectedness of cultures, bodies, and material objects. Informed by rhetorical and ecological approaches to delivery and arrangement (Edbauer Rice; Lambke;), this project performs a rhetorical and ecological analysis of ikebana (Japanese flower arrangements) and waka (Classical Japanese poetry) by Meishu-Sama and Saigyō Hōshi. Waka and ikebana, as compositional modes, reveal an interpolation of delivery and arrangement that invites both composer and audience to embody nature. As such, this project examines the visual-material and sonic rhetorics of waka and ikebana in order to discover how delivery and arrangement affect …

Abmr: An R Package For Agent-Based Model Analysis Of Large-Scale Movements Across Taxa, Benjamin Gochanour, Javier Fernández-López, Andrea Contina

School of Integrative Biological & Chemical Sciences Faculty Publications

1. Agent-based modelling (ABM) shows promise for animal movement studies. However, a robust, open-source and spatially explicit ABM coding platform is currently lacking.
2. We present abmR, an R package for conducting continental-scale ABM simulations across animal taxa. The package features two movement functions, each of which relies on the Ornstein–Uhlenbeck (OU) process.
3. The theoretical background for abmR is discussed and the main functionalities are illustrated using example populations.
4. Potential future additions to this open-source package may include the ability to specify multiple environmental variables or to model interactions between agents. Additionally, updates may offer opportunities for disease ecology and integration with …

Trophic Ecology And Mercury Concentrations Of Canary Rockfish (Sebastes Pinniger) In The California Current System, Michaela M. Melanson

Master's Theses

Canary rockfish are a profitable fishery resource that has failed and successfully recovered in the 21st century. This study aimed to evaluate their trophic ecology through stomach content and stable isotope analysis and relate these to their mercury concentrations, biological traits, and environmental conditions. Canary rockfish consume mostly krill and teleosts with their geographic location affecting the proportion of prey items, suggesting regional environmental effects: chlorophyll-a, relief, port, and depth impact dietary choices. Mean ??13C values (-17.18 ± 0.54) significantly increased in individuals residing in deeper depths, higher latitudes, higher productivity, and higher temperatures, and in sexually mature individuals. Mean …

Seaweeds Across Ecosystem Boundaries: From Habitat Formation To Harvest Implications, Brian P. Ulaski

Marine Biology

This dissertation broadly investigates the response of wild stock seaweeds to harvesting, and their role as biogenic habitat formers when cast ashore. Seaweeds are important primary producers and foundation species that maintain their functional roles across coastal ecosystem boundaries. Climate-driven loss of seaweed biomass, including that of kelp forests, is exacerbated by other human-related activities that directly impact their persistence, such as overharvesting. Attached rockweeds and kelps are commonly harvested for food, while diverse assemblages of beach-cast seaweed wrack are collected for fertilizer. The importance of wrack habitat in Alaska has not been extensively explored, especially in regions where there …

Niche Overlap In Sympatric Rocio (Teleostei: Cichlidae) Of Guatemala, Cesar Estuardo Fuentes Montejo

College of Science and Health Theses and Dissertations

Rocio is a small genus of Neotropical freshwater fishes that is distributed in Atlantic drainages of northern Middle America. Two species in the genus exhibit sympatry in the Río Dulce basin (in Izabal, Guatemala), where one species is endemic (R. spinosissima), while the other only includes this area as part of a larger geographic range (R. octofasciata). Unfortunately, the ecology of these species has been poorly studied. This study sought to determine the ecological and morphological differences between these two closely related sympatric freshwater fishes. We hypothesized that R. octofasciata would exhibit greater ecological and morphological …

Prevalence Of Mortality Among Covid-19 Patients In Kurdistan Region And Various Parts Of The World And The Role Of Ecological And Environmental Factors In Shaping Sars-Cov-2 Virulence, Muayad A. Mahmud

Polytechnic Journal

Evolutionary theories predict that virulence (host death due to a pathogen) positively associates with the pathogen transmission rates to new susceptible hosts. Severe acute respiratory syndrome coronavirus 2 (SARS- CoV-2), the causative agent of coronavirus disease 2019 (covid-19) pandemic, like other RNA viruses, has quite variable genetic content due to its unique nucleus enzymes thus mutations can continuously occur during viral replications. Phenotype variations among new viral progeny can include individuals with different replication rates, infectivity, stability in the abiotic environment, and transmission rate. Here, the rate of transmission to new susceptible hosts may be affected by the pathogen’s vitality …

Competing Behaviors Of Thermoregulation And Ambush Foraging In The Timber Rattlesnake (Crotalus Horridus Horridus): A Mechanistic Assessment Of Thermal Conduction, Larry K. Kamees

Graduate Theses and Dissertations

The interaction between the biophysical environment and ectotherm morphology elicits behaviors designed to maintain internal body temperature (Tb) within a range that promotes physiological functions. The short-term requirements of mass (energy requirements) and heat balance are subject to tradeoffs imposed by the organisms current physiological (heat and mass budgets) and environmental (biophysical, demographic, social, and predation) constraints and available resources. In temperate forests, extreme temperatures are common in summer even with intermittent sun exposure due to dense canopy cover. In Spring and Fall, temperatures can range from below freezing to 35 ℃ in 24 hrs. An ambush predator like the …

Distribution Patterns Of The Invasive Mussel Arcuatula Senhousia In Mission Bay, San Diego, California: Effects Of Sediment Grain Size And Byssus Thread Production On Predation, Samantha Ahlman

Theses

The ability of bivalves to avoid predation by using defensive behaviors such as burrowing and byssus production may vary depending on the sediment characteristics of a given habitat. The varying sediment characteristics that change with water velocity within estuaries may influence the distribution of bivalves and limit them to areas that optimize their ability to defend against predators. We examined the distribution patterns of the invasive Asian date mussel Arcuatula senhousia relative to the sediment grain size distribution in Mission Bay, an urban estuary located in San Diego, California, USA. Mussels and sediment were collected using an Ekman grab at …

Detection, Occupancy, Abundance, And Mercury Accumulation Of The Alligator Snapping Turtle (Macrochelys Temminckii) In Texas, David Rosenbaum

Electronic Theses and Dissertations

Land use practices and physical alterations of ecosystems result in habitat loss and fragmentation, while chemical alterations, such as pollutant input, reduce habitat quality and health of exposed organisms. Here, I investigated the effects of watershed- and local-scale environmental variables on the occupancy, abundance, and mercury accumulation of a threatened aquatic species (Macrochelys temminckii, i.e., alligator snapping turtle) within the southwestern periphery of its distribution. Hierarchical modeling suggested the distribution of the species is more affected by watershed-scale land-cover than local habitat, and provided a baseline estimate of average species abundance across its range in eastern Texas. Abundance …

Kinorhynch Diversity In The Southern Gulf Of Mexico And A Description Of Dracoderes Chaac Sp. Nov., Stephen C. Landers, Kellan Hoffman, Nuria Sanchez, Martin Sorensen

Gulf and Caribbean Research

Sediment collections from the southern Gulf of Mexico between the Texas—Mexico border and the Yucatán Peninsula have resulted in many new kinorhynch species distribution records and the finding and taxonomic description of a new species, Dracoderes chaac sp. nov. This study focused on the non—echinoderid members of the Phylum Kinorhyncha, many of which are rare or restricted to only a few locations. A total of 136 specimens were identified from 24 sediment stations, distributed among the following species: Antygomonas gwenae, Campyloderes vanhoeffeni, Centroderes readae, Condyloderes flosfimbriatus, Co. rohalorum, Cristaphyes panamensis, Dracoderes chaac sp. nov., …

Research Handling Effects On Stress Hormones, Blood Parameters, And Heart Rate In Juvenile Northern Elephant Seals (Mirounga Angustirostris), Lauren A. Cooley

Master's Theses

Wildlife researchers must balance the need to safely capture and handle their study animals to sample tissues, collect morphological measurements, and attach dataloggers while simultaneously ensuring their results are not confounded by stress artifacts caused by handling. To determine the physiological effects of research activities including chemical immobilization, transport, instrumentation with biologgers, and overnight holding on a model marine mammal species, I collected hormone, blood chemistry, hematology, and heart rate data from 19 juvenile northern elephant seals (Mirounga angustirostris) throughout a translocation experiment. Across my six sampling timepoints, cortisol and aldosterone data revealed a moderate hormonal stress response to handling …

Community Perceptions And Aesthetic Valuation Of Remediation Gardens, Rachel Bechtold

Graduate Theses and Dissertations

Creating successfully remediated landscapes may rely on both natural resources and human perception in landscape design. Urban areas present a dynamic environment wherein communities and nature compete for resources and space. This dissertation study was designed to better understand aesthetic perceptions of native plants capable of land remediation in midwestern communities. Findings from this study show the importance of aesthetic perceptions of stakeholders towards rehabilitated landscapes and the importance of organizing indicators for future design decisions in an interdisciplinary fashion. Recommendations include continued evaluation of aesthetic perceptions for plant species in urban landscapes and modeling a more consistent framework for …

Ocean And Stream Ecology Of Adult Hatchery And Wild Pink Salmon, Julia Mcmahon

Fisheries

In this thesis I investigate potential interactions of hatchery and wild pink salmon (Oncorhynchus gorbuscha) at sea and on the spawning grounds, in the context of the ecological and economic importance of modern Alaskan hatcheries. Although hatchery and wild salmon are known to interact, the nature and outcome of those interactions remain unclear. Here, I identify potential mechanisms of competition and hatchery salmon fitness with two datasets from Prince William Sound, Alaska, home to the largest pink salmon hatchery program in the world. First, I compared fitness-related traits such as body length, return timing, instream lifespan, and egg retention between …