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Full-Text Articles in Biology

Refining The Use Of Stable Isotope Analysis In Detecting Wildlife Laundering, Kevin Guilfoyle Jan 2023

Refining The Use Of Stable Isotope Analysis In Detecting Wildlife Laundering, Kevin Guilfoyle

Electronic Theses and Dissertations, 2020-

The international wildlife trade has caused significant declines in wild populations. Captive breeding can reduce the pressure on wild populations caused by overcollection, but if not properly monitored, wildlife laundering can lead to further population declines. Improving the forensic ability to detect wildlife laundering will assist in monitoring the wildlife trade and enforcing regulations, thereby aiding recovery of wild populations. Stable isotope analysis has grown in importance as a forensic tool, but improvements are needed. Here, stable isotope analysis (δ13C) on eggshells of captive bred and wild sourced island apple snails (Pomacea maculata) distinguished between the two; eggshells of captive …


Dormant Propagules In Demographic Studies: A Recurrent Bias And Potential Solutions, Federico Borghesi Jan 2023

Dormant Propagules In Demographic Studies: A Recurrent Bias And Potential Solutions, Federico Borghesi

Graduate Thesis and Dissertation 2023-2024

In the face of unprecedented anthropogenic change, we increasingly turn to emergent technologies and extensive data sets for solutions that complement much needed systemic changes in our societies. These technological solutions, however, must be approached with care. We must recognize and address biases in the way data has been accumulated. In demographic studies, dormant life stages, such as seed banks, and other cryptic factors have often been neglected. The potential consequences of these omissions have been extensively described in the literature. In the first chapter, I analyze patterns of seed bank omissions in demographic models, finding unjustified omissions are widespread …


Evolutionary History And Adaptation To Salinity In American Alligators, John Konvalina Jan 2023

Evolutionary History And Adaptation To Salinity In American Alligators, John Konvalina

Electronic Theses and Dissertations, 2020-

Stressful environments can commonly be found at the edge of a species range and may be a driver for adaption in suboptimal environments. Furthermore, the edge of a species' range can expand and contract over time, resulting in multiple independent invasions of the same stressful habitat. Elucidating population genetic structure and demographic history can aid in determining the which geologic factors impact range distributions and when climatic changes occurred driving genetic patterns observed in contemporary populations. Moreover, populations at the edge of the species range may adapt to the stressful environments that occur at the range edge and exhibit genetic …


Synergistic Impacts Of Climate Change And Human Induced Stressors On The Apalachicola Bay Food Web, Kira Allen Jan 2022

Synergistic Impacts Of Climate Change And Human Induced Stressors On The Apalachicola Bay Food Web, Kira Allen

Electronic Theses and Dissertations, 2020-

Apalachicola Bay, an estuary located in northwest Florida, is likely to experience an increase in climate change and human-induced stressors, such as sea level rise and changes in freshwater inflow, in the future. A coupled hydrodynamic and food web modeling approach was used to simulate future scenarios of low and high river flow and sea level rise in Apalachicola Bay from 2020 to 2049 and demonstrate the range of temporal and spatial changes in water temperature, salinity, fisheries species populations and the broader food web. Concurrent with model development, a survey of Apalachicola Bay stakeholders was conducted to assess stakeholder …


"Reeling In" Juvenile Sportfish Through Coastal Habitat Restoration: Population, Community, And Trophic Responses In The Indian River Lagoon, Florida, Jennifer Loch Jan 2022

"Reeling In" Juvenile Sportfish Through Coastal Habitat Restoration: Population, Community, And Trophic Responses In The Indian River Lagoon, Florida, Jennifer Loch

Electronic Theses and Dissertations, 2020-

Coastal habitats provide crucial nursery habitat for predatory fishes, but they are in decline worldwide, impacting economically important fisheries. Habitat restoration can simultaneously mitigate the effects of habitat loss and benefit predators (e.g., sportfish), although this relationship is understudied. Here, the response of juvenile sportfish to oyster reef and living shoreline restoration is compared to controls in the Indian River Lagoon, Florida prior to and following restoration for up to three years through examination of community (diversity, assemblage), population (abundance), biometric (size, body condition), ontogenetic, and trophic (gut contents, stable isotopes) dynamics. Stable isotopes were used to quantify dietary history, …


Biogeochemical Effects Of Sea Level Rise-Induced Transitions Within Coastal Wetlands, Havalend Steinmuller May 2019

Biogeochemical Effects Of Sea Level Rise-Induced Transitions Within Coastal Wetlands, Havalend Steinmuller

Electronic Theses and Dissertations

As sea level rise (SLR) affects coastal wetlands, ecosystem responses can include vertical accretion, landward transgression, or submergence. Sea level rise-induced transitions can alter key biogeochemical transformations within wetland soils, impacting the ability of these systems to provide ecosystem services, specifically carbon (C) storage and water quality regulation. Through a series of complementary laboratory and field-based studies, biogeochemical responses to salinity, vegetation shifts, and submergence were investigated. Changes in nutrient dynamics associated with saltwater intrusion were evaluated by artificially adding saline water to different freshwater wetland soil types, indicating that potential exports of critical nutrients (forms of nitrogen, phosphorus, and …


Seascape Genetics And Rehabilitation Efficiency In The Florida Manatee, Madison Hall Jan 2019

Seascape Genetics And Rehabilitation Efficiency In The Florida Manatee, Madison Hall

Electronic Theses and Dissertations

The Florida manatee (Trichechus manatus latirostris) was recently downlisted federally from "endangered" to "threatened" despite acknowledgments of remaining threats to long term population persistence. Challenges to future manatee conservation include, but are not limited to, increases in frequency of harmful algal blooms, intensifying anthropogenic disturbance, and loss of warm-water habitat. The goals of this dissertation were 1) to assess threats to the manatee via a comprehensive, long-term (1973-2016), retrospective analysis of the manatee rescue and rehabilitation partnership (MRRP) and 2) to use seascape genetics analysis to examine whether abiotic, biotic, or anthropogenic seascape variables could significantly describe genetic distance patterns …


An Examination Of Beta Diversity Indices And Their Predictors In Two Large-Scale Systems, Philip Schroeder Jan 2018

An Examination Of Beta Diversity Indices And Their Predictors In Two Large-Scale Systems, Philip Schroeder

Electronic Theses and Dissertations

Biodiversity is what conservation biology was developed to conserve. It is the physical manifestation of life as a concept and, be it for practical or idealistic reasons, all conservationists seek to protect or, in some cases, enhance it. Because of its monolithic importance to the field, much effort has been expended trying to better measure and understand it. Recently, greater attention has been paid to the partition of diversity; the observation that the total diversity of a system (γ) can be broken down into within-site diversity (α) and between-site diversity (β). In particular, it has been noticed that the β …


Evolution And Distribution Of Phenotypic Diversity In The Venom Of Mojave Rattlesnakes (Crotalus Scutulatus), Jason Strickland Jan 2018

Evolution And Distribution Of Phenotypic Diversity In The Venom Of Mojave Rattlesnakes (Crotalus Scutulatus), Jason Strickland

Electronic Theses and Dissertations

Intraspecific phenotype diversity allows for local adaption and the ability for species to respond to changing environmental conditions, enhancing survivability. Phenotypic variation could be stochastic, genetically based, and/or the result of different environmental conditions. Mojave Rattlesnakes, Crotalus scutulatus, are known to have high intraspecific venom variation, but the geographic extent of the variation and factors influencing venom evolution are poorly understood. Three primary venom types have been described in this species based on the presence (Type A) or absence (Type B) of a neurotoxic phospholipase A2 called Mojave toxin and an inverse relationship with the presence of snake venom metalloproteinases …


Reproductive Life History And Signal Evolution In A Multi-Species Assemblage Of Electric Fish, Joseph Waddell Jan 2017

Reproductive Life History And Signal Evolution In A Multi-Species Assemblage Of Electric Fish, Joseph Waddell

Electronic Theses and Dissertations

Animals that co-occur in sympatry with multiple closely-related species use reproductive mate attraction signals not only to assess the quality of a potential conspecific mate (sexual selection), but also to discriminate conspecifics from heterospecifics (species recognition). However, the extent to which sexual selection and species recognition may interact, or even conflict, is poorly known. Neotropical electric fish offer unrivaled opportunities for understanding this problem. They generate simple, stereotyped mate attraction signals that are easy to record and quantify, and that are well-understood from the neurobiological perspective. Additionally, they live in electrically-crowded environments, where multiple congeners live and reproduce in close …


The Role Of The Y-Chromosome In The Evolution Of Autosomally Coded Traits, Ian Kutch Jan 2017

The Role Of The Y-Chromosome In The Evolution Of Autosomally Coded Traits, Ian Kutch

Electronic Theses and Dissertations

Recent work indicates that the Y-chromosome of the fruit fly Drosophila melanogaster can influence gene regulation on the autosomes and X chromosome. This newly discovered function of the Y has the potential to dramatically shape the regulatory evolution of numerous genes that reside throughout the genome; even for genes that code for both male and female traits. Given that the mechanism underlying the Y-linked influence on gene expression in D. melanogaster appears to exist in other independently evolved heterogametic sex chromosomes, the evolutionary implications of Y-linked regulatory variation (YRV) deserves to be explored. These implications include the potential for Y-chromosomes …


Using Landscape Genetics To Assess Population Connectivity In A Habitat Generalist, Tyler Duncan Hether Jan 2010

Using Landscape Genetics To Assess Population Connectivity In A Habitat Generalist, Tyler Duncan Hether

Electronic Theses and Dissertations

Understanding the nature of genetic variation in natural populations is an underlying theme of population genetics. In recent years population genetics has benefited from the incorporation of landscape and environmental data into pre-existing models of isolation by distance (IBD) to elucidate features influencing spatial genetic variation. Many of these landscape genetics studies have focused on populations separated by discrete barriers (e.g., mountain ridges) or species with specific habitat requirements (i.e., habitat specialists). One difficulty in using a landscape genetics approach for taxa with less stringent habitat requirements (i.e., generalists) is the lack of obvious barriers to gene flow and preference …


The Influence Of Sexual Selection On Behavioral And Physiological Mechanisms Underlying Reproductive Success In Male Cape Ground Squirrels (Xerus Inauris), Mary Beth Manjerovic Jan 2010

The Influence Of Sexual Selection On Behavioral And Physiological Mechanisms Underlying Reproductive Success In Male Cape Ground Squirrels (Xerus Inauris), Mary Beth Manjerovic

Electronic Theses and Dissertations

Sexual selection is considered a powerful evolutionary force responsible for the enormous diversity found in reproductive morphology, physiology, and behavior. I addressed questions related to selection in the Cape ground squirrel (Xerus inauris), a species characterized as highly social and promiscuous. These attributes often are responsible for variance in male reproductive success and as such, sexual selection theory predicts increased opportunity for sexual selection. I confirm that the predominant mechanism underlying genital evolution and competition for paternity in X. inauris is sperm competition. I find evidence that investment in sperm competition is costly and may reflect immunocompetence. I quantify reproductive …


An Assessment Of Sea Turtle Nesting Behavior In Relation To Hurricane- And Restoration-Induced Beach Morphodynamics, Tonya Michele Long Jan 2010

An Assessment Of Sea Turtle Nesting Behavior In Relation To Hurricane- And Restoration-Induced Beach Morphodynamics, Tonya Michele Long

Electronic Theses and Dissertations

Coastal habitats are highly dynamic and vulnerable to landscape-level disturbances such as storms and restoration projects. Along the east coast of Florida these areas are particularly valuable as they provide significant nesting habitat for two sea turtle species, the threatened loggerhead (Caretta caretta) and the endangered green turtle (Chelonia mydas). This coast was heavily impacted by three major hurricanes in 2004 and in some areas by large restoration projects in 2005. Recent remote sensing methods allow for broad evaluation of the shoreline and thus the ability to assess sea turtle nesting habitat at a landscape scale. I collected nesting data …


Species Composition And Spatiotemporal Pattern Of The Seed Bank And Vegetation In Native And Degraded Florida Rosemary Scrub, Jennifer J. Navarra Jan 2010

Species Composition And Spatiotemporal Pattern Of The Seed Bank And Vegetation In Native And Degraded Florida Rosemary Scrub, Jennifer J. Navarra

Electronic Theses and Dissertations

The soil seed bank plays a dynamic role in the regeneration of plant communities after natural and anthropogenic disturbance. In this thesis, I addressed how disturbances influence the vegetation and seed bank of Florida rosemary scrub. In Chapter One I evaluated changes in species composition and spatiotemporal pattern of the vegetation and seed bank along a gradient of disturbance. During the summers and winters of 2007-2009 percent ground cover and seed bank species composition were assessed among replicates of three vegetation types subjected to minimal, moderate, and extreme anthropogenic disturbance (native rosemary scrub, degraded scrub, and agriculturally improved pasture, respectively). …