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Computational Analysis Of Large-Scale Trends And Dynamics In Eukaryotic Protein Family Evolution, Joseph Boehm Ahrens

FIU Electronic Theses and Dissertations

The myriad protein-coding genes found in present-day eukaryotes arose from a combination of speciation and gene duplication events, spanning more than one billion years of evolution. Notably, as these proteins evolved, the individual residues at each site in their amino acid sequences were replaced at markedly different rates. The relationship between protein structure, protein function, and site-specific rates of amino acid replacement is a topic of ongoing research. Additionally, there is much interest in the different evolutionary constraints imposed on sequences related by speciation (orthologs) versus sequences related by gene duplication (paralogs). A principal aim of this dissertation is to …

The Effects Of Copper Exposure On Fish Locomotion And Predator-Prey Interactions, Tiffany N. Yanez

FIU Electronic Theses and Dissertations

This study determined the effects of the copper water quality criterion (WQC) by the EPA on [1] swimming performance and [2] predator-prey interactions of the Sailfin Molly, across a salinity gradient. Fish acclimated to FW (0 ppt) and 8-ppt saltwater were exposed to 11.3 and 8.44 µg/L Cu for 96 h, respectively. At the end of the exposures, fish swimming performance was determined by using the critical swimming speed, U_crit, the speed at which a fish cannot longer maintain position in the water column. U_critwas then measured again after a 4-week depuration period to determine if …

Factors Affecting Green Turtle Foraging Ecology Across Multiple Spatial Scales, Elizabeth Rose Whitman

FIU Electronic Theses and Dissertations

The hierarchical levels at which resource selection occurs can have important consequences for individual and population energy budgets and structure the impacts of a forager on its ecosystem. Assessing factors affecting resource selection of large marine herbivores across scales is important because of their potentially large impacts on seagrass community dynamics and historical and current changes in their population sizes and those of their potential predators. I explored the factors (predation risk, resource abundance, quality and identity) affecting resource use of large marine herbivores (green turtles, Chelonia mydas) from the scale of habitat patches to forage species within patches. …

Survival At The Summits: Amphibian Responses To Thermal Extremes, Disease, And Rapid Climate Change In The High Tropical Andes, Kelsey E. Reider

FIU Electronic Theses and Dissertations

Understanding biological responses to climate change is a primary concern in conservation biology. Of the ecosystems being rapidly impacted by climate change, those in the high-elevation tropics are among the most poorly studied. The tropical Andean biosphere includes record elevations above 5000 meters, where extreme environmental conditions challenge many organisms. In the Cordillera Vilcanota of southern Peru, frogs including Pleurodema marmoratum and Telmatobius marmoratus have expanded their ranges to 5244 – 5400 m into habitats created by glacial recession, making them among the highest recorded amphibians on Earth. To understand how hydrologic alterations from loss of glacial meltwater and climatic …

Habitat Use Of Three Abundant Predatory Fish Species In The Freshwater Marshes Of The Florida Everglades, Alex T. Ontkos

FIU Electronic Theses and Dissertations

The Florida Everglades presents a model setting for studying animal-habitat relationships in a dynamic landscape that is heavily influenced by seasonal hydrology and water management. I used dynamic, high-resolution habitat classification maps and radio-telemetry to examine habitat preference of Largemouth Bass, Bowfin, and Florida Gar before and after a field-scale manipulation was established to address uncertainties with Everglades restoration and water management practices. Results indicate preference for the canal habitat by all three species, which represents only a small portion of the submerged landscape even in the driest conditions. Bowfin and Florida Gar were more likely to be relocated within …

Spatial And Temporal Patterns Of Arctic Nearshore Fish Community And Food Web Structures, Mark B. Barton

FIU Electronic Theses and Dissertations

Climate change and increasing anthropogenic activities are causing rapid changes to environmental and ecological processes in the Arctic Ocean. To better understand these changes, scientists have increased research efforts in these regions, but to date the number of studies on Arctic nearshore habitats are lacking. My dissertation responds to the paucity of information and investigates patterns in Arctic nearshore fish communities and food webs to gain insight to how these ecosystems may shift as these changes continue. I used multivariate statistical analysis to examine patterns in community structure and composition to determine that Arctic nearshore fish communities are largely driven …

Quantitative Spatial Upscaling Of Categorical Data In The Context Of Landscape Ecology: A New Scaling Algorithm, Daniel Gann

FIU Electronic Theses and Dissertations

Spatially explicit ecological models rely on spatially exhaustive data layers that have scales appropriate to the ecological processes of interest. Such data layers are often categorical raster maps derived from high-resolution, remotely sensed data that must be scaled to a lower spatial resolution to make them compatible with the scale of ecological analysis. Statistical functions commonly used to aggregate categorical data are majority-, nearest-neighbor- and random-rule. For heterogeneous landscapes and large scaling factors, however, use of these functions results in two critical issues: (1) ignoring large portions of information present in the high-resolution grid cells leads to high and …

The Real Snowbirds Of South Florida: Using Citizen Science To Assess The Ranges Of South Florida's Overwintering Birdsh, Alexander V. Levine

FIU Electronic Theses and Dissertations

The overwintering ranges of North American bird populations are shifting and the winter ranges of south Florida’s landbirds remain understudied. Expert-drawn range maps used for scientific studies and environmental public policy could therefore be depicting inaccurate ranges for many migratory birds. This study used citizen science data from eBird (2001–2017) to evaluate patterns in overwintering avian species richness and identify discrepanciesin expert-drawn species range maps for overwintering passerines in south Florida. Most of Florida’s overwintering bird species were sighted in south Florida. Of the species observed there between 2001 and 2017, 66% had range map discrepancies. Fifteen target species were …

Evolutionary And Population Dynamics Of Crustaceans In The Gulf Of Mexico, Laura Timm

FIU Electronic Theses and Dissertations

Evolution occurs and can be conceptualized along a spectrum, bounded on one extreme by the relationships between deep lineages – such as phyla, classes, and orders – and on the other by the molecular dynamics of operational taxonomic units within a species, defined as population genetics. The purpose of this dissertation was to better understand the evolutionary and population dynamics of crustaceans within the Gulf of Mexico. In the second chapter of my dissertation, I provide a guide to best phylogenetic practice while reviewing infraordinal relationships within Decapoda, including the promise held by next-generation sequencing (NGS) approaches such as Anchored …

The Adaptive Evolution Of Herbivory In Freshwater Systems, Jessica Lynn Sanchez Montelongo

FIU Electronic Theses and Dissertations

Herbivory is thought to be nutritionally inefficient relative to carnivory and omnivory. But, herbivory evolved from carnivory in many lineages, suggesting that there are advantages to eating plants. To understand the adaptive significance of the transition from carnivory to herbivory, I proposed five hypotheses for the adaptive evolution of herbivory and reviewed the current freshwater literature to identify conditions where eating plants might be adaptive over eating animals. I tested three of these ideas (Suboptimal Habitat, Heterotroph Facilitation, and Lipid Allocation) using the herbivorous Sailfin Molly (Poecilia latipinna)and identified each as a potential mechanism for the evolution of …

Changes In Soil Microbial Functioning In Coastal Wetlands Exposed To Environmental Stressors And Subsidies, Shelby M. Servais

FIU Electronic Theses and Dissertations

Environmental perturbations are ubiquitous features of ecosystems and shape ecological structure and function. Climate change will alter the intensity and frequency of disturbances and expose ecosystems to novel combinations of useful inputs (subsidies) and harmful inputs (stressors). Coastal wetlands are particularly vulnerable to changing environmental conditions and are increasingly exposed to effects of interacting subsidies and stressors. In particular, the Florida Coastal Everglades, which has experienced accelerated change due to a history of water management practices, is vulnerable to new disturbances associated with climate change. The low-lying Florida Everglades faces multiple disturbances from storm surge, nutrient enrichment, and sea-level rise …

Linking Husbandry And Behavior To Enhance Amphibian Reintroduction Success, Luke Jack Linhoff

FIU Electronic Theses and Dissertations

Wildlife in captivity has a long history of benefiting global conservation goals. Captive animals can raise awareness and appreciation for the conservation of endangered species. Additionally, captive animals can be used as source populations to reintroduce animals back to the wild or to supplement existing wild populations. The rapid increase in amphibian species threatened with imminent extinction has necessitated the creation of dozens of captive-breeding programs. The focus of this dissertation has integrated topics across the spectrum of animals in captivity and the wild, and the results provide useful recommendations for conservation action. First, I describe how market pressures over …

Impact Of Herbivory, Structural Complexity, And Sediment On Caribbean Coral Reefs, Alain Duran

FIU Electronic Theses and Dissertations

The resilience of coral reefs depends, among others, upon local physical and biological characteristics. This dissertation focused on how herbivory, structural complexity, and sedimentation can impact the structure, function, and, ultimately, resilience of Caribbean coral reefs. We filled an important knowledge gap related to trophic niche and ecological roles of surgeonfishes (A. coeruleus and A. tractus), two of the most important herbivorous fishes in the Caribbean. We showed that both species feed primarily on turf algae preventing further progression of algal succession while A. tractus may also help reduce macroalgal abundance by targeting common macroalgal species such as …

A Confluence Of Invasion, Behavioral, And Theoretical Ecology: What Drives Ephemeral Metacommunity Re-Assembly?, Jesse Ryan Blanchard

FIU Electronic Theses and Dissertations

Metacommunity theory has been particularly useful in understanding the way spatially structured communities assemble. Both niche and neutral processes are known to influence metacommunity assembly, and the relative influence of each depends on the level of dispersal-limitation. Contemporary trait-based analyses of metacommunity assembly have enhanced our understanding of these processes. Of the traits investigated, individual personalities have received the least attention, but have been suggested to be drivers of metacommunity assembly model parameters, such as dispersal tendencies and patch density. I address this topic from three angles, three chapters, in this dissertation. First, I used a three-year field survey of …

Patterns Of Carbon Metabolism, Storage, And Remineralization In Seagrass Ecosystems, Jason Lee Howard

FIU Electronic Theses and Dissertations

Coastal marine sediments have recently been identified as globally important stocks of organic carbon (C_org) that, if compromised, could significantly exacerbate global greenhouse gas emissions. While resource managers and policy makers are eager to incorporate this ecosystem service into seagrass ecosystem valuation frameworks, similar to those already in existence for terrestrial forests, there has been insufficient information regarding how environmental conditions and seagrass ecology control carbon storage. These include the influence of the seagrass to the production and preservation of soil organic matter, the fate of stored carbon following conversion of coastal wetlands, and the interactions between organic …

Drivers And Mechanisms Of Peat Collapse In Coastal Wetlands, Benjamin J. Wilson

FIU Electronic Theses and Dissertations

Coastal wetlands store immense amounts of carbon (C) in vegetation and sediments, but this store of C is under threat from climate change. Accelerated sea level rise (SLR), which leads to saltwater intrusion, and more frequent periods of droughts will both impact biogeochemical cycling in wetlands. Coastal peat marshes are especially susceptible to saltwater intrusion and changes in water depth, but little is known about how exposure to salinity affects organic matter accumulation and peat stability. I investigated freshwater and brackish marsh responses to elevated salinity, greater inundation, drought, and increased nutrient loading. Elevated salinity pulses in a brackish marsh …

Recovery Of Amphibian And Reptile Communities During Tropical Secondary Forest Succession, Michelle E. Thompson

FIU Electronic Theses and Dissertations

The extensive clearing and modification of natural systems from anthropogenic activities is a pressing global concern. Forest habitats and animal communities within forests are among the most highly impacted, globally. Forest destruction has been repeatedly documented as a driver of biodiversity loss. However, little is known about how animal communities respond when altered landscapes are abandoned and left to regenerate into secondary forests. It is thought that the regrowth of secondary forests may help reverse biodiversity loss by restoring habitats to similar conditions as prior to land conversion. Of the forest cover that remains, over half is secondary forest, and …

Using Introduced Species Of Anolis Lizards To Test Adaptive Radiation Theory, James T. Stroud

FIU Electronic Theses and Dissertations

Adaptive radiation – the proliferation of species from a single ancestor and diversification into many ecologically different forms – has long been heralded as an important process in the generation of phenotypic diversity. However, the early stages of adaptive radiation are notoriously elusive to observe and study. In this dissertation, I capitalize on communities of introduced non-native Anolis lizards as analogues of early stage adaptive radiations. In Chapter II, I begin by reviewing the concept of “ecological opportunity” – a classic hypothesis put forward as a potential key to understanding when and how adaptive radiation occurs. In Chapter III, I …

A Historical Floristic Inventory Of Pine Rockland Fabaceae (Leguminosae), Adel L. Pena

FIU Electronic Theses and Dissertations

The objectives of this study were to investigate temporal changes in the diversity of pine rockland Fabaceae, induced by anthropogenic factors. Herbarium collections spanning 170 years were used to analyze species frequency and richness. The results indicated temporal fluctuations in diversity with frequency of native species highest previous to the year 1920, and exotic-invasive species richness peaking after the 1960s. The accompanying species list resulting from the inventory included 122 Fabaceae species, in 56 genera, with an additional 19 species not previously listed for pine rocklands. The results emphasize the damage caused by early and deliberate introductions of exotic species, …

Phenomenological And Molecular Basis Of The Cnidarian Immune System, Tanya Brown

FIU Electronic Theses and Dissertations

Coral reefs are one of the most diverse ecosystems on the planet due partially to the habitat structure provided by corals. Corals are long lived organisms that can live for hundreds of years and as a result growth of many species is very slow. As a result of this, recovery of corals from disease outbreaks is very slow and difficult and therefore the ecosystem is deteriorating rapidly. Due to this increase in disease and its detrimental effect on coral reefs, it has become imperative to study how corals respond to disease outbreaks. The response of the coral to pathogens is …

A Floristic Study Of Halmahera, Indonesia Focusing On Palms (Arecaceae) And Their Seed Dispersal, Melissa E. Abdo

FIU Electronic Theses and Dissertations

The dispersal services of frugivores affect plant community assembly, persistence, and gene flow in the short-term, and in the long-term are critical to ensuring that tropical trees and palms can regenerate in disturbed areas and can migrate amidst climate change. Halmahera is the largest Moluccan island within the Wallacea biodiversity hotspot, yet data on its plant and animal distributions and interactions are almost null. I studied the tropical trees and palms of Halmahera and their seed dispersal dynamics. Chapter I explores the palms of the Moluccan islands through field-, herbarium-, and literature- based studies. The results of herbarium specimen collections …

Reimagining Movements: Towards A Queer Ecology And Trans/Black Feminism, Gabriel Benavente

FIU Electronic Theses and Dissertations

This thesis seeks to bridge feminist and environmental justice movements through the literature of black women writers. These writers create an archive that contribute towards the liberation of queer, black, and transgender peoples.

In the novel Parable of the Talents, Octavia Butler constructs a world that highlights the pervasive effects of climate change. As climate change expedites poverty, Americans begin to blame others, such as queer people, for the destruction of their country. Butler depicts the dangers of fundamentalism as a response to climate change, highlighting an imperative for a movement that does not romanticize the environment as heteronormative, but …

Jewels For Dollars: Native And Nonnative Freshwater Fish Interactions In A Stressful Dry Down Environment, Vanessa Trujillo

FIU Electronic Theses and Dissertations

Vertebrate populations are subjected to novel anthropogenic stressors that are expected to multiply exponentially in the future. Introductions of nonnative species and human-altered hydrology are among these stressors to native species communities. The Rocky Glades, located in Everglades National Park, may serve as a population sink for native species that typically do not survive the altered hydrology of the dry season, and as a source of nonnative species that may be better adapted to chronically stressful conditions. In the seasonally-flooded Everglades, the nonnative African Jewelfish invaded in the 1960s and has since shown rapid range expansion. African Jewelfish are aggressive …

Green Sea Turtles (Chelonia Mydas) In Bermuda Exhibit An Ontogenetic Diet Shift Despite Overexploitation Of Resources In Their Developmental Habitat, Claire Margaret Burgett

FIU Electronic Theses and Dissertations

Green sea turtles in Bermuda are overgrazing the seagrasses on which later life stages are thought to specialize. I hypothesized that larger green turtles in Bermuda would display individual diet specializations during seagrass scarcity. Stable isotope methods were used to determine the diet composition of green sea turtles from the Bermuda Platform as a function of size class and in turtles captured in successive years. Individual turtles had a wide range of diets, however, the variation in diets was driven by differences among size class rather than within the size classes of larger turtles, indicating that green turtles undergo a …

Experimental Analysis Of The Effects Of Hydroscape Structure On Fishes In A Dynamic Wetland, Michael R. Bush

FIU Electronic Theses and Dissertations

Hydroscape structure can play a critical role in animal behavior, abundance, and community structure dynamics. Hydroscape configuration can be dynamic and can change quickly in ephemeral systems. However, ephemeral freshwater wetlands are among the most impacted systems in the world and restoration efforts often rely on incomplete information when establishing management objectives. Further understanding how alterations in hydroscape structure in dynamic systems affect animals is critical for conservation and management success.

To determine impacts that changing hydroscape conditions can have on consumers in freshwater wetlands, I examined the effects of a large-scale physical model on fish behavior, abundance, and community …

Examining Movement And Habitat Selection Of Everglades Fishes In Response To Seasonal Water Levels, Gregory J. Hill

FIU Electronic Theses and Dissertations

Fish distribution patterns and seasonal habitat use play a key role in the food web dynamics of aquatic ecosystems, including the Florida Everglades. In this study I examined the fine scale habitat shifts and movements of spotted sunfish, Lepomis punctatus across varying seasons and hydrologic conditions using in-situ field enclosures and Passive Integrated Transponder (PIT) systems. Data on fish use of three dominant Everglades marsh habitats and activity level were recorded continuously from January to August, 2015. Fish were more active and had the highest use of higher elevation habitats when water levels rose during an experimental reversal in mid-April. …

The Effects Of Artemisia Derived Natural Products On Adipogenesis, Steven Abood

FIU Electronic Theses and Dissertations

For the first time in human history, more people worldwide suffer from obesity than are undernourished. Numerous health complications are associated with obesity including cardiovascular disease, Type 2 Diabetes, cancers of reproductive tissues, stroke, depression, anxiety disorders, and Alzheimer’s disease. A deeper understanding of the anti-adipogenic effects and mechanism of action of sesquiterpene lactones may have pharmacological import in the continuing search for therapeutic modalities to ameliorate the effects of this global obesity epidemic.

Dehydroleucodine (DhL), 11,13-dihydro-dehydroleucodine (DH-DhL), and dehydroparashin-B (DhP), sesquiterpene lactones extracted from or derived from compounds extracted from Artemisia douglasiana, were investigated for their anti-adipogenic effects …

Effects Of Catastrophic Seagrass Loss And Predation Risk On The Ecological Structure And Resilience Of A Model Seagrass Ecosystem, Robert J. Nowicki

FIU Electronic Theses and Dissertations

As climate change continues, climactic extremes are predicted to become more frequent and intense, in some cases resulting in dramatic changes to ecosystems. The effects of climate change on ecosystems will be mediated, in part, by biotic interactions in those ecosystems. However, there is still considerable uncertainty about where and how such biotic interactions will be important in the context of ecosystem disturbance and climactic extremes.

Here, I review the role of consumers in seagrass ecosystems and investigate the ecological impacts of an extreme climactic event (marine heat wave) and subsequent widespread seagrass die-off in Shark Bay, Western Australia. Specifically, …

An Ecological Study Of The Anurans In Tea Plantations In A Biodiversity Hotspot, Lilly M. Eluvathingal

FIU Electronic Theses and Dissertations

Increasing human population size is increasing the demand for resources like timber, oil, tea, coffee, and other crops. Plantation crops mimic some aspects of native habitats, and there are studies that report the presence of some native anuran biodiversity in plantations. I focused on tea plantations in the Western Ghats-Sri Lanka Biodiversity Hotspot and studied the diversity and health of anurans in different habitats found within a tea cultivation area, near Munnar region in the Western Ghats, India. The landscape includes tea bushes, native evergreen shola forest patches, and eucalyptus forest stands. I reviewed 40 studies comparing amphibian species richness …

Screening Of Plants For Antibacterial Properties: Growth Inhibition Of Staphylococcus Aureus By Artemisia Tridentata, Steven Ross Eichelbaum

FIU Electronic Theses and Dissertations

Drug-resistant pathogenic and opportunistic bacteria are increasing in occurrence and prevalence, and pose a dangerous threat to human health. In the search for novel antibiotics with which to combat this threat, plants, specifically those used in traditional medicine with ascribed antibacterial properties, offer a promising and potentially vast source of such therapeutic compounds. The purpose of this study was therefore to screen chemical extracts created from various plant species for antibacterial properties versus pathogenic bacterial species. In the course of these antibacterial assays, we successfully identified a methanol extract derived from Artemisia tridentata tridentata plant material as capable of inhibiting …