Ecology and Evolutionary Biology Commons^™

Investigating Students' Interpretations Of Ecological Food Webs, Christopher Neil Grissett

USF Tampa Graduate Theses and Dissertations

To better prepare undergraduate students for current and future biological challenges, scientists, educators and researchers in the Vision and Change report recommended five core conceptual areas essential for the improvement of biological literacy, one of which is biological systems. Systems are an identified core concept that may help promote biological literacy. One example of a system that students have difficulty understanding is an ecological food web, which consists of parts or components interacting with one another to perform a given phenomenon. The intricacies of this system tend to confuse students and can produce naïve conceptions that could hinder future learning …

Quantitative Assessment Of The Trophic Ecology Of The Oceanic Ctenophore, Bolinopsis Infundibulum, In Monterey Bay, California, Victoria C. Scriven

USF Tampa Graduate Theses and Dissertations

Bolinopsis infundibulum is a wide-ranging, ubiquitous ctenophore whose fragile nature makes the collection of specimens and quantification of key predator-prey activities in controlled laboratory experiments, challenging. Thus, in situ methods often represent the best means for data collection. However, while present in surface waters, these animals can also be abundant at depths well beyond those attainable by divers. As a result, very little empirical data exist over the depth range of their natural habitats which limits our ability to assess key predator-prey interactions needed to assess their ecological role in midwater food webs. Working in Monterey Bay, California, remotely operated …

The Ecological Role Of Cassiopea In Shallow Mangrove Habitats, David Marcel Durieux

USF Tampa Graduate Theses and Dissertations

Upside-down jellyfish, Cassiopea sp., can be locally abundant in shallow mangrove habitats throughout the tropics and subtropics. Unlike other jellyfish, Cassiopea sp. are epibenthic. Due to this unique lifestyle and their ability to achieve high population densities, an understanding is needed of their ecological impacts both individually and in aggregations, particularly given that Cassiopea sp. ranges are expanding poleward due to global climate change. We quantified the fluid flow produced by Cassiopea sp. feeding currents and found that an average-sized Cassiopea sp. can transport over 200 l/h of water in the vertical excurrent jet of their feeding current. Populations of …

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. …

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 …

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 …

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 …

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 …

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 …

Measuring Flowering Phenology And Its Consequences: A Systematic Review, Samantha M. Mangum

USF Tampa Graduate Theses and Dissertations

Despite growing interest in flowering phenology among ecologists, as reflected by an increase in the number of papers, there is little information on how studies typically measure and describe a plant’s flowering phenology. The focus of this study was the literature on flowering phenology and the approaches researchers have taken to quantify flowering phenology. Initially, a comprehensive description of the breath of literature on flowering phenology was produced. From there, I described the current research on flowering phenology: the year that the studies were published, the locations of the studies, and the particular biomes where the studies were performed. The …

Behavioral Thermoregulation And Thermal Mismatches Influence Disease Dynamics In Amphibians, Erin Louise Sauer

USF Tampa Graduate Theses and Dissertations

Amphibians are currently the most threatened vertebra taxa on the planet. Hundreds of species are thought to have gone extinct while thousands more have been listed as threatened or endangered over the past few decades. Habitat loss, invasive species, climate change, and disease are all thought to have partially contributed to these declines. Two pathogens in particular, infectious viruses in the genus Ranavirus (simply referred to as ranavirus) and the fungus Batrachochytrium dendrobatidis (Bd), have been associated with global mass mortality events of amphibians. Virulent pathogens such as these tend to impose strong selective pressures on their hosts driving the …

Use Of A Towed Camera System Along The West Florida Shelf: A Case Study Of The Florida Middle Grounds Benthic Marine Communities, Katie S. Davis

USF Tampa Graduate Theses and Dissertations

As technologies advance the study of ocean dynamics, new approaches to vexing problems of scale and process are becoming more widely available. Originally conceived as a tool primarily for indexing the abundance of near-bottom fishes, the Camera-based Assessment and Survey System (C-BASS) may also be an effective tool for monitoring benthic invertebrate resources vulnerable to natural and anthropogenic perturbations, and for characterizing the composition of benthic communities to inform spatial management. Using still images derived from the C-BASS video of benthic transects within the Florida Middle Grounds, I documented the abundance of benthic habitat-forming functional groups—sponges, algae, and corals—and noted …

Intraspecific Variation In The Recruitment Dynamics Of A Transgressing Avicennia Germinans Population, Shannon Victoria Grogan

USF Tampa Graduate Theses and Dissertations

Survival and establishment of mangrove propagules at higher tidal elevations beyond the landward margin of their distribution is a requirement for the continued existence of mangrove populations in response to rising sea-level. Despite the growing body of literature that discusses mangrove recruitment patterns, few studies have empirically examined establishment and post-establishment growth success of propagules at the higher intertidal positions into witch mangrove populations are migrating. Using an experimental field approach, this study compares establishment and post-establishment growth success of propagules at three positions across a tidal elevation gradient within a landward-transgressing mangrove population of SW Florida (USA). I observed …

Molecular Phylogenetics Of Floridian Boletes, Arian Farid

USF Tampa Graduate Theses and Dissertations

The boletes are macrofungi which have undergone extensive taxonomic revisions since the advent of molecular tools. To further our understanding of the boletes in peninsular Florida, we sequenced two common Floridian boletes, and analyzed them with molecular phylogenetic tools. Boletus rubricitrinus, a common Florida bolete often found in lawns under Quercus, and likely has a distribution that extends to Texas. Based on ITS and LSU sequences and morphological studies, this species belongs in the genus Pulchroboletus. As the holotype is in poor condition, an epitype is established here. A thorough description of macroscopic and microscopic features is also provided for …

Grooming Behaviors Of, Lauren N. Williams

USF Tampa Graduate Theses and Dissertations

The giant freshwater shrimp, Macrobrachium rosenbergii is a large species of prawn grown extensively in aquaculture settings. A social hierarchy exists within the males of this species, representing three distinct male morphotypes. These male morphotypes differ in their behavior, physiology, and morphology and include the largest blue-clawed males (BC males), moderately- sized orange-clawed males (OC males), and the undifferentiated small-clawed males (SM males). All individuals of this species perform grooming behaviors to rid themselves of body fouling which can impede important functions such as movement, respiration, chemoreception, and reproduction. Grooming behaviors in crustaceans often utilize specialized structures called setae, which …

Ecosystem Function And Phenotypic Variation In Spartina Alterniflora Salt Marshes, Sandra E. Voors

USF Tampa Graduate Theses and Dissertations

Biodiversity is important to ecosystem function at many scales, and variation functional traits within a species can potentially influence ecosystem functioning by altering nutrient cycling dynamics. High population extinction rates are resulting in a rapid loss of within-species biodiversity, so there is a need to better understand the importance of intraspecific variation to ecosystem-level processes. Tidal salt marshes are ideal ecosystems for investigating intraspecific variation in plant-nutrient relationships because they are dominated by a monoculture of the foundation species Spartina alterniflora, with distinct phenotypes that correspond to environmental gradients across the marsh. We conducted a field survey of existing …

Ecological Epigenetics Of Avian Range Expansions, Holly J. Kilvitis

USF Tampa Graduate Theses and Dissertations

In light of human-mediated environmental change, a fundamental goal for biologists is to determine which phenotypic characteristics enable some individuals, populations or species to be more adept at coping with such change, while rendering others more vulnerable. Studying ongoing range expansions provide a unique opportunity to address this question by allowing documentation of how novel environments shape phenotypic variation on ecological timescales. At range-edges, individuals are exposed to strong selective pressures and population genetic challenges (e.g. bottlenecks and/or founder effects), which make genetic adaptation difficult. Nevertheless, certain species, such as the house sparrow (Passer domesticus), seem to thrive in their …

Bioleaching Potential Of Filamentous Fungi To Mobilize Lithium And Cobalt From Spent Rechargeable Li-Ion Batteries, Aldo Lobos

USF Tampa Graduate Theses and Dissertations

Demand for lithium (Li) and cobalt (Co) is on the rise, due in part to their increased use in rechargeable Li-ion batteries (RLIB). Current recycling processes that utilize chemical leaching efficiently recover in Li and Co from the cathode material in spent batteries; however, these processes are costly and emit hazardous waste into the environment. Therefore, a more sustainable process for recycling Li and Co is needed, and bioleaching may provide a solution. Fungal bioleaching has been shown in previous studies to effectively mobilize metals (Pb, Al, Mn, Cu, and Zn) from mine tailings, electronic scrap, and spent batteries with …

Reef Fish Biodiversity In The Florida Keys National Marine Sanctuary, Megan E. Hepner

USF Tampa Graduate Theses and Dissertations

The biological diversity of reef-fish in the Florida Keys National Marine Sanctuary (FKNMS) from 1999 – 2016 was evaluated in terms of abundance, biomass, species richness, evenness, Shannon diversity, Simpson diversity, and functional diversity, using observations collected by multiple agencies and institutions under the Reef Visual Census (RVC) program. To compare the different diversity indices species richness, Shannon diversity, Simpson diversity, and functional diversity were converted into effective number of species. I examined the seven indices by no-take marine zones, in seven benthic habitat strata, and across the three-distinct geographic subregions in the Florida Keys domain (Upper, Middle, and Lower …

Response To Nitrogen And Salinity Conditions In Rhizophora Mangle Seedlings Varies By Site Of Origin, Kristen L. Langanke

USF Tampa Graduate Theses and Dissertations

Many coastal plant species thrive across a range of environmental conditions, often displaying dramatic phenotypic variation in response to environmental variation. We characterized the response of the critical foundation species Rhizophora mangle L. to full factorial combinations of salt and nitrogen (N). We used seedlings collected from five populations and measured traits related to salt tolerance and N amendment. The response to increasing salt included significant plasticity in succulence, leaf mass area (LMA), and root to shoot ratio (R:S). Seedlings also showed overall reduced maximum photosynthetic rate in response to N amendment, but this response depended on the level of …

Spatial And Temporal Variation In Mangrove Distribution (1950-2014) In Tampa, Florida Usa, Carolyn Cheatham Rhodes

USF Tampa Graduate Theses and Dissertations

I carried out an observational study of historic high resolution aerial imagery spanning six decades (1950-2014) to identify recent and historic spatial extent of mangrove forests, within the municipal boundaries of the City of Tampa, Florida USA. My objectives were to map mangrove distribution and spatial extent and any change or patterns of change discernable. I observed variable patterns of change and rates of expansion varied between sites spatially as well as within sites between time intervals. I found notable changes in mangrove extent in the Tampa from historic and modern aerial imagery for the ~64-year period between 1950 and …

Epigenetic Response To Challenging Environmental Conditions, Marta Robertson

USF Tampa Graduate Theses and Dissertations

The discovery of epigenetic mechanisms has ignited speculation into their role in ecological and evolutionary processes. In particular, the contribution of epigenetic variation to adaptation or phenotypic plasticity that is distinct from genetic variation would be an important addition to existing evolutionary mechanisms. Although the research of epigenetic mechanisms from an ecological and evolutionary (or eco-evolutionary) perspective has been growing, it is still unclear how epigenetic variation might function in natural populations and settings and to what extent it might serve to mediate population response to changing environmental conditions over time. Over the course of my dissertation, I explored the …

Taxonomy, Ecology, And Behavior Of The Kleptoplastic Sea Slug Elysia Papillosa, William Alan Gowacki

USF Tampa Graduate Theses and Dissertations

Sacoglossan sea slugs are one of the best known examples of specialist herbivores in the marine environment and can be found strongly associated with their algal hosts and food sources. Perhaps the most intriguing characteristic of many sacoglossans is their ability to sequester functional chloroplasts from their algal food sources in a process called kleptoplasty. Despite this, there continues to be issues regarding taxonomic identification of species. In turn, the ecological characteristics of many of these slugs, such as algal host and food source preference, as well as their behavioral aspects, have received little attention. A prime example of these …

Zonation Pattern And Spatial Arrangement Of A Geukensia Granosissima Population In A Mixed Mangrove Forest Of Tampa Bay, Derrick Shane Hudson

USF Tampa Graduate Theses and Dissertations

Here I provide the first report on Geukensia granosissima patterns of abundance along a tidal gradient within a mixed mangrove stand located in Tampa Bay, Florida, USA. Specifically, I examined 1) the relationship between G. granosissima size and density with mangrove root type (e.g. prop root, pneumatophore), and of density within the intertidal zones; and 2) the possible role of predation in shaping the lower zonation patterns displayed. Transect surveys located along the lower and upper population limit boundaries were conducted every two months over a ten-month period. Variables measured include size distribution, density of mussels, above ground mangrove prop …

Land Use, Stream Stability, And Benthic Invertebrates In A Dry Forest Watershed Of Western Costa Rica, Jacqueline Ann Demko

USF Tampa Graduate Theses and Dissertations

There is a paucity of data on dry forests, the most threatened biome in the tropics. The Nandamojo is a tropical dry forest watershed in Western Costa Rica that has been impacted by varying degrees of human induced modifications. This research was conducted to examine the influence of land use and channel characteristics on invertebrate communities within a sub basin of the Nandamojo watershed. This study addressed three hypotheses: (1) sites with low tree cover and small riparian buffer zones will have high erosion, (2) macroinvertebrate abundance will be lower at sites with low channel stability values, and (3) benthic …

Importance Of Forest Structure For Amphibian Occupancy In North-Central Florida: Comparisons Of Naturally Regenerated Forests With Planted Pine Stands, Christopher J E Haggerty

USF Tampa Graduate Theses and Dissertations

Once dominant, longleaf pine forests of the southeastern United States have been modified by 97 percent, resulting in several animal species being listed as endangered and threatened. Pine plantation silviculture (tree plantings) now occupies half of the original longleaf range where several animal species of conservation concern have experienced recent local population declines. In North America, the accepted practice of pine plantations is to plant pines densely in rows for wood production. Given that land use is considered a primary local driver for the 30% of amphibian species currently at risk of extinction, and planted pine is predicted to expand …

Drivers Of Immune Cost And Implications For Host Protection From Parasites, Amber Jasmine Brace

USF Tampa Graduate Theses and Dissertations

Among species, populations, and individuals, there exists a tremendous amount of variation in how hosts respond to, and are thus protected from parasites. Such variation inevitably affects host-parasite dynamics and ultimately how parasites will move through and evolve in communities. A likely factor in the diversity of immune responses seen in nature are the costs associated with activation of the immune system upon exposure to parasites. Costs can manifest in many ways, including changes in resource usage or metabolism, self-damage from inflammatory reactions, lost opportunities (e.g., foraging reproduction), and often as tradeoffs with other physiological processes. However, we do not …

From Tolerance To Transmission: Linking Within-Individual To Community-Level Disease Processes, Sarah Catherine Burgan

USF Tampa Graduate Theses and Dissertations

Hosts have two main strategies for coping with infections: resistance and tolerance. Resistance is aimed at preventing or eliminating parasites, whereas the goal of tolerance is to maintain performance regardless of parasite burden. The balance between resistance and tolerance within a host may mediate host competence, or the propensity of a host to infect other hosts or vectors. Hosts with high tolerance and low resistance to an infection, for instance, may be highly competent and possess the greatest potential to act as superspreaders. These superspreading hosts will contribute disproportionately to transmission, thus posing the greatest risk to other hosts within …

Comparison Of Gastropod Assemblages From Natural And Phosphate Mine Lakes Of Central Florida, William A. Mailand

USF Tampa Graduate Theses and Dissertations

Investigations were made examining the relationships between gastropod species richness and abundance across 20 phosphate and 20 natural lakes in Central Florida. In additional to lake category, age of phosphate lakes was used to determine if phosphate lakes ever approximate natural lakes. Additional physical, chemical, and biological parameters, including chlorophyll a, Ca, secchi, phosphorous, conductance, fish predation, and recreational lake use were investigated in order to determine if they affected gastropods with lake age. Comparisons were also made between gastropod species richness and average abundance and two groups of dominant vegetation categories: Panicum, a structurally complex macrophyte, and Typha …