Biology Commons^™

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

Graduate Theses and Dissertations

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

Seagrass Epibiont Biodiversity In The Northern Gulf Of Mexico, Kathryn Wyssmann

LSU New Orleans Theses and Dissertations

Epibionts on seagrass leaves contribute substantially to productivity and trophic interactions in seagrass ecosystems. Differences in epibiont assemblages and factors that contribute to epibiont diversity have been little studied on the seagrass Halodule wrightii in the northern Gulf of Mexico (nGoM). We used a metabarcoding approach to describe epibiont assemblages on H. wrightii leaves in four bays across the nGoM and to test whether epibiont assemblages differed spatially at local levels (within bays) or regional levels (from west to east). Furthermore, we tested if epibiont diversity was related to environmental conditions and/or seagrass productivity. Epibiont assemblages differed significantly between bays …

Impacts Of Disturbance And Nutrient Addition On Coastal Dune Arthropod Communities, Kayla Beitzel

Honors Theses

Coastal dune ecosystems are globally distributed ecosystems that occur from the tropics to the poles and serve as the first line of defense during storms. They are critical habitats for a variety of organisms and also play a critical role in stabilizing coastal habitats. These systems face increased pressure via urban development, recreational expansion, and sea-level rise (Newman et al. 2023; Webster et al. 2005). Insects are vital consumers in coastal ecosystems and act as regulators of plant growth. Low-diversity ecosystems, like coastal dune systems, often contain a higher abundance of low-diverse insect consumers (Ripple et al. 2021), which can …

Unlocking The Mysteries Of Opportunism: Neuroendocrine Insights From An Aseasonal Breeder (Taeniopygia Guttata), Jessica A. Moodie

Graduate Theses and Dissertations (2019 - present)

The regulation of reproductive physiology in animals is mediated by the Hypothalamus-Pituitary-Gonad (HPG) axis. In seasonal breeders, a conserved reciprocal switching of deiodinase enzymes alters thyroid hormone signaling, which controls HPG activity. This study tested the hypothesis that neural regulation of the HPG axis as described in seasonal systems is conserved and repurposed to respond to other cues in aseasonal species. Using water deprivation and nest restriction in the opportunistic Zebra Finch, we were able to create a breeding group and non-breeding group, confirmed by egg laying and changes in ovarian anatomy. Breeding females had clear follicular hierarchy, increased ovary …

Lizard Communities In A Shifting Landscape: The Current State Of Insectivorous Lizard Communities In The Jornada Basin Between Grassland, Mesquite Dune, And Creosote Bush Habitats In A Semi-Arid Landscape Undergoing Shrubification, Julie Marie Schlichte

Open Access Theses & Dissertations

Lizard communities in arid lands can act as model systems of how diversity and abundance are impacted in the face of ongoing climate variability and change, as they are sensitive to shifts in precipitation, temperature, and changing vegetation structure. The main research question we hope to answer is how the community composition of lizards varies between dominant vegetation types (Mesquite dunes, grasslands, and Creosote Bush flats). Nine sites (3 of each dominant vegetation type) with 16 pitfall traps each (n = 144) were surveyed from June 2016 -- June 2017. 12 lizard species were captured, consisting of 923 total captures …

Effects Of Landcover On Mesocarnivore Density And Detection Rate Along An Urban To Rural Gradient, Leah E. Mctigue, Brett Degregorio

Biological Sciences Faculty Publications and Presentations

Human development has major implications for wildlife populations. Urban-exploiter species can benefit from human subsidized resources, whereas urban-avoider species can vanish from wildlife communities in highly developed areas. Therefore, understanding how the density of different species varies in response to landcover changes associated with human development can provide important insight into how wildlife communities are likely to change and provide a starting point for predicting the consequences of those changes. Here, we estimated the population density of five common mesocarnivore species (coyote (Canis latrans), bobcat (Lynx rufus), red fox (Vulpes vulpes), raccoon (Procyon …

Breaking Virulent: The Coincidental Evolution Of Virulence Factors In Bacteria., Rhiannon Emmanuelle Cecil

Electronic Theses and Dissertations

Understanding how innocuous organisms can evolve to be pathogenic to humans is of increasing global concern. Further, understanding how existing pathogens may evolved to be more virulent is also vital to our ability to provide healthcare to people afflicted with diseases that promote chronic bacterial infections, such as cystic fibrosis. With the rise of antibiotic resistance in both bacteria and fungi it is paramount that new therapeutics are identified. Understanding what mutations occur that result in increased virulence in microbes can potentially provide new targets for antimicrobial drugs to combat antibiotic resistance. The Coincidental Evolution Hypothesis is a fundamental hypothesis …

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

Graduate Theses and Dissertations

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

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

Graduate Theses and Dissertations

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

Activity Patterns Of Whiptail Lizards (Aspidoscelis) Found In The Northern Chihuahuan Desert, Guillermo Alvarez

Open Access Theses & Dissertations

Traditional lizard pitfall traps were modified to allow organisms to escape, while collecting valuable ecological data. Modified camera traps were capable of detecting the same species as traditional traps in a semi-arid environment, without posing the associated mortality risks. Pitfall-camera traps were used to sample the activity of the Side-blotched Lizard (Uta stansburiana) and the Southwestern Fence Lizard (Sceloporus cowlesi) in an urban wetland during four continuous years. Evaluations on activity pattern and the activity overlap between the two species revealed extensive overlap, with minor but significant seasonal shifts mediating coexistence. Traps were also effective at detecting other reptiles, invertebrates, …

Quantifying The Role Of Water Quality On Nitrogen Cycling In A Trophic Estuary, Kayla Gonzalez-Boy

Symposium of Student Scholars

Jobos Bay Estuary is an intertidal, tropical estuary located in southern Puerto Rico. The estuary covers about 12 km² and has a variety of habitats, such as seagrass beds, mangroves, mud flats, and coral reefs, which play important roles in sediment trapping and water quality maintenance. Seagrasses also serve as nursery and feeding grounds and provide shelter for macrofauna. Currently, the role of seagrasses and water quality on nitrogen (N) cycling in trophic estuaries is not well constrained. Understanding variations in sediment-based effects on N cycling rates and transformations, and how they are associated with water quality, is an …

Individual And Population Age Impact Social Behavior And Network Structure In A Long-Lived Insect, P. A. Cook, R. A. Costello, Vincent A. Formica, E. D. Brodie Iii

Biology Faculty Works

Social behaviors vary among individuals, and social networks vary among groups. Understanding the causes of such variation is important for predicting or altering ecological processes such as infectious disease outbreaks. Here, we ask whether age contributes to variation in social behavior at multiple levels of organization: within individuals over time, among individuals of different ages, among local social environments, and among populations. We used experimental manipulations of captive populations and a longitudinal dataset to test whether social behavior is associated with age across these levels in a long-lived insect, the forked fungus beetle (Bolitotherus cornutus). In cross-sectional analyses, …

Effects Of A Major Hurricane On Dynamics, Structure, And Composition Of Mississippi River Delta Forests, Lance C. Umlang

LSU Doctoral Dissertations

Tropical cyclones recurrently influence coastal forests worldwide. Tree survival (resistance) and post-cyclone recruitment (resilience) can vary with cyclone intensity, producing differences in composition, arboreal structure, and dynamics among affected forests. Studies of tropical cyclone wind effects on coastal forests typically emphasize damage more than post-cyclone responses. We hypothesized that intense cyclones might produce large, stratum-dependent effects that prevent affected forests from returning to pre-storm conditions. We explored direct effects of major Hurricane Katrina and post-hurricane changes in oak-dominated bottomland and cypress/tupelo-dominated swamp forests within the inactive portion of the Mississippi River deltaic plain. Overall mortality was high (14-25%) but concentrated …

Ecological Correlates For Endemic And Threatened Amphibians In The Uluguru Nature Forest Reserve, Tanzania, Joseph M. Christopher, Wilirk Ngalason, John V. Lyakurwa

Tanzania Journal of Science

Information on habitat characteristics for endemic and threatened amphibians along the altitudinal gradient in the Uluguru Nature Forest Reserve (UNFR) is limited. We assessed habitat characteristics associated with the occurrence of endemic and threatened amphibians in the Uluguru Nature Forest Reserve between April and June 2022. Bucket pitfall traps, time-constrained audio-visual surveys, plots and opportunistic searching were used to study amphibians in 6 sites along elevational gradient from 600 m to 2100 m a.s.l. Eighteen amphibian species were recorded, thirteen of them being endemic to the Eastern Arc Mountains, two near-endemic and three widely distributed. Among the species recorded, seven …

Freshwater Macroinvertebrate Communities In Baldwin County, Georgia, Heath Michael Ghioto, Michelle K. Murdock, Nadya S. Gutierrez, Kristine N. White Ph.D.

Georgia Journal of Science

Freshwater ecosystems are critical habitats for maintaining biodiversity, often providing refuge for organisms especially in urban settings. Baldwin County, GA is home to many freshwater lakes that are part of the Oconee River watershed. Despite ongoing water quality monitoring, aquatic macroinvertebrates are under studied in the area. Aquatic macroinvertebrate diversity of one forested and one residential lake in Milledgeville, GA was documented for the first time. Despite low sample size, community composition was significantly different between lakes, with 27 families in Lake Laurel (forested), 44 families in Lake Oliver Hardy (residential), and only 19 families collected from both lakes. Seasonal …

Spatial Structure Of Germination And Seed-Associated Fungi In Tropical Pioneer Seeds, Daniela Varon Garcia

USF Tampa Graduate Theses and Dissertations

Negative density-dependent regulation is the process by which host-specific natural enemies reduce the survival of seeds and seedlings of conspecifics near adult trees, favoring heterospecific recruitment, and ultimately increasing local diversity. Negative density-dependent regulation by fungal pathogens has been consistently reported to promote plant diversity in the tropics, even though they tend to be multi-host and host-specificity is rarely reported. Nevertheless, evidence suggests that host-generalist fungi can have host-specific effects that produce disproportionate negative effects on some plant species but not others, promoting regional diversity. However, such studies have not tested for both host-specificity and distance-dependent effects in fully replicated …

Reimagining Large River Management Using The Resist–Accept–Direct (Rad) Framework In The Upper Mississippi River, Nicole K. Ward, Abigail J. Lynch, Erik A. Beever, Joshua Booker, Kristen L. Bouska, Holly Embke, Jeffrey N. Houser, John F. Kocik, David J. Lawrence, Mary Grace Lemon, Doug Limpinsel, Madeline R. Magee, Bryan M. Maitland, Owen Mckenna, Andrew Meier, John M. Morton, Jeffrey D. Muehlbauer, Robert Newman, Devon C. Oliver, Heidi M. Rantala, Greg G. Sass, Aaron Shultz, Laura M. Thompson, Jennifer L. Wilkening

Biology Faculty Publications

Background Large-river decision-makers are charged with maintaining diverse ecosystem services through unprecedented social-ecological transformations as climate change and other global stressors intensify. The interconnected, dendritic habitats of rivers, which often demarcate jurisdictional boundaries, generate complex management challenges. Here, we explore how the Resist–Accept–Direct (RAD) framework may enhance large-river management by promoting coordinated and deliberate responses to social-ecological trajectories of change. The RAD framework identifies the full decision space of potential management approaches, wherein managers may resist change to maintain historical conditions, accept change toward different conditions, or direct change to a specified future with novel conditions. In the Upper Mississippi …

The Effects Of Landscape And Yard Features On Mammal Diversity In Residential Yards Within Northwest Arkansas, Usa, Emily P. Johansson, Brett A. Degregorio

Biological Sciences Faculty Publications and Presentations

The human footprint is rapidly expanding, and wildlife habitat is continuously being converted to human residential properties. Surviving wildlife that reside in developing areas are displaced to nearby undeveloped areas. However, some animals can co-exist with humans and acquire the necessary resources (food, water, shelter) within the human environment. This ability to coexist may be particularly true when development is low intensity, as in residential suburban yards. Yards are individually managed “greenspaces” that can provide a range of food (e.g., bird feeders, compost, gardens), water (bird baths and garden ponds), and shelter (e.g., brush-piles, outbuildings) resources and are surrounded by …

The Himalayan Uplift And Evolution Of Aquatic Biodiversity Across Asia: Snowtrout (Cyprininae: Schizothorax) As A Test Case, Binod Regmi, Marlis R. Douglas, Karma Wangchuk, Zachery D. Zbinden, David R. Edds, Singye Tshering, Michael E. Douglas

Biological Sciences Faculty Publications and Presentations

Global biodiversity hotspots are often remote, tectonically active areas undergoing climatic fluctuations, such as the Himalaya Mountains and neighboring Qinghai-Tibetan Plateau (QTP). They provide biogeographic templates upon which endemic biodiversity can be mapped to infer diversification scenarios. Yet, this process can be somewhat opaque for the Himalaya, given substantial data gaps separating eastern and western regions. To help clarify, we evaluated phylogeographic and phylogenetic hypotheses for a widespread fish (Snowtrout: Cyprininae; Schizothorax) by sequencing 1,140 base pair of mtDNA cytochrome-b (cytb) from Central Himalaya samples (Nepal: N = 53; Bhutan: N = 19), augmented with 68 GenBank …

Compensating For Effects Of Autotomy On Locomotion In Stink Bugs (Halyomorpha Halys), Lilian C. Jubb

Longwood Senior Thesis Proposal

Autotomy is the voluntary release of an appendage, typically to avoid predation or entrapment. Autonomy of a single leg can have minimal effects on locomotion in arthropods with more than six legs. Hexapods, however, use a double-tripod gait which is completely disrupted with the loss of a single leg, thus locomotor performance should be greatly reduced leading to lower survival. Autotomy is so costly to locomotion that some insects regenerate a lost limb in a subsequent molt leading to reduced investment in other important functions (e.g. reproduction). Autotomy persists in adult hexapods with no opportunity for regeneration, which suggests some …

South Coast Offshore Crustacean Resource Of Western Australia Harvest Strategy, Department Of Primary Industries And Regional Development, Western Australia

Fisheries Management Papers

Harvest strategies for aquatic resources in Western Australia (WA) that are managed by the Department of Primary Industries and Regional Development (DPIRD, the Department) are formal documents that ensures decision-making processes are consistent with the principles of Ecologically Sustainable Development (ESD; Fletcher 2002) and Ecosystem Based Fisheries Management (EBFM; Fletcher et al. 2012). The objectives of ESD are reflected in the objects of the Fish Resources Management Act 1994 (FRMA) and the Aquatic Resources Management Act 2016 (ARMA), which is anticipated replace the FRMA once enacted. At this point, the Fish Resources Management Regulations 1995 (FRMR) is also anticipated to …

Water Quality Of Madari Khal Tributary Of The Halda River, Chattogram, Bangladesh, Md. Shafiqul Islam, M.A. Azadi

Journal of Bioresource Management

Tidal canal Madari-Khal is one of the important tributaries of the river Halda, through which nearby hill stream water, agricultural washings, and effluents (treated or untreated) of Chattogram Asian paper Mill are drained to the Halda River. In this paper water quality and pollution level of Madari Khal are presented. A one-year study was conducted to ascertain the water quality and pollution level by using different physicochemical parameters i.e. Air temperature, Water temperature, Transparency, EC (Electrical Conductivity), TDS (Total Dissolved Solids), pH, DO (Dissolved Oxygen), freeCO₂, Ca⁺⁺ (Calcium), TH (Total Hardness), TA (Total Alkalinity), and Biological Oxygen …

Effects Of Fire On Kangaroo Rats In The San Joaquin Desert Of California, David J. Germano, Lawrence R. Saslaw, Brian L. Cypher, Linda Spiegel

Western North American Naturalist

Fire can alter ecological communities, particularly those that are not fire-adapted, such as desert communities. We examined the effects of fire on rodent communities in the San Joaquin Desert of central California. Of particular interest were the effects on kangaroo rats (Dipodomys spp.) including 2 rare species, the giant kangaroo rat (D. ingens) and the short-nosed kangaroo rat (D. nitratoides brevinasus). Lightning caused multiple fires in arid scrub habitat in western Kern County in 1993. We trapped rodents at 7 sites along paired transects, with one transect in a burned area and one in a …

Past And Ongoing Field-Based Studies Of Myxomycetes, Steven L. Stephenson

Biological Sciences Faculty Publications and Presentations

Evidence from molecular studies indicates that myxomycetes (also called myxogastrids or plasmodial slime molds) have a long evolutionary history, and the oldest known fossil is from the mid-Cretaceous. However, they were not “discovered” until 1654, when a brief description and a woodcut depicting what is almost certainly the common species Lycogala epidendrum was published. First thought to be fungi, myxomycetes were not universally recognized as completely distinct until well into the twentieth century. Biodiversity surveys for the group being carried out over several years are relatively recent, with what is apparently the first example being carried out in the 1930s. …

Determining The Influence Of Abiotic And Biotic Predictors On Ecological Niche Models, Erica Johnson

Dissertations, Theses, and Capstone Projects

Biotic variables, including those reflecting interactions such as competition and parasitism, are generally assumed to have negligible effects on broadscale species distributions and are typically excluded from ecological niche models (ENMs). However, the role such interactions play in shaping species distributions is increasingly recognized, sparking the development of methods for their integration into ENMs.

Among the most common approaches are those that limit the ENM output of the focal species by the distribution of biotic interactors (post-processing) and those that incorporate biotic interactors as predictor variables. These endeavors hold widespread and critical usages, such as predicting the impacts of climate …

Sex In The Noisy City: Changes In Vocal Behavior Patterns And Dopamine Neurochemistry In The Auditory System Of Oyster Toadfish (Opsanus Tau), Kelsey N. Hom

Dissertations, Theses, and Capstone Projects

Intense anthropogenic noise can induce stress, behavioral changes, and even hearing loss in aquatic animals. However, there are few studies that have demonstrated how ecologically relevant noise affects aquatic life, and even fewer studies on the effect of noise on animals that require sound for reproduction. The oyster toadfish (Opsanus tau) is an excellent animal model to examine the effects of anthropogenic noise on behavior and neurochemistry since they use a reproductive call to find mates and live near urban areas like New York City. Despite living alongside the most populous city in the United States, these vocal …

Go Big Or Go Home: Divergence In Morphology And Behavior Between Island And Islet Populations Of The San Cristóbal Lava Lizard (Microlophus Bivittatus), Emilio J. Mancero

Masters Theses

Rapid divergence in body size is a well-documented phenomenon among island species, associated with macroevolutionary processes of diversification and adaptive radiation. The effect of insularity in determining larger body size as an optimal phenotype is primarily attributed to lower predation and greater intraspecific competition on islands. Our study examined interpopulation variation in morphology, social behavior and predator avoidance in Galápagos lava lizards endemic to San Cristóbal island (Microlophus bivittatus), and the nearby islet Isla Lobos. Islet populations have fewer competitors than those on the island, where native and introduced predators are abundant. We simulated interactions with predators and …

Behavioral Response To Conspecific Sounds In Loricariid Catfishes (Pterygoplichtys Pardalis And Otocinclus Vittatus), Hephzibah Obafunmiso

Masters Theses & Specialist Projects

Sound production is a means of communication among many fish species. In fishes, sound is produced through various mechanisms, but in the family Loricariidae, known as armored suckermouth catfishes, sound is produced primarily through pectoral fin spine stridulation. Previous experiments have described the sounds produced and shown the mechanism of sound production in two species of loricariid catfishes, Pterygoplichthys gibbiceps and Otocinclus affinis, but the functional significance of loricariid sounds is still unknown. To address this question, I examined the behavioral responses of Pterygoplichthys pardalis and Otocinclus vittatus to conspecific calls. Individual fish (N=10 for P. pardalis) or groups …

Assessing The Effect Of Reservoirs On Gene Flow In The Southern Two-Lined Salamander (Eurycea Cirrigera), Anna Favalon

Masters Theses & Specialist Projects

Biodiversity is an essential component of natural environmental dynamics. Unfortunately, diversity is threatened by human activities and relies on conservation efforts. An important aspect of biodiversity conservation lies in protecting population connectivity and gene flow. In the mid-1900s, many Kentucky rivers were dammed, creating deep, lentic reservoirs in the valleys once occupied by dynamic, lotic rivers. For species inhabiting the rivers and associated tributaries, the central reservoirs may reduce connectivity among populations and impose a barrier to gene flow. The connectivity of populations on landscapes altered by the creation of reservoirs can be assessed by merging the principles of landscape …

Mammalian & Avian Community Response To African Elephant (Loxodonta Africana) Habitat Modification In Southeastern Kenya, Dakota Vaccaro

Masters Theses & Specialist Projects

African elephants (Loxodonta africana) play a significant role in the modification of their habitat, foremost by decreasing woody vegetation cover and density and in some parts of Africa high elephant densities damage small sanctuaries and preserves. For wildlife that depend on forested patches, this increased modification could lead to displacement and/or decreases in abundance. If suitable habitat is not available elsewhere, elephants and other wildlife may move closer to humans in search of resources, which can result in increased human-wildlife conflict. Evaluating this impact was one of the goals of the Elephants and Sustainable Agriculture in Kenya (ESAK) …