Ecology and Evolutionary Biology Commons^™

Evolutionary Mechanisms For Host Resistance To Tumor Growth And Subsequent Cancer Cell Counter-Adaptations, Arig Ibrahim Hashim

USF Tampa Graduate Theses and Dissertations

Cancer is well-recognized as an evolutionary system, as first proposed by Cairns and Nowell more than 60 years ago. In an evolutionary context, cancers growing in vivo typically consist of heterogeneous subpopulations of cells that interact with each other and with host cells through selection forces operating at many temporal and spatial scales. Moreover, the tumor environment comprises more than just cancer cells; it includes a rich cancer stroma and cancer-driving molecules such as cytokines and metabolites. The tumor’s environment comprises intratumoral heterogeneity that often leads to therapy resistance attributed to the essential roles of many genetic and nongenetic mechanisms. …

Synthesis Of A Multimodal Ecological Model For Scalable, High-Resolution Arboviral Risk Prediction In Florida, Sean P. Beeman

USF Tampa Graduate Theses and Dissertations

West Nile virus (WNV) and Eastern Equine Encephalitis virus (EEEV) represent the two greatest endemic arboviral risks to the state of Florida. Currently, no approved human vaccine exists for the prevention of either virus. In the absence of a vaccine, effective disease surveillance is paramount for public health. In Florida, WNV and EEEV sentinel chicken surveillance is conducted by mosquito control programs operated at the county, municipality, or special taxing district level. This program was implemented in 1978 following human outbreaks of St. Louis Encephalitis virus (SLEV) that occurred between 1959 and 1977, with initial sentinel coops placed in proximity …

The Effects Of Agrochemical Pesticide Applications On Target And Off-Target Species In Aquatic Ecosystems, Bryan K. Delius

USF Tampa Graduate Theses and Dissertations

The increase in the global human population is driving agricultural expansion, which increases the likelihood and degree by which agrochemicals impact aquatic systems. It is projected that by 2100 the global human population will exceed 11 billion, and to feed the increased human population, the necessary increase in agricultural infrastructure is estimated to double irrigation, nearly triple fertilizer applications, and increase pesticide applications by tenfold. It stands to reason that wetlands impacts from agriculture are also likely to increase as the industry expands its operation to meet the globally growing demand for food.

Wetlands are highly productive habitats that not …

Architectural Complexity Of Oyster Reefs: Evaluating The Relationship Between Interstitial Spaces And Macroinvertebrates, Elizabeth A. Salewski

USF Tampa Graduate Theses and Dissertations

Understanding how organisms utilize and interact with habitat features may improve predictions of habitat preferences and species interactions, and may assist in the development of conservation and management strategies. The architecture of a habitat provides a complex array of structural features that influences interactions between the abiotic and biotic factors, and impact the biodiversity and species abundance through altering recruitment patterns and the survival of associated fauna. Characterizing potential refugia however has been challenging with minimal attempts to measure interstitial space size and abundance in reef systems. Here, I present novel methodology utilizing 3D technology to characterize interstitial spaces within …

Epigenetic Potential In An Introduced Passerine, Haley E. Hanson

USF Tampa Graduate Theses and Dissertations

Epigenetic modifications play a critical role in numerous processes throughout the lifetime of an organism by influencing gene regulation. Responsive to both endogenous cues and external stimuli, epigenetic modifications are key mechanisms underlying phenotypic plasticity. Epigenetic potential, or the capacity for phenotypic plasticity mediated by epigenetic modifications, can be encoded within the genome via genetic variation underlying aspects of epigenetic modifications. For example, one type of epigenetic modification, DNA methylation, predominately occurs at CpG motifs in vertebrates. The number of CpG sites within the genome then represents the capacity for DNA methylation to occur and is one form of epigenetic …

Mechanisms And Mitigation: Effects Of Light Pollution On West Nile Virus Dynamics, Meredith E. Kernbach

USF Tampa Graduate Theses and Dissertations

Light pollution, or the presence of unnatural light at night, is a pervasive and growing problem across the globe. While often pictured in urban centers, light pollution is far reaching and can affect seemingly safe and minimally developed environments. For example, agricultural communities with artificial lighting near facilities can generate such light pollution in rural areas. Further, streetlights and illuminated billboards along roads and highways can generate light pollution far from cities. Given how pervasive this anthropogenic stressor is, it is surprising that not much is known about how artificial light at night, or ALAN, affects humans or wildlife, especially …

The Distribution In Native Populations From Mexico And Central America Of The C677t Variant In The Mthfr Gene, Lucio A. Reyes

USF Tampa Graduate Theses and Dissertations

Objectives: To explore evolutionary hypotheses for the high frequencies of a substitution in the methylenetetrahydrofolate reductase (MTHFR) gene, in Mexican and Central American Indigenous populations.

Materials and methods: We obtained allele frequencies for the C677T variant in the MTHFR gene and ecological information for 37 indigenous samples from Mexico and Central America. We calculated Hardy–Weinberg equilibrium and computed Fst statistics. We computed correlations between the samples' allele frequencies and ecological and geochemical variables.

Results: Many of the samples have extremely high frequencies of the T allele (q̄ = 0.62, median = 0.66). In this region, the frequency of the T …

Shorebird Response To Human-Induced Changes At Three Pinellas County Beaches, Rebecca J. Ruthberg-Campagna

USF Tampa Graduate Theses and Dissertations

Worldwide, shorebird habitat is being destroyed and degraded by development and sea level rise. Shorebirds depend on availability of pristine, undisturbed coastal habitats for resting and feeding during migration as well as for reproduction. Migratory shorebirds using the East Atlantic Flyway visit the Gulf of Mexico Beaches of Pinellas County, Florida as a stopover site during Fall and Spring migration. In addition to hosting migratory species, Pinellas County beaches are home to several year-round resident species that breed during Summer. Pinellas County is the most densely populated county in Florida, and its Gulf Coast is heavily developed with commercial and …

The Impact Of Bahiagrass (Paspalum Notatum) On Florida Sand Skink (Plestiodon Reynoldsi) Movements, Chandler A. R. Eaglestone

USF Tampa Graduate Theses and Dissertations

The Florida Sand Skink (Plestiodon reynoldsi) is a federally threatened lizard precinctive to scrub habitat, a pyrogenic habitat that experiences fires infrequently. Plestiodon reynoldsi spends most of its time right under the sand surface, moving, or “sand swimming,” through the granular substrate found in Florida’s central ridges. While the distribution of this species has been greatly reduced, agricultural development of P. reynoldsi habitat has led to potentially suitable fragmented scrub occurring near bahiagrass (Paspalum notatum) pastures. Bahiagrass is widely used as a pasture grass in sandy soils of the southeast United States, because of its deep …

Modeling Early Life: Ontogenetic Growth And Behavior Affect Population Connectivity In Gulf Of Mexico Marine Fish, Kelly Vasbinder

USF Tampa Graduate Theses and Dissertations

This dissertation is an examination of growth, behavior, and dispersal during the early life stages of marine fishes in the Gulf of Mexico. Understanding movements of early life stages is a key part of managing exploited fish populations. Position in the water column can impact larval dispersal, since it determines those currents to which larvae are exposed. First, I investigated the relationship between length and age in early life stages of marine fishes. I found that demersal fish taxa tend to be represented by exponential models, while pelagic fish tend to be represented by linear models. I suggest this may …

Cross-Host Correlations And Multivariate Effects Of Herbivore Specialization, Daniel J. Zydek

USF Tampa Graduate Theses and Dissertations

The distribution of insect herbivores among plant hosts is largely nonrandom: most herbivores have limited sets of hosts within one or a few plant families. This host use specialization is reinforced by traits that confer differential fitness across host plant species. Classic explanations for herbivore specialization predict that evolutionary trade-offs reinforce these relationships by imposing costs in the form of reduced potential fitness on alternative hosts, due to negative genetic correlations in fitness across hosts. This prediction that trade-offs constrain host use in herbivores can be tested with experimental evolution, by showing the direct evolutionary effects of host manipulation on …

Environmental Influences On Expression Of Virulence- And Survival-Associated Genes And Epigenetic Modifications Of Dna In Vibrio Vulnificus, James W. Conrad

USF Tampa Graduate Theses and Dissertations

Vibrio vulnificus is an autochthonous inhabitant of warm, brackish coastal waters and is an opportunistic pathogen that causes the highest mortality of all seafood-related illnesses (1). These fatal infections are generally caused by the clinically-associated vcgC/16S rRNA type B genotypes within the biotype I group (2–5). However, the reasons for the heightened infectiousness of the clinically-associated strains over environmentally-associated ones remains elusive, as no unique clinically-associated virulence genes have been identified through genomic sequencing or other strategies. DNA methylation may contribute to regulation of virulence by affecting gene transcription, and was investigated in the highly virulent V. vulnificus strain CMCP6. …

Reproduction And Parasite-Mediated Selection, Meredith A. Krause

USF Tampa Graduate Theses and Dissertations

Sexual reproduction generates genetic diversity that can help hosts respond to selection by parasites, and in this thesis, I test three predictions on how reproduction impacts predictions by the parasite theory of sex and the Red Queen hypothesis. In Chapter one, using a meta-analysis, I found that asexuals (lower genetic diversity) have more parasites than sexuals (higher genetic diversity), but this difference can be heavily mediated by the mode and origin of asexuality. Further, hybridization but not polyploidy can blunt predicted differences in parasite loads among sexual and asexual hosts. In Chapter two, I flip the perspective of Red Queen …

Feeding Specificity Of The Photosynthetic Sacoglossan Sea Slug Elysia Papillosa, Kourtney Sui Barber

USF Tampa Graduate Theses and Dissertations

The sacoglossan sea slug, Elysia papillosa is associated with two species of the siphonaceous green alga, Penicillus, which co-occur in mixed macrophyte beds at Tarpon Springs, FL, USA. Field collections revealed that Elysia papillosa is frequently collected from the alga, P. capitatus, but is also present in much lower abundance on P. lamourouxii. Past studies have shown that some species of sacoglossans consume algal species that differ from the algae from which they are collected so, in order to determine whether E. papillosa was consuming either or both species of Penicillus, total DNA was extracted from individual slugs collected from …

Effects Of Inter-Male Status Challenge And Psychopathic Traits On Sexual Aggression, Amy M. Hoffmann

USF Tampa Graduate Theses and Dissertations

Sexual aggression (SA) is a serious social problem that has been linked to a variety of negative physical and mental health outcomes for survivors and produces significant monetary costs to society. In the past five decades, a wealth of research has improved our understanding of the individual and sociocultural factors that contribute to SA perpetration; however, epistemological differences in theoretical approaches to the subject (i.e., evolutionary, feminist) have resulted in gaps in the empirical literature. Informed by both feminist and evolutionary perspectives, this study attempts to examine the ways in which same-gender interpersonal interactions and individual psychopathology interact to produce …

Microbial Community Structures In Three Bahamian Blue Holes, Meghan J. Gordon

USF Tampa Graduate Theses and Dissertations

This study used 16S rDNA metagenomics and water chemistry to conduct an examination of microbial community dynamics and biogeochemistry in three physically adjacent, sunlit blue holes with variable hydrologic regimes on San Salvador Island, Bahamas. Church and Watling’s Blue Holes are holomictic with relatively clear waters, while Inkwell Blue Hole hosts density stratification and waters stained brown with tannins. Based on water color and clarity and physicochemical profiles, I hypothesized Church and Watling’s Blue Holes would be dominated by oxigenic photoautotrophs, and that the bottom layer of Inkwell would be characterized by euxinic (anoxic and sulfidic) conditions and host primarily …

Biogeochemical Cycling Of Nutrients And Carbon In Subtropical Wetlands, Lauren N. Griffiths

USF Tampa Graduate Theses and Dissertations

As human development intensifies, ecosystems around the word are being exponentially destroyed and degraded. Wetlands have the capacity to mitigate some of the possible problems by retaining nutrients and carbon, keeping them from harming downstream ecosystems or being released into the atmosphere. This project focuses on the processes that make wetlands successful by studying two unique ecosystems: 1) a created urban stormwater treatment wetland and 2) mangrove wetlands in Florida and Puerto Rico that were affected by hurricanes in 2017.

The first phase of this study investigates the role of sedimentation and vegetative and algal uptake of nutrients to retain …

The Ecology And Conservation Of An Urban Karst Subterranean Estuary, Robert J. Scharping

USF Tampa Graduate Theses and Dissertations

Sulphur Springs is an artesian spring and part of the limestone karst topography of metropolitan Tampa, Florida, USA. Underlying this spring is an extensive cave system that hosts saltwater vents and conspicuous microbial biofilm communities. For decades, water from Sulphur Springs has been extracted and used to supplement public water supply and dry season flows in the Hillsborough River Estuary. This dissertation describes research conducted at Sulphur Springs to determine the impacts of urban land use on the underlying cave and downstream estuary ecosystems, and presents the use of this system as a model to fill certain ecological knowledge gaps. …

Isotope-Based Methods For Evaluating Fish Trophic Geographies, Julie L. Vecchio

USF Tampa Graduate Theses and Dissertations

Data on the movement and diets of fish during a variety of life stages are important inputs to fisheries stock assessments and marine ecosystem models. Stable isotopes may provide previously inaccessible information on movement and diet of a variety of managed and forage fish species. Here I used several novel means of interpretation for stable isotope data to infer diets and movements of several important fisheries species over both short (weeks to months) and long (lifetime) timescales. To calculate a constant partitioning offset (CPO) between the δ¹⁵N of muscle and of liver tissue, I conducted a literature search …

Springs Of The Arabian Peninsula: Historical Trends, Current Status And Human Impact In Saudi Arabia, Oman And Jordan, Kamal M. Aljohani

USF Tampa Graduate Theses and Dissertations

This research was conducted to update previous studies of the springs of the Arabian Peninsula (Saudi Arabia, Oman and Jordan). Approach: 76 springs were surveyed in between March and July 2018: 15 Saudi Arabia, 41 Oman and 20 Jordan to ascertain the current status, water quality and zooplankton benthos and fish communities. Investigation of the changes of biota and chemical parameters downstream from the springs source in Saudi Arabia. Results: Mercury exceeded the WHO and USEPA maximum contaminant level (MCL) in 63 of 76 springs, Aluminum exceeded MCL in 8 of 76 springs, and both were the common dissolved heavy …

Ecological Responses Of Seascape Heterogeneity, Dinorah H. Chacin

USF Tampa Graduate Theses and Dissertations

A core aim of landscape ecologists as well as conservation and management practices has been to understand how processes that structure communities vary as a function of landscape context. Landscape heterogeneity (i.e. landscape composition, configuration) and fine-scale habitat characteristics can influence ecological interactions across habitat patches at a range of scales. Therefore, the main objective of this work is to apply a landscape ecology perspective to understand how seascape heterogeneity can influence demographic rates, community patterns, and ecological processes. To accomplish this overall goal, I conducted a literature review on oyster reefs from a seascape ecology perspective (Chapter 1) and …

The Peculiar Nature Of Florida’S Sandhill Wetlands, Ponds & Lakes— Their Ecohydrology, Relationship With The Regional Aquifer & Importance Within The Landscape., Renae Starr Nowicki

USF Tampa Graduate Theses and Dissertations

This dissertation explores the ecohydrology of Florida’s peculiar and poorly studied sandhill wetland and water features, particularly those located in west-central Florida. The primary research goals include: compilation and summarization of the available ecohydrologic information for features across Florida; comparison of water level and water geochemistry data between sandhill wetlands and waters and the regional aquifer to provide evidence of regional hydrologic control; and use of geophysical applications to examine the hydraulic connections between sandhill wetlands and waters and the regional aquifer.

From this research, a natural history of sandhill wetland and water ecohydrology is presented, highlighting: the differences between …

Untapped Potential Of Gorgonian Octocorals For Detecting Environmental Change In Biscayne National Park, Florida, Usa, Selena A. Kupfner Johnson

USF Tampa Graduate Theses and Dissertations

One consequence of dramatic stony-coral loss has been recognition that gorgonian octocorals (Anthozoa: Octocorallia) have emerged among the dominant reef fauna. However, gorgonians are notoriously difficult to field-identify and consequently have been underrepresented in most monitoring efforts resulting in a lack of long-term data. The rich diversity of habitats, close proximity to the urban center of Miami, and connectivity to other areas of Florida have made Biscayne National Park an active location for reef research since its establishment in 1968. As such, a plethora of data (e.g., museum specimen and species abundance data) has been collected and stored in archives …

Investigating Among-Individual Growth Heterogeneity In Longleaf Pine: Advancing Dendrochronological Approaches, Jamie E. Munn

USF Tampa Graduate Theses and Dissertations

Within a population, individuals frequently differ in the rate at which they grow, and this rate can be impacted by both genetic differences and abiotic factors. Often, dendrochronology is used to elucidate growth trends based on climate or other factors. This dissertation explores new statistical approaches to dendrochronological research.

First, I created a chronology for a population of longleaf pine (Pinus palustris P. Mill.) individuals in a southwest Florida sandhill community. I then used generalized linear mixed models to investigate the effects of fire frequency, year, tree age and size, and elevation on variation in radial growth heterogeneity. I then …

Evaluating The Effect Of Temperature On A Human Parasite And Its Intermediate Snail Host: Implications For A Changing Climate, Karena H. Nguyen

USF Tampa Graduate Theses and Dissertations

Global climate change is impacting the emergence, re-emergence, prevalence, and incidence of infectious diseases worldwide, including parasitic diseases of humans (Blum and Hotez 2018). Neglected tropical diseases, defined as a group of parasitic diseases affecting developing countries in the tropics (Hotez et al. 2007), are of particular concern because these diseases occur in areas that are also expected to experience rapid population growth and agricultural development in the coming decades. As human population and food demand increase, the greater the likelihood of humans encountering intermediate hosts that either inhabit agricultural areas or are impacted by agricultural development, which will influence …

Design And Implementation Of Degenerate Qpcr/Qrt-Pcr Primers To Detect Microbial Nitrogen Metabolism In Wastewater And Wastewater-Related Samples, Ryan F. Keeley

USF Tampa Graduate Theses and Dissertations

Nitrogen cycling processes can be tracked using quantitative Polymerase Chain Reaction (qPCR) to determine the presence and qReverse Transcriptase-PCR (qRT-PCR) to determine expression of key genes, or ‘biological markers’, for nitrogen metabolism. Nitrification is catalyzed in part, by two enzymes: ammonia monooxygenase (AMO; NH3 NH2OH) and nitrite oxidoreductase (NXR; NO2- NO3-). For denitrification, four enzymes act sequentially: nitrate reductase (NAR/NAP; NO3- NO2-), nitrite reductase (NIR; NO2- NO), nitric oxide reductase (NOR; NO  N2O), and nitrous oxide reductase (NOS; N2O  N2). A principle of wastewater treatment (WWT) is to remove excess nitrogen by taking advantage of natural nitrogen cycling …

Stable Isotope Geochemistry Of Shelled Marine Invertebrates: Wide-Ranging Applications, Nasser M. Al-Qattan

USF Tampa Graduate Theses and Dissertations

Mollusks grow by adding discrete growth layers throughout their lifetime (i.e., accretion). More specifically, most marine mollusks precipitate their shells in oxygen isotopic equilibrium with seawater or with a constant offset from equilibrium. The stable oxygen isotope values (δ¹⁸O) of their shells are determined by the temperature and δ¹⁸O values of the surrounding water during calcification without significant vital effects. In comparison, the stable carbon isotope values (δ¹³C) of their shells reflect those of the dissolved inorganic carbon (δ¹³C- DIC) and respired carbon dioxide. Therefore, variations in the oxygen and carbon isotope …

An Investigation Of The Effects Of The Parasitic Nematode Aplectana Hamatospicula On The Performance And Behavior Of Cuban Treefrogs (Osteopilus Septentrionalis), Kerri Surbaugh

USF Tampa Graduate Theses and Dissertations

Parasitic infections are ubiquitous in nature, and host-parasite dynamics can have powerful effects on wildlife populations. Many species have evolved behavioral responses to infection that can help mitigate damage from parasites. Anorexia is a common response to infection observed throughout the animal kingdom. Reducing nutrient intake can help shift host resources from digestion to immunity, as well as limit resources available to parasites. Reduced feeding can weaken the host, but in some host-parasite interactions, this cost is less than that of maintaining an infection. Here, I describe an experiment aimed to explore the effects of the parasitic nematode Aplectana hamatospicula …

Habitat Suitability Index Model Of The Florida Sandhill Crane (Grus Canadensis Pratensis) In West-Central Florida, Courtney E. Buck

USF Tampa Graduate Theses and Dissertations

The Florida Sandhill Crane (Grus canadensis pratensis) is a state threatened endemic subspecies of the Sandhill Crane (Nesbitt & Tacha, 1997). With a population that was estimated at a maximum of 5,000 individuals in 2003 (Nesbitt & Hatchitt, 2008), it is imperative to identify potentially viable habitats, as Florida is rapidly developing. This research develops a Habitat Suitability Index model to determine unsuitable to optimally suitable habitat locations throughout west-central Florida. To do so, six suitability variables based on the crane’s life history were evaluated: Potential nesting area, immediate nesting area, wetland coverage, foraging area, brooding area, and road proximity. …

Density-Mediated Interactions Are Stronger But More Variable Than Trait-Mediated Interactions In Predator–Prey Systems, Travis M. Flock

USF Tampa Graduate Theses and Dissertations

Theoretical and empirical considerations of predator-prey dynamics have sought to determine the dominant of two effects exerted by predators onto prey: consumptive effects of predators and non-consumptive, or trait-mediated, effects. Many studies have identified trait-mediated interactions (TMIs) in diverse taxa, and meta-analyses of these studies found that prey population dynamics are as strongly – if not more strongly – affected by TMIs as density-mediated interactions (DMIs). Since then, there is now an expanded primary literature, and given this potential for new insight on the direct and indirect effect of predators on prey, the cost of traits involved in TMIs relative …