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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 Sep 2023

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 …

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Bison Alter The Northern Yellowstone Ecosystem By Breaking Aspen Saplings, Luke E. Painter, Robert L. Beschta, William J. Ripple Aug 2023

Bison Alter The Northern Yellowstone Ecosystem By Breaking Aspen Saplings, Luke E. Painter, Robert L. Beschta, William J. Ripple

Aspen Bibliography

The American bison (Bison bison) is a species that strongly interacts with its environment, yet the effects of this large herbivore on quaking aspen (Populus tremuloides) have received little study. We documented bison breaking the stems of aspen saplings (young aspen > 2 m tall and ≤ 5 cm in diameter at breast height) and examined the extent of this effect in northern Yellowstone National Park (YNP). Low densities of Rocky Mountain elk (Cervus canadensis) after about 2004 created conditions conducive for new aspen recruitment in YNP's northern ungulate winter range (northern range). We sampled …

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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 Aug 2023

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 …

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Assessing Threats To Plant Populations: Linking Pollinator Differences To Patterns Of Plant Fitness And Population Genetics, Rieka Yu Aug 2023

Assessing Threats To Plant Populations: Linking Pollinator Differences To Patterns Of Plant Fitness And Population Genetics, Rieka Yu

Dissertations

Land use change is a major driver of biodiversity loss and consequently has led to the loss of genetic diversity in many plant populations due to declines in population sizes and an increase in spatial isolation. However, not all plant populations respond similarly to land-use change, suggesting there are additional mechanisms mediating plant population genetic patterns. Here, I examine the role of pollinators as this mediating factor. In Chapter 1 I conducted a meta-analysis to investigate how different types of pollinators drive changes in gene flow for plant populations in disturbed habitats, finding that different types of pollinators mediate different …

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Observations Of The Association By Early-Juvenile Western Rock Lobster Panulirus Cygnus George, 1962 With Seagrass Assemblages (Decapoda: Achelata: Palinuridae), Daphne Oh, Tim J. Langlois, Michael A. Brooker, Hugo Salinas, Jason R. How, Simon De Lestang Aug 2023

Observations Of The Association By Early-Juvenile Western Rock Lobster Panulirus Cygnus George, 1962 With Seagrass Assemblages (Decapoda: Achelata: Palinuridae), Daphne Oh, Tim J. Langlois, Michael A. Brooker, Hugo Salinas, Jason R. How, Simon De Lestang

Fisheries Research Articles

The fishery of the western rock lobster, Panulirus cygnus George, 1962, is Australia’s most valuable wild-caught single-species fishery. Recruitment in some regions of the fishery was observed to be significantly lower than expected after the 2010/2011 West Australian marine heatwave that caused extensive disturbance of dominant coastal habitats. This event generated interest in the study of the factors influencing survival and recruitment of post-larval benthic P. cygnus after settlement. The habitat associations of the highly cryptic post-settlement early-juveniles were previously unknown, with only anecdotal observations of individuals within limestone crevices in nearshore habitats. Our study used early-juveniles derived from …

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Scaled Ecology: A Framework For Evaluating Conservation Of Wildlife Ecological Processes, Johanna A. Hodge Aug 2023

Scaled Ecology: A Framework For Evaluating Conservation Of Wildlife Ecological Processes, Johanna A. Hodge

Biology Theses, Dissertations, and Student Creative Activity

Ecological processes are scaled in time and space, including those associated with wildlife. Understanding the ecological processes of wildlife species and their contributions to ecosystems is crucial for effective conservation. This study focuses on American bison (Bison bison) as a case-study species to explore the holistic scaling of wildlife ecology. A PRISMA-style literature review was conducted to gather and map the scaled ecology of bison. An AIC best-fit analysis was conducted to assess the scaling of total bison ecology considering 7 different models. The results rejected the null model and identified the best-fit model as a combination between fencing and …

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Euscorpius Sulfur Sp. N. (Scorpiones: Euscorpiidae), A New Cave Scorpion From Albania And Northwestern Greece, František Kovařík, Marek Audy, Serban M. Sarbu, Victor Fet Aug 2023

Euscorpius Sulfur Sp. N. (Scorpiones: Euscorpiidae), A New Cave Scorpion From Albania And Northwestern Greece, František Kovařík, Marek Audy, Serban M. Sarbu, Victor Fet

Euscorpius

A new species of cave scorpion, Euscorpius sulfur sp. n. (Scorpiones: Euscorpiidae) from Albania and northwestern Greece is described, fully complemented with color photographs of both live and preserved specimens, as well as their habitats.

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The Devil You Know And The Devil You Don’T: Current Status And Challenges Of Bovine Tuberculosis Eradication In The United States, Daniel J. O'Brien, Tyler C. Thacker, Liliana C.M. Salvador, Anthony G. Duffiney, Suelee Robbe‑Austerman, Mark S. Camacho, Jason E. Lombard, Mitchell V. Palmer Aug 2023

The Devil You Know And The Devil You Don’T: Current Status And Challenges Of Bovine Tuberculosis Eradication In The United States, Daniel J. O'Brien, Tyler C. Thacker, Liliana C.M. Salvador, Anthony G. Duffiney, Suelee Robbe‑Austerman, Mark S. Camacho, Jason E. Lombard, Mitchell V. Palmer

United States Department of Agriculture Wildlife Services: Staff Publications

Having entered into its second century, the eradication program for bovine tuberculosis (bTB, caused by Mycobacterium bovis) in the United States of America occupies a position both enviable and daunting. Excepting four counties in Michigan comprising only 6109 km2 (0.06% of US land area) classified as Modified Accredited, as of April 2022 the entire country was considered Accredited Free of bTB by the US Department of Agriculture for cattle and bison. On the surface, the now well-described circumstances of endemic bTB in Michigan, where white-tailed deer (Odocoileus virginianus) serve as a free-ranging wildlife maintenance host, may appear to be …

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Parasites Versus Predation: The Role Of Chronic And Acute Parasite Exposure In Infection Risk And Anti-Predator Behavior, Delaney Farrell Aug 2023

Parasites Versus Predation: The Role Of Chronic And Acute Parasite Exposure In Infection Risk And Anti-Predator Behavior, Delaney Farrell

All HCAS Student Capstones, Theses, and Dissertations

Parasites with complex, multi-host lifecycles often engage in host behavior manipulation to increase transmission between successive hosts. In intermediate fish hosts, previous research has measured increased frequency of conspicuous behaviors, decreased swimming performance, and reduced antipredator behavior, which would collectively increase the fish’s risk of predation. In ecosystems where this type of parasite increased trophic transmission (PITT) occurs, parasites can play a substantial role in food webs. In this study, I investigate how chronic versus acute exposure to the trematode Euhaplorchis sp. A. affects the antipredator behavior of the Gulf killifish Fundulus grandis. Using a fully crossed design, I …

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A Four-Pronged Approach To Addressing A Wild Pig Invasion In A Bottomland And Upland Forested Landscape, Tyler Scott Evans Aug 2023

A Four-Pronged Approach To Addressing A Wild Pig Invasion In A Bottomland And Upland Forested Landscape, Tyler Scott Evans

Theses and Dissertations

Among exotic species that are capable of invading, establishing, and reaching pest status, few pose the range of impacts to biotic (e.g., competition with native species, predation, herbivory, introduction of other exotics) and abiotic (e.g., soil, hydrology) ecosystem components that can be attributed to the wild pig (Sus scrofa). Despite the presence of wild pigs throughout the southeastern United States for centuries, new invasions continue to occur in previously uninhabited and often under-investigated landscapes, including bottomland and upland forests. The recent invasion of the Sam D. Hamilton Noxubee National Wildlife Refuge (hereafter, NNWR) in east-central Mississippi represents an …

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Catalog Of The World Species Of Trichodesma Leconte, 1861 (Coleoptera: Ptinidae) And Associated Genera, Kyle E. Schnepp Aug 2023

Catalog Of The World Species Of Trichodesma Leconte, 1861 (Coleoptera: Ptinidae) And Associated Genera, Kyle E. Schnepp

Insecta Mundi

A catalog of the species of Trichodesma LeConte (Coleoptera: Ptinidae) for the world is provided, including synonyms and misspellings. Six additional genera, Anobiopsis Fall, Belemia Español, Nanodesma Zahradník, Nicobium LeConte, Trichobiopsis White, and Trichodesmina Español, are also cataloged for com­pleteness. The species name, author, year, and page number of description are given for each species, as well as references for combinations by different authors. The type depository is given when known, and followed by a “?” when unknown but suspected, and a general distribution is given by region of the world followed by country. Authorship of the genus Trichodesma in …

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Behavioral Response To Conspecific Sounds In Loricariid Catfishes (Pterygoplichtys Pardalis And Otocinclus Vittatus), Hephzibah Obafunmiso Aug 2023

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 …

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A Phylogenetic Analysis Of The Leuctra Ferruginea (Walker 1852) Species Group (Plecoptera: Leuctridae), Madison Layer Aug 2023

A Phylogenetic Analysis Of The Leuctra Ferruginea (Walker 1852) Species Group (Plecoptera: Leuctridae), Madison Layer

Masters Theses & Specialist Projects

Leuctra Stephens, 1836 is a genus of Plecoptera (Leuctridae) distributed widely across the Northern Hemisphere, with approximately 210 species reported from eastern North America, Europe, northern Africa, and sporadically across Asia. Eastern North America harbors a small proportion of the global Leuctra fauna (ca. 15% = 31 species), most of which occur in the ancient Appalachian Mountains and unglaciated landscapes in the southeastern USA. Nearctic Leuctra species, except for L. moha and L. crossi, have been divided into five species groups based on external male morphological characteristics. Current phylogenies of Nearctic Leuctra are partial and preliminary, and no comprehensive …

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Assessing The Effect Of Reservoirs On Gene Flow In The Southern Two-Lined Salamander (Eurycea Cirrigera), Anna Favalon Aug 2023

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 …

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Mammalian & Avian Community Response To African Elephant (Loxodonta Africana) Habitat Modification In Southeastern Kenya, Dakota Vaccaro Aug 2023

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) …

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The Effect Of Symbioses Between Mold Mites (Acaridae: Tyrophagus Putrescentiae) And Aspergillus Flavus On Their Respective Populations In Stored Maize., Paige Pionke Cummins Aug 2023

The Effect Of Symbioses Between Mold Mites (Acaridae: Tyrophagus Putrescentiae) And Aspergillus Flavus On Their Respective Populations In Stored Maize., Paige Pionke Cummins

Graduate Theses and Dissertations

Zea mays is the most commonly grown grain in the world and is used for animal feed, human consumption, and the creation of other products such as ethanol and bioplastics. Contamination of stored maize with stored grain invaders can lead to loss of revenue, reduced food availability, and potential health complications. Two such storage invaders; the mold mite Tyrophagus putrescentiae and the fungus Aspergillus flavus can work as symbionts within the grain storage system. To determine resulting population growth from this symbiosis, maize was inoculated with three treatments: A. flavus with no mites, T. putrescentiae with no fungus, and both …

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Tropical Understory And Canopy Twig Ants (Pseudomyrmex): Natural History, Sensory Homing, And Neuroecology., Daniella Prince Aug 2023

Tropical Understory And Canopy Twig Ants (Pseudomyrmex): Natural History, Sensory Homing, And Neuroecology., Daniella Prince

Electronic Theses and Dissertations

In this dissertation, I examined the behavior of foraging twig ants, explored the sensory profile of their homing behavior, and investigated the role of habitat use in shaping the sensory neurobiology of species within the genus Pseudomyrmex (Hymenoptera: Formicidae). In chapter one, I reviewed the ecology of Pseudomyrmex, and introduced the focal species, P. boopis, a neotropical understory-dwelling twig ant. In chapter two, I described the natural history of P. boopis on Barro Colorado Island, Panama—specifically, their nesting habits, activity rhythm, and foraging behavior on understory surfaces. Pseudomyrmex boopis colonies were diurnal and nested in dead twigs in …

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Resolving The Paradox Of Polyploidy: Underexplored Facets Of Polyploid Plants, Benjamin P. Gerstner Aug 2023

Resolving The Paradox Of Polyploidy: Underexplored Facets Of Polyploid Plants, Benjamin P. Gerstner

Biology ETDs

Polyploidy, or whole genome duplication, is a common phenomenon in plants, but the establishment and persistence of mixed-ploidy populations remains a paradox. This dissertation explores factors that contribute to the persistence and establishment of mixed-ploidy populations in nature. The first chapter investigates the role of unreduced gametes in neopolyploid establishment and finds that variability in their formation rate can have a significant impact on polyploid establishment and persistence. The second chapter searches for evidence of soil microbes exhibiting ploidy-specificity, a pre-condition for microbe-mediated niche differentiation, a possible stabilizing mechanism contributing to ploidy coexistence. Finally, the third chapter tests for microbe-mediated …

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Investigation Of Orthohantavirus Genetics In Rodent Reservoirs And Clinical Samples, Samuel Melvin Goodfellow Aug 2023

Investigation Of Orthohantavirus Genetics In Rodent Reservoirs And Clinical Samples, Samuel Melvin Goodfellow

Biomedical Sciences ETDs

Orthohantaviruses are negative-sense, single stranded RNA viruses with trisegmented genomes that can cause severe disease in humans and are carried by several host reservoirs throughout the world. In the United States, Sin Nombre orthohantavirus (SNV) is the primary cause of hantavirus cardiopulmonary syndrome (HCPS) with a fatality rate of ~36% and the highest cases occuring in the southwest region. The primary SNV host reservoir is thought to be the western deer mouse, Peromyscus maniculatus, however it has been shown that other rodents can carry different orthohantaviruses. We designed a pan-orthohantavirus detection tool to survey several small mammal populations throughout New …

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Comparison Of Vegetative Community And Soil Organic Matter Depth Among Reference Sites And Two Restored Wetlands In The Coastal Plain Of South Carolina, Jessica Clark Aug 2023

Comparison Of Vegetative Community And Soil Organic Matter Depth Among Reference Sites And Two Restored Wetlands In The Coastal Plain Of South Carolina, Jessica Clark

All Theses

Wetland loss and degradation from agriculture, urbanization, forestry, and mining is a global issue. South Carolina alone has lost over 27% of its wetlands. This historical wetland loss and climatic changes and impacts make restoring wetlands critical for the state. In restoration, understanding the difference in restored and reference wetland’s vegetation and soil organic matter depth can be crucial in assessing the recovery rate and determining environmental functions and services. The main objectives for our research were to determine differences in soil organic matter depth and vegetative community between the restored Brosnan Forest wetlands, the headwater flats and headwater slopes, …

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New Species Of Dryolestoid From The Late Cretaceous Allen Formation And Implications For South American Faunal Diversity., Brigid Erin Connelly Aug 2023

New Species Of Dryolestoid From The Late Cretaceous Allen Formation And Implications For South American Faunal Diversity., Brigid Erin Connelly

Electronic Theses and Dissertations

Dryolestoids are extinct cladotherians mammals from the Jurassic and Cretaceous periods. I describe a collection of dryolestoid specimens from the Late Cretaceous localities of Cerro Tortuga (Allen Formation), Anfiteatro 1, and Shining (both La Colonia Formation) from Patagonia, Argentina. Using comparative morphology, I identify a new species of meridiolestidan dryolestoid based on eleven specimens across both formations. The new species’ recovery from La Colonia Formation represents the first dryolestoid connection between the two approximately contemporaneous formations. The species’ morphology may represent an ecological shift within Meridiolestida from insectivory to herbivory, showing a transition in characters between the plesiomorphic sharp-toothed meridiolestidans …

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Western Pearlshell (Margaritifera Falcata) Extirpation In The Smith River, Montana, With A Possible Link To Warming Water Temperatures, David M. Stagliano Aug 2023

Western Pearlshell (Margaritifera Falcata) Extirpation In The Smith River, Montana, With A Possible Link To Warming Water Temperatures, David M. Stagliano

Western North American Naturalist

Western pearlshell (Margaritifera falcata) populations are in decline across the species’ range in western North America. In 2008, Montana categorized the western pearlshell as an imperiled species of concern (S2) based on reduced detections at historically occupied sites and few viable populations. Between 2004 and 2014, we surveyed 24 Smith River reaches (61 total sites in the watershed) for the presence of western pearlshell populations. Despite historical and anecdotal descriptions of abundant western pearlshell in the Smith River, intensive structured surveys between 2004 and 2007 documented only 4 sections with low-density, nonviable western pearlshell populations (<10 individuals, large size classes [average total length = 70 mm], with no signs of recruitment). In 2014, we revisited these occupied sites to repeat surveys (expending significantly more search time) and observed no live individuals. This was surprising given that, although those populations would certainly die out without recruitment, older individuals can oftentimes persist for decades. Therefore, we consider the western pearlshell mussel extirpated from the Smith River watershed. We reviewed long-term USGS gage discharge and temperature data near the western pearlshell populations to evaluate the potential causal factors for, and timing of, the extirpation. From 3 July to 3 August 2007, water temperatures were at or above the thermal stress levels of the western pearlshell (>25 °C, …

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Influence Of Abiotic Drivers And Plant Community Interactions On Bald Cypress (Taxodium Distichum) Seedlings: Implications For Restoration, Victoria Ellis Aug 2023

Influence Of Abiotic Drivers And Plant Community Interactions On Bald Cypress (Taxodium Distichum) Seedlings: Implications For Restoration, Victoria Ellis

Biological Sciences Theses & Dissertations

Forested freshwater wetlands are valuable ecosystems that provide habitat for numerous species, sequester carbon, and act as sinks for excess water and nutrients. Historically, these ecosystems have been heavily degraded by anthropogenic activities leading to loss of ecosystem services and a desire to restore freshwater forested wetland habitat. Thus, science-backed approaches for the restoration of freshwater forested wetlands are necessary to ensure restoration goals are met. This body of research employed the Stress Gradient Hypothesis to test whether a multi-species planting approach using Juncus effusus (L.) (soft rush) could facilitate the survival of Taxodium distichum (L.) Rich. (bald cypress) seedlings …

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Tidal Flooding In The Mid-Atlantic Region Of The Us: Water Quality Effects In The Lower Chesapeake Bay, Alfonso Macias Tapia Aug 2023

Tidal Flooding In The Mid-Atlantic Region Of The Us: Water Quality Effects In The Lower Chesapeake Bay, Alfonso Macias Tapia

OES Theses and Dissertations

Many coastal areas around the globe suffer from nutrient pollution and its environmental, social, and economic consequences. Nutrient inputs can come from point (e.g., the end of a pipe) and nonpoint sources, from which the former are better constrained as sampling need only be conducted at a discharge point. Given the temporal and spatially extensive nature of tidal flooding events, they can represent another type of nonpoint source of nutrients to adjacent water bodies heretofore, unexamined and quantified. Most studies examining impacts of tidal flooding have focused on threats to resources on land, such as urban infrastructure and human health …

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Informing Management Strategy For The Relict Leopard Frog (Rana Onca): Insights Into Breeding Biology And An Attempt To Improve Augmentation Success Through Pre-Exposure And Clearance Of An Emerging Amphibian Pathogen, Rebeca Rivera Aug 2023

Informing Management Strategy For The Relict Leopard Frog (Rana Onca): Insights Into Breeding Biology And An Attempt To Improve Augmentation Success Through Pre-Exposure And Clearance Of An Emerging Amphibian Pathogen, Rebeca Rivera

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Relict Leopard Frog, Rana onca, is a species of conservation concern that suffered a decline sometime during the 20th century. Even after two decades of intensive management, the species currently only occupies 20 spring sites in southern Nevada and northwestern Arizona. The causes for the historical decline are mostly speculative, but relate to habitat loss, introduced predators, and emergent disease. Since 2001, R. onca has been under an intensive conservationprogram managed by a multiagency conservation team. There are several objectives specified in the program including the need to investigate the biology of the species and incorporate findings into …

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Emergence, Evolution, And Outcomes Of Community-Based Conservation Behaviors In Coastal Systems, Matthew C. Clark Aug 2023

Emergence, Evolution, And Outcomes Of Community-Based Conservation Behaviors In Coastal Systems, Matthew C. Clark

Boise State University Theses and Dissertations

This body of work leverages a variety of quantitative and theoretical approaches to advance our understanding of why individuals adopt community-based conservation behaviors, the impacts those decisions have on natural resources and human wellbeing, and how these insights can be used for practical conservation planning. The first chapter makes a theoretical contribution by fitting data produced from a stylized, agent-based simulation of conservation adoption over time with a set of probabilistic differential equations derived from the theory of diffusion of innovations and cultural evolutionary theory broadly. We use these methods to demonstrate that such a statistical approach can provide accurate …

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Co-Flowering Community Effects On The Relative Contribution Of Pollen Quantity And Quality Limitation To The Reproductive Success Of Four Clarkia Species, Emma Moore Aug 2023

Co-Flowering Community Effects On The Relative Contribution Of Pollen Quantity And Quality Limitation To The Reproductive Success Of Four Clarkia Species, Emma Moore

Electronic Theses and Dissertations

More than 60% of plant populations experience low pollen availability which limits seed production (pollen limitation). Pollen limitation occurs due to low quantity or quality of pollen delivered to stigmas. Despite its ubiquity in nature, to date we still have limited understanding of the drivers of pollen limitation in plant communities. Plants typically occur in diverse communities where pollinator sharing is common and can influence quality and quantity aspects of pollen limitation. Co-flowering species can attract larger numbers of pollinators or they can compete for pollinators affecting pollen loads on stigmas. Pollinator competition may also lead to higher rates of …

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The Old Family Clock: Exploring High Variation Of Chronotype In The Common House Spider, Parasteatoda Tepidariorum, Caitlin Jones Aug 2023

The Old Family Clock: Exploring High Variation Of Chronotype In The Common House Spider, Parasteatoda Tepidariorum, Caitlin Jones

Electronic Theses and Dissertations

Circadian rhythms are often tightly confined around a mean of 24 hours with little variation in traditional model organisms in the absence of environmental time cues. Some spider species fall well outside this normal range with mean periods of 18 hours and variation around these means of 6 hours or more. This extreme variation in circadian rhythm is not well-understood and is the focus of the current study. Using Parasteatoda tepidariorum as a model organism, we investigated whether variation in eight circadian parameters could be explained by genetic variability, environmental conditions, or an endogenous feature of the circadian system of …

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Impacts Of Urbanization On Pollination Success For Common Milkweed (Asclepias Syriaca), David Rockow Aug 2023

Impacts Of Urbanization On Pollination Success For Common Milkweed (Asclepias Syriaca), David Rockow

Electronic Theses and Dissertations

Urbanization is among the greatest threats to biodiversity on the planet, and is projected to increase in magnitude in coming years. This growing threat makes it important to better understand how urbanization may impact vital ecosystem services, such as pollination. Studies on the impact of urbanization on pollination vary wildly in their findings. This study analyzed multiple aspects of pollination success in common milkweed populations varying in urbanization level, including insect community composition, pollen removal/deposition, and fruit/seed production. By analyzing multiple pollination aspects we can determine the overall mechanism in which urbanization instills on the entire pollination process. Overall, urbanization …

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An Early Pliocene Fish Assemblage From The Southern Appalachians: Ichthyofauna Of The Gray Fossil Site, Shay Maden Aug 2023

An Early Pliocene Fish Assemblage From The Southern Appalachians: Ichthyofauna Of The Gray Fossil Site, Shay Maden

Electronic Theses and Dissertations

The Gray Fossil Site (GFS) preserves an early Pliocene sinkhole pond that accumulated a rich flora and vertebrate fauna. Fossils of fish are incredibly common at GFS, representing thousands of specimens recovered to date. Comparison with extant species reveals a depauperate freshwater fish fauna consisting of only two species: Lepomis sp. and Micropterus sp. The absence of fishes that are ubiquitous in modern streams suggests no perennial surface hydrologic connection between the Gray Fossil Site and the nearby Holston River. Limited opportunities for dispersal into the pond and deleterious conditions such as eutrophy and high competition may have resulted in …

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