Open Access. Powered by Scholars. Published by Universities.®

Ecology and Evolutionary Biology Commons™

Open Access. Powered by Scholars. Published by Universities.®

Theses and Dissertations

2018

Articles 1 - 22 of 22

Full-Text Articles in Ecology and Evolutionary Biology

River Bank Inducement Influence On A Shallow Groundwater Microbial Community And Its Effects On Aquifer Reactivity, Natalie June Gayner Dec 2018

River Bank Inducement Influence On A Shallow Groundwater Microbial Community And Its Effects On Aquifer Reactivity, Natalie June Gayner

Theses and Dissertations

Placing groundwater wells next to riverbanks to draw in surface water, known as riverbank inducement (RBI), is common and proposed as a promising and sustainable practice for municipal and public water production across the globe. However, these systems require further investigation to determine risks associated with river infiltration especially with rivers containing wastewater treatment plant (WWTP) effluent. Since microbes drive biogeochemical transformations in groundwater and largely affect water quality, it is important to understand how the microbial communities in drinking water wells are affected by river infiltration. This study investigated if, and to what extent, the microbial community in a …

Go to article

Cultivating Ecosystems: Microbial Communities In Recirculating Aquaculture Systems, Ryan Bartelme Aug 2018

Cultivating Ecosystems: Microbial Communities In Recirculating Aquaculture Systems, Ryan Bartelme

Theses and Dissertations

Intensive cultivation of fish is necessary to meet future global market demands. Recirculating aquaculture systems (RAS) enable dense growth of fish, while occupying less space than traditional aquaculture farms. However, RAS often experience complications and high fish mortalities due to disease and improper waste management. In properly functioning systems, the microorganisms associated with fish (gut, scales) as well as those found in the system environment (water, component surfaces) remove waste and maintain fish health by discouraging growth of opportunistic pathogens. Previous RAS microbiome studies are small in scope, utilize coarse methods, and contain limited long-term spatial or temporal data. With …

Go to article

Effects Of Life History And Brain Size On Cognition And Behavior: Studies On Prey-Searching In The Spider Pholcus Phalangioides, Joseph Kilmer Aug 2018

Effects Of Life History And Brain Size On Cognition And Behavior: Studies On Prey-Searching In The Spider Pholcus Phalangioides, Joseph Kilmer

Theses and Dissertations

There is tremendous diversity in body size across animals, including many examples of derived miniaturization. A reduction in body size is accompanied by a reduction in brain size, which is predicted to lead to limitations in cognition, but we have yet to find empirical evidence indicating what these limitations might be. I used a behavioral assay common in web spiders to explore this topic. I observed spiders as they searched for prey that they recently captured and lost. This assay has the advantage of being easily quantifiable while reflecting a spider’s evaluation and memory of lost prey. I conducted a …

Go to article

Chamaecrista Fasciculata In Tallgrass And Sand Prairies: The Potential For Differential Responses, Robert W. Philips Jun 2018

Chamaecrista Fasciculata In Tallgrass And Sand Prairies: The Potential For Differential Responses, Robert W. Philips

Theses and Dissertations

Successful establishment of a diversity of native species has become an important goal for restoration site managers to achieve, however as seed sources for a species may occur in habitats with different abiotic and biotic characteristics. Consequently, seeds from different sources may vary in their success in a restoration. Chamaecrista fasciculata, a native prairie species, occurs in two divergent prairie types - tallgrass and sand prairies. Tallgrass prairies have a moist soil with dense vegetation; in contrast, sand prairies have a well-drained sandy soil with sparse vegetation. I propose differential selection acting on populations in these prairie types would affect …

Go to article

When Does Less Equal More? Assessing The Mechanisms Driving Compensatory Mortality And The Hydra Effect, Joseph T. Neale Jun 2018

When Does Less Equal More? Assessing The Mechanisms Driving Compensatory Mortality And The Hydra Effect, Joseph T. Neale

Theses and Dissertations

Many populations across taxa are regulated by negative density-dependence, wherein increased population sizes lead to decreased birth rates and/or increased mortality. By releasing such populations from some level of these density-dependent effects, extrinsic mortality can lead to counter-intuitive results, such as no change in population size (compensation), or an increase in population size (overcompensation). These results have been documented experimentally, but there currently exists a dearth of empirical studies exploring the mechanisms behind the phenomenon. We tested the relationship between extrinsic mortality level and (over)compensation in four mosquito species – Aedes aegypti, A. albopictus, A. triseriatus, and Culex pipiens – …

Go to article

Sources Of Variation In Social Plasticity In Female Mate Preferences And Male Traits, Daniel Neelon May 2018

Sources Of Variation In Social Plasticity In Female Mate Preferences And Male Traits, Daniel Neelon

Theses and Dissertations

Female preferences are an important cause of selection on male traits, and exploring the sources of variation in these preferences has been the focus of intense behavioral research. This is due to the fact that understanding this variation is integral to understating the maintenance of variation and complexity in male traits, as well as the evolution and divergence of populations. This project aims to explore the sources of variation in these mating preferences, as well as examine whether similar sources affect components of male traits. This was accomplished using the well-studied mating system of the Green Treefrog, Hyla cinerea that …

Go to article

Invertebrate Paleoecology Of High Paleo-Latitude Carboniferous Strata Of The Tepuel-Genoa Basin, Argentina, Kate M. Gigstad May 2018

Invertebrate Paleoecology Of High Paleo-Latitude Carboniferous Strata Of The Tepuel-Genoa Basin, Argentina, Kate M. Gigstad

Theses and Dissertations

The Late Paleozoic Ice Age (LPIA), which began in the latest Devonian and ended in the Late Permian, was a time of active environmental changes. During this time, glaciers waxed and waned over the ancient continent of Gondwana that was situated over the southern pole. This time of transition from icehouse to greenhouse in the Permian is our closest analogue to our current environmental conditions and increased knowledge of our planetary past will greatly influence our future. Much of the previous research on marine invertebrate paleoecology during the LPIA occurs in far-field or low paleolatitude localities, but less is known …

Go to article

Assessment And Mapping Of The Milwaukee Estuary Habitat, Brennan Dow May 2018

Assessment And Mapping Of The Milwaukee Estuary Habitat, Brennan Dow

Theses and Dissertations

Rivermouth regions such as the Milwaukee Harbor, are the habitat interface between watersheds and the Great Lakes proper, and can host a large diversity of fishes. To facilitate an ecosystem approach management strategy, I developed a layered map that includes bathymetry, side scan sonar images, shoreline substrate classifications, and initial data of aquatic vegetation and centrarchid spawning locations. The 60 km perimeter of the study area consisted of 59% hardened shoreline. Ground truthing of substrate classifications via Ponar grabs or video had about 95% accuracy for fine and rocky boulder substrates. Rocky fine was the most inaccurate classification (35%), but …

Go to article

Influence Of Natural And Anthropogenic Light Levels On Female Preferences In Eastern Gray Treefrogs (Hyla Versicolor), Victoria Underhill May 2018

Influence Of Natural And Anthropogenic Light Levels On Female Preferences In Eastern Gray Treefrogs (Hyla Versicolor), Victoria Underhill

Theses and Dissertations

Chapter 1: While the influence of environmental variables, particularly temperature and rainfall, on the breeding behavior of amphibians is widely recognized, relatively few studies have addressed how the moon affects amphibian behavior. Yet, the lunar cycle provides several rhythmic temporal cues that animals could use to time important group events such as spawning, and the substantial changes in light levels associated with the different moon phases may also affect the behavior of nocturnal frogs. Using seven years of field observation data, we tested for lunar effects on the reproductive activity of male and female Eastern gray treefrogs (Hyla versicolor). We …

Go to article

Learning To See The Forest For The Corn: Establishing Sense Of Place And Community In A Field-Based Ecology Course For Pre-Service Educators, Michelle Edgcomb Friday Feb 2018

Learning To See The Forest For The Corn: Establishing Sense Of Place And Community In A Field-Based Ecology Course For Pre-Service Educators, Michelle Edgcomb Friday

Theses and Dissertations

In this dissertation grounded theory techniques were used to characterize pre-service educators’ experiences in a semester-long, field-based ecology course. Through participation in a citizen science project, participants formed a community of practice that extended their conceptions of themselves as ecology students and scientists. Extended field experiences in a variety of local ecosystems contributed to the development of a sense of place. Paired fieldwork with lecture aided their developing ecological literacy and their understanding of place-based pedagogy. All of these combined to support their growing understanding of their role in field-based ecology education. Lack of background in ecology and ecology pedagogy …

Go to article

How The Egg Rolls: A Morphological Analysis Of Egg Shape In The Context Of Displacement Dynamics, Ian R. Hays Jan 2018

How The Egg Rolls: A Morphological Analysis Of Egg Shape In The Context Of Displacement Dynamics, Ian R. Hays

Theses and Dissertations

Very little is known about how morphology effects the motion, stability and the resulting viability of avian eggs. The limited research that exists focuses on the pyriform or ‘pointed’ egg shapes found in the Alcidea family. This unusual shell form is thought to suppress displacement and prevents egg loss on the cliffside nesting habitat of the Uria genera. Unfortunately, these studies never isolated or quantify the specific morphological features (elongation, asymmetry and conicality) of these pyriform eggs, which limits their applicability to other taxa and hampers a robust proof of concept. We isolated each feature as a variable, produced models …

Go to article

The Role Of Vegetation-Topographic Interactions In A Barrier Island System: Island Migration In A Changing Climate, Benjamin Nettleton Jan 2018

The Role Of Vegetation-Topographic Interactions In A Barrier Island System: Island Migration In A Changing Climate, Benjamin Nettleton

Theses and Dissertations

Islands have been characterized based on vegetation and topography as exhibiting different disturbance regimes - reinforcing or resisting. This study had two objectives: quantify barrier island upland migration and vegetation cover change over 32 years (1984-2016), and assess tolerance of two prevalent dune grass species, A. breviligulata, and S. patens to sand burial. Using Landsat imagery from the Virginia Coast Reserve, islands were categorized within the disturbance resistance/reinforcing framework based on dune elevation. Resistant areas were associated with woody cover and low marsh to upland migration while reinforcing areas had low vegetation cover and high rates of migration. System-wide, …

Go to article

Natural And Anthropogenic Drivers Of Tree Evolutionary Dynamics, Brandon M. Lind Jan 2018

Natural And Anthropogenic Drivers Of Tree Evolutionary Dynamics, Brandon M. Lind

Theses and Dissertations

Species of trees inhabit diverse and heterogeneous environments, and often play important ecological roles in such communities. As a result of their vast ecological breadth, trees have become adapted to various environmental pressures. In this dissertation I examine various environmental factors that drive evolutionary dynamics in threePinusspecies in California and Nevada, USA. In chapter two, I assess the role of management influence of thinning, fire, and their interaction on fine-scale gene flow within fire-suppressed populations of Pinus lambertiana, a historically dominant and ecologically important member of mixed-conifer forests of the Sierra Nevada, California. Here, I find evidence …

Go to article

Forest Structural Complexity And Net Primary Production Resilience Across A Gradient Of Disturbance In A Great Lakes Ecosystem, Lisa T. Haber Jan 2018

Forest Structural Complexity And Net Primary Production Resilience Across A Gradient Of Disturbance In A Great Lakes Ecosystem, Lisa T. Haber

Theses and Dissertations

Forests are an important component of the global carbon (C) cycle and contribute to climate change mitigation through atmospheric C uptake and storage in biomass and soils. However, the forest C sink is susceptible to disturbance, which modifies physical and biological structure and limits spatial extent of forests. Unlike severe, stand-replacing disturbances that reset forest successional trajectories and may simplify ecosystem structure, moderate severity disturbances may instead introduce complexity in ways that sustain net primary production (NPP), leading to the phenomenon of “NPP resilience.” In this study, we examined the linkage between disturbance severity and ecosystem biological and physical structural …

Go to article

Floral Symmetry Genes Elucidate The Development And Evolution Of Oil-Bee Pollinated Flowers Of Malpighiaceae And Krameriaceae, Farahnoz N. Khojayori Jan 2018

Floral Symmetry Genes Elucidate The Development And Evolution Of Oil-Bee Pollinated Flowers Of Malpighiaceae And Krameriaceae, Farahnoz N. Khojayori

Theses and Dissertations

Specialization on insect and animal pollinators is thought to be the driving force for the evolution of floral traits. Specifically in the New World (NW), the oil-bee pollination syndrome has led to the convergence of floral characters in two distantly related families of core eudicots, Malpighiaceae and Krameriaceae. Both families display a flag-like structure that establishes a zygomorphic flower and floral oil rewards in epithelial elaiophores. These traits work concomitantly to attract and reward female oil-bees that help fertilize these flowers and in return receive oils. The underlying genetics of floral zygomorphy were studied in several clades of core eudicots, …

Go to article

Climate Change And Mountaintop Removal Mining: A Maxent Assessment Of The Potential Dual Threat To West Virginia Fishes, Lindsey R F Hendrick Jan 2018

Climate Change And Mountaintop Removal Mining: A Maxent Assessment Of The Potential Dual Threat To West Virginia Fishes, Lindsey R F Hendrick

Theses and Dissertations

Accounts of species’ range shifts in response to climate change, most often as latitudinal shifts towards the poles or upslope shifts to higher elevations, are rapidly accumulating. These range shifts are often attributed to species ‘tracking’ their thermal niches as temperatures in their native ranges increase. Our objective was to estimate the degree to which climate change-driven shifts in water temperature may increase the exposure of West Virginia’s native freshwater fishes to mountaintop removal surface coal mining. Mid-century shifts in habitat suitability for nine non-game West Virginia fishes were projected via Maximum Entropy species distribution modeling, using a combination of …

Go to article

Evolving Reproductive Isolation In The Parasitic Wasp Genus Cotesia, Justin P. Bredlau Jan 2018

Evolving Reproductive Isolation In The Parasitic Wasp Genus Cotesia, Justin P. Bredlau

Theses and Dissertations

Parasitic wasps are highly diverse and play a major role in suppression of herbivorous pest populations, but relatively little is known of the mechanisms driving their diversity. Molecular studies indicate that cryptic species complexes resulting from adaptations to specific hosts or host-foodplants may be common. The gregarious endoparasitoid, Cotesia congregata (Braconidae), is a model system for understanding parasitic wasp biology. It is reported to attack at least 15 species of sphingid caterpillars, most of which are plant family specialists. Molecular studies have demonstrated genetic differentiation of two host-foodplant complex sources originating from Manduca sexta on tobacco (MsT) and Ceratomia catalpae …

Go to article

Red-Headed Woodpecker Full Annual Cycle Ecology At Fort A.P. Hill, Virginia, Benjamin Nickley Jan 2018

Red-Headed Woodpecker Full Annual Cycle Ecology At Fort A.P. Hill, Virginia, Benjamin Nickley

Theses and Dissertations

The red-headed woodpecker is a primary cavity excavator found throughout the Eastern Deciduous Forest and parts of the Great Plains. Although widespread, the red-headed woodpecker is generally considered uncommon, with patchily distributed populations. Over the past 50 years, this species has experienced precipitous, range-wide declines. The red-headed woodpecker uses a variety of cover types to meet resource needs across the annual cycle, ranging from oak savannas and wetlands, to mature beech forests and urban parks. Given their apparent adaptability to such a wide range of habitats, causes of declines are perplexing. To understand and stem declines, recent studies have focused …

Go to article

Identification Of Taxonomic And Functional Ichthyofaunal Zones Within The James River Basin, Virginia, Joseph L. Noel Jan 2018

Identification Of Taxonomic And Functional Ichthyofaunal Zones Within The James River Basin, Virginia, Joseph L. Noel

Theses and Dissertations

Environmental gradients structure ichthyofaunal communities longitudinally along river networks via the selective filtering of species’ traits. In many instances, these environmental influences have created distinct zones of co-occurring fish species. Zonation studies have most often been conducted with taxonomic data (species x site matrices), but the increasing availability of functional trait data creates an opportunity to build more rigorous understanding of species’ co-occurrence patterns. Notably, zonation studies that use taxonomic data may not reveal the same patterns as studies based on trait data. In this study, we tested for distinct ichthyofaunal zonation in James River Basin, VA using a combination …

Go to article

Migratory Patterns And Population Genetic Structure In A Declining Wetland-Dependent Songbird, Matthew G. Desaix Jan 2018

Migratory Patterns And Population Genetic Structure In A Declining Wetland-Dependent Songbird, Matthew G. Desaix

Theses and Dissertations

Understanding migratory connectivity is essential for assessing the drivers behind population dynamics and for implementing effective management in migratory species. Genetic markers provide a means to describe migratory connectivity, as well as incorporate population genetic analyses, however genetic markers can be uninformative for species with weak genetic structure. In this study, we evaluate range-wide population genetic structure and migratory connectivity in the prothonotary warbler, Protonotaria citrea, a wetland-dependent neotropical migratory songbird, using high-resolution genetic markers. We reveal regional genetic structure between sampling sites in the Mississippi River Valley and the Atlantic Seaboard with overall weak genetic differentiation among populations …

Go to article

Using Maximum Entropy To Model The Distribution Of An Endangered, Endemic Crayfish Cambarus Harti (Hobbs), James Kiourtsis Jan 2018

Using Maximum Entropy To Model The Distribution Of An Endangered, Endemic Crayfish Cambarus Harti (Hobbs), James Kiourtsis

Theses and Dissertations

Cambarus harti is a state-listed endangered, endemic crayfish found only in three counties in mid-west Georgia. Several studies have attempted to characterize the biology and ecology of this crayfish, however data regarding the distribution of this rare, endemic crayfish remains limited. The International Union for Conservation of nature stated that in order to create an effective conservation plan, the known distribution must be expanded. Species distribution models are a cost-effective way to identify locations that have similar habitat characteristics to those with known populations. One species distribution model, Maximum Entropy (MaxEnt), is the preferred approach when modeling species, like C. …

Go to article

Improving Estuarine Water Quality In South Florida: A Quantitative Evaluation Of The Efficacy Of A Local Nutrient Ordinance, Kerstin Motsch Jan 2018

Improving Estuarine Water Quality In South Florida: A Quantitative Evaluation Of The Efficacy Of A Local Nutrient Ordinance, Kerstin Motsch

Theses and Dissertations

Degraded coastal water quality is a concern in Florida, in part due to nutrient enrichment of aquatic ecosystems causing eutrophication and excessive algal growth. In 2010, a fertilizer ordinance was enacted in Cape Coral located in Lee County Florida with the objective of reducing nutrient loads from local fertilizing practices in order to improve water quality within the city. In order to assess its efficacy, a before after control impact (BACI) design was implemented using Fort Lauderdale in Broward County Florida as a reference location. A total of twenty estuarine canal sampling locations were identified in both Lee and Broward …

Go to article