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Evaluating Potential For Water Quality Decline In Maine Lakes, Kaci N. Fitzgibbon Dec 2017

Evaluating Potential For Water Quality Decline In Maine Lakes, Kaci N. Fitzgibbon

Electronic Theses and Dissertations

Understanding lake vulnerability with respect to eutrophication and loss of water quality is important for sustainability of aquatic ecosystems. This project aims at identifying and quantifying the effects of relevant physiochemical, climate, and watershed characteristics on lake vulnerability in order to develop management decision tools for the Maine Department of Environmental Protection (MEDEP). In a changing chemical and physical environment, using independent variables from each of these categories and then relating them to the summer lake epilimnetic phosphorus (P) concentrations allows for development of models to inform stakeholders of lake vulnerability to eutrophication problems.

We studied 24 lakes covering a …


Water Chemistry Dynamics In Four Vernal Pools In Maine, Usa, Lydia H. Kifner Dec 2017

Water Chemistry Dynamics In Four Vernal Pools In Maine, Usa, Lydia H. Kifner

Electronic Theses and Dissertations

Vernal pools are small seasonal wetlands that are a common landscape feature that contribute to biodiversity in northeastern North American forests. However, even basic information about their biogeochemical functions, such as carbon cycling, is limited. Dissolved gas concentrations (CH4, CO2) and other water chemistry parameters were monitored weekly at the bottom and surface of four vernal pools in central and eastern Maine, USA, from April to August 2016. The vernal pools were supersaturated with respect to CH4 and CO2 at all sampling dates and locations. Concentrations of dissolved CH4 and CO2 ranged …


Only The Earth Remains: Exploring The Machine In Selected Lyric Poetry Of Robinson Jeffers, Mark Hutton Dec 2017

Only The Earth Remains: Exploring The Machine In Selected Lyric Poetry Of Robinson Jeffers, Mark Hutton

Electronic Theses and Dissertations

In The Machine in the Garden: Technology and the Pastoral Idea in America, Leo Marx “evaluates the uses of the pastoral ideal in the interpretation of American experience” (Marx 4). While Marx explores ways that pastoralism has been impacted by factors such as industrialism, it is the purpose of this project to explore Marx’s assertion regarding the presence of the figurative and literal machine within the poetry of Robinson Jeffers.

Jeffers’ poetry is generally located within the landscapes of California. His lyric poetry has a distinct connection to the land and is driven by inhumanism, which works to shift …


Greater London In The 21st Century : Assessing Coastal Flooding Mitigation Preparedness And Regional Population Risk In The Face Of Projected Sea-Level Rise., Nathan K Wright Dec 2017

Greater London In The 21st Century : Assessing Coastal Flooding Mitigation Preparedness And Regional Population Risk In The Face Of Projected Sea-Level Rise., Nathan K Wright

Electronic Theses and Dissertations

Recent projections of +6-9m sea-level rise (SLR) over the next several decades present many social challenges for coastal regions during the 21st century. These projections were applied to Greater London, UK as areal interpolated historical census data was overlaid on a 50m DEM alongside a polyline projection of the Thames Barrier. Population was projected to milestones of 2041, 2071, and 2101 using a capped, aggregated growth rate for each polygon while SLR was simulated for 1m, 5m, and 9m scenarios. The Thames Barrier maintained integrity for 1m and 5m scenarios but was breached at 9m. Population continued to increase …


Geophysical Delineation Of Megaporosity And Fluid Migration Pathways For Geohazard Characterization Within The Delaware Basin, Culberson County, Texas, Jonathan David Woodard Dec 2017

Geophysical Delineation Of Megaporosity And Fluid Migration Pathways For Geohazard Characterization Within The Delaware Basin, Culberson County, Texas, Jonathan David Woodard

Electronic Theses and Dissertations

ABSTRACT

Differential dissolution of gypsum karst within the Delaware Basin poses a significant threat to infrastructure that society depends on. The study area is located in Culberson County, Texas and traverses a distance of approximately 54 kilometers along RM 652 within the Gypsum Plain which is situated on the northern margin of the Chihuahua Desert and includes outcrops of Castile and Rustler strata that host karst geohazards. Regions of karst geohazard potential have been physically surveyed proximal to the study area in evaporites throughout the Castile Formation outcrop; minimal hazards, in comparison to the Castile Formation, have been documented in …


Spatially Explicit Model Of Areas Between Suitable Black Bear Habitat In East Texas And Black Bear Populations In Louisiana, Arkansas, And Oklahoma, Caitlin M. Glymph, Christopher Comer, Daniel Scognamillo, Daniel Unger, Yanli Zhang Nov 2017

Spatially Explicit Model Of Areas Between Suitable Black Bear Habitat In East Texas And Black Bear Populations In Louisiana, Arkansas, And Oklahoma, Caitlin M. Glymph, Christopher Comer, Daniel Scognamillo, Daniel Unger, Yanli Zhang

Electronic Theses and Dissertations

Although black bears (Ursus americanus, Ursus americanus luteolus) were once found throughout the south-central United States, unregulated harvest and habitat loss resulted in severe range retractions and by the beginning of the twentieth century populations in Oklahoma, Louisiana, Texas and Arkansas were nearing extirpation. In response to these losses, translocation programs were initiated in Arkansas (1958-1968 & 2000-2006) and Louisiana (1964-1967 & 2001-2009). These programs successfully restored bears to portions of Louisiana and Arkansas, and, as populations in Arkansas began dispersing, to Oklahoma. In contrast, east Texas remains unoccupied despite the existence of suitable habitat in the region.

To facilitate …


Using Hydroacoustics To Investigate Biological Responses In Fish Abundance To Restoration Efforts In The Penobscot River, Maine, Constantin C. Scherelis Aug 2017

Using Hydroacoustics To Investigate Biological Responses In Fish Abundance To Restoration Efforts In The Penobscot River, Maine, Constantin C. Scherelis

Electronic Theses and Dissertations

Spatiotemporal advantages linked to hydroacoustic sampling techniques have caused a surge in the use of these techniques for fisheries monitoring studies applied over long periods of time in marine systems. Dynamic physical conditions such as tidal height, boat traffic, floating debris, and suspended particle concentrations result in unwanted noise signatures that vary in intensity and location within a hydroacoustic beam over time and can be mixed with the acoustic returns from intended targets (e.g., fish). Typical processing filters applied over long term datasets to minimize noise and maximize signals do not address spatiotemporal fluctuations of noise in dynamic systems. We …


Window Inserts And The People Adopting Them: Building Sustainable Communities In Maine, Daniel Sean Mistro Aug 2017

Window Inserts And The People Adopting Them: Building Sustainable Communities In Maine, Daniel Sean Mistro

Electronic Theses and Dissertations

Residents of Maine face a large monetary expense to heat their homes in the winter. In Maine it takes 540 gallons of heating oil each year to heat a typical home [1]. Interior window inserts may be a practical solution to improve comfort, save money, and consume less environmentally harmful fossil fuels during cold winter months. The window inserts discussed in this paper are custom measured to fit into a window and consist of a wooden frame that is wrapped in two layers of polyolefin film and weather stripped for a snug fit. Commercial inserts cost $20-$36/square foot, or approximately …


Ecological Informatics: An Agent Based Model On Coexistence Dynamics, Shiva Thapa Aug 2017

Ecological Informatics: An Agent Based Model On Coexistence Dynamics, Shiva Thapa

Electronic Theses and Dissertations

The coexistence of species is probably one of the most interesting and complex phenomenon in nature. We constructed an agent based model to study the coexistence dynamics of prey - predator populations by varying productivity levels of producers in fragmented and connected habitats along with different levels of quality of predators. Our results indicated that productivity levels of producers in fragmented and connected habitats along with levels of predator quality are significantly responsible for overall predator - prey population size and survivorship. In the absence of predation, competition between identical prey populations is more probable in connected habitats than in …


Sea Lamprey (Petromyzon Marinus) As A Functional Link Between Marine And Freshwater Ecosystems, Daniel M. Weaver Aug 2017

Sea Lamprey (Petromyzon Marinus) As A Functional Link Between Marine And Freshwater Ecosystems, Daniel M. Weaver

Electronic Theses and Dissertations

Anadromous sea lamprey Petromyzon marinus are native to Atlantic coastal systems and serve as a functional link between marine and freshwater ecosystems. Sea lamprey spend 1–2 years in the ocean parasitizing marine vertebrates before migrating into freshwaters during the spring to spawn. There they construct nests, spawn, then die shortly afterwards. Larvae hatch, bury into fine sediments and reside in streams for generally 6–8 years, but up to 14. Larvae then undergo metamorphosis, a non-feeding period characterized by a series of physical and physiological changes. The juveniles (macropthalmia) then migrate to the ocean to begin the parasitic juvenile phase.

Historically, …


Survival, Harvest, And Drumming Ecology Of Ruffed Grouse In Central Maine, Usa, Samantha Davis Aug 2017

Survival, Harvest, And Drumming Ecology Of Ruffed Grouse In Central Maine, Usa, Samantha Davis

Electronic Theses and Dissertations

Understanding population dynamics and how species interact with their environment are important components for conservation and management. Ruffed grouse (Bonasa umbellus) are a widely distributed and common game bird in North America and are a considered an important economic and cultural icon in Maine. Although they are a well-studied species, there has been little research focused on ruffed grouse population dynamics and habitat relationships in Maine. My thesis aims to improve this knowledge gap by focusing on research related to survival and harvest of ruffed grouse, as well as male ruffed grouse resource selection at breeding display sites. Ruffed grouse …


Vulnerability Assessment Of Groundwater To No3 Contamination Using Gis, Drastic Model And Geostatistical Analysis, Adela Beauty Adu Agyemang Aug 2017

Vulnerability Assessment Of Groundwater To No3 Contamination Using Gis, Drastic Model And Geostatistical Analysis, Adela Beauty Adu Agyemang

Electronic Theses and Dissertations

The study employed Geographical Information System (GIS) technology to investigate the vulnerability of groundwater to NO3 content in Buncombe County, North Carolina in two different approaches. In the first study, the spatial distribution of NO3 contamination was analyzed in a GIS environment using Kriging Interpolation. Cokriging interpolation was used to establish how NO3 relates to land cover types and depth to water table of wells in the county. The second study used DRASTIC model to assess the vulnerability of groundwater in Buncombe County to NO3 contamination. To get an accurate vulnerability index, the DRASTIC parameters were …


Effects Of Ponderosa Pine Ecological Restoration On Forest Soils And Understory Vegetation In Northern Arizona, Elena M. Thomas, Kenneth W. Farrish, Brian P. Oswald, Melinda G. Shaw-Faulkner, Scott R. Abella May 2017

Effects Of Ponderosa Pine Ecological Restoration On Forest Soils And Understory Vegetation In Northern Arizona, Elena M. Thomas, Kenneth W. Farrish, Brian P. Oswald, Melinda G. Shaw-Faulkner, Scott R. Abella

Electronic Theses and Dissertations

The human exclusion of wildfire and overgrazing by livestock since settlement have caused dramatic changes in ponderosa pine (Pinus ponderosa Dougl ex Laws) forest ecosystems. These changes include increased numbers of tree stems, reduced understory cover and diversity, and the introduction of invasive, non-native understory species. This study evaluated the coverage and species composition of understory vegetation present in the “cool-season” (late spring and early summer) in a ponderosa pine forest on grazed and ungrazed plots that had undergone restoration treatments on three different soil/geologic parent material types near Flagstaff, Arizona, twelve years after tree thinning and grazing exclosure …


Assessment And Characterization Of Microbial Communities In Salt Affected Soils On Galveston Island, Elaine Fowler May 2017

Assessment And Characterization Of Microbial Communities In Salt Affected Soils On Galveston Island, Elaine Fowler

Electronic Theses and Dissertations

After Hurricane Ike in 2008, Galveston Island was flooded with sea water that left the soil and groundwater of the island with elevated sodium concentrations. As part of a long-term study that aims to restore plant life to the island, various soil amelioration techniques are being evaluated. Samples from bedded and non- bedded plots treated with gypsum, mulch, or both were assessed for microbial populations. Samples collected in July and October 2016 were cultured on Tryptic Soy Agar (bacteria enumeration), Pseudomonas Agar, Actinomycete Agar, and Rose Bengal Agar (fungi enumeration). Bacteria populations ranged from 4.07 to 5.12 log CFU/gram and …


Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett May 2017

Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett

Electronic Theses and Dissertations

Lilium grayi (Gray’s Lily), a southern Appalachian endemic species, is threatened by a Lilium-specific fungal pathogen, Pseudocercosporella inconspicua. The disease is characterized by tan lesions that can cause early senescence, while also lowering seed production and viability. This project tested for P. inconspicua conidia and accessed health at nine locations. The disease was present and ubiquitous across the range of L. grayi. Through identification of P. inconspicua conidia in the field, L. superbum (Turk’s Cap Lily) was identified as an additional host, while L. michauxii (Michaux’s Lily) was disease-free. However, infection was inducible in both species. With …


Spatiotemporal Analyses Of Recycled Water Production, Jana E. Archer May 2017

Spatiotemporal Analyses Of Recycled Water Production, Jana E. Archer

Electronic Theses and Dissertations

Increased demands on water supplies caused by population expansion, saltwater intrusion, and drought have led to water shortages which may be addressed by use of recycled water as recycled water products. Study I investigated recycled water production in Florida and California during 2009 to detect gaps in distribution and identify areas for expansion. Gaps were detected along the panhandle and Miami, Florida, as well as the northern and southwestern regions in California. Study II examined gaps in distribution, identified temporal change, and located areas for expansion for Florida in 2009 and 2015. Production increased in the northern and southern regions …


Remotely Sensed Heat : Variation And Change In Surface Urban Heat Islands In A Temperate Eco-Region Of The United States., Jeremy Sandifer May 2017

Remotely Sensed Heat : Variation And Change In Surface Urban Heat Islands In A Temperate Eco-Region Of The United States., Jeremy Sandifer

Electronic Theses and Dissertations

Urban heat island (UHI) is a term used to describe increased surface and atmospheric temperatures in an urban core relative to surrounding non-urbanized areas. To examine the variability introduced into derived estimates of the surface UHI, this study constructs and compares multiple remotely sensed indicators of the surface UHI for major metropolitan cities of a temperate eco-region of the United States. The Moderate Resolution Imaging Spectroradiometer (MODIS) 8-day, 500-meter product (MOD11A2) is the source data used to calculate six different RS-derived UHI indicators for the year 2002 to 2012. The different SUHI indicators are evaluated using the Spearmans Rho rank-order …


An Analysis Of The Relationship Between Snowpack And Groundwater Across Utah Watersheds., Samuel Wright May 2017

An Analysis Of The Relationship Between Snowpack And Groundwater Across Utah Watersheds., Samuel Wright

Electronic Theses and Dissertations

This thesis examined what type of relationship existed between snow water equivalence (SWE) volume and groundwater elevation within six sub-watersheds in Utah. Data was gathered on SWE from seventeen SNOTEL sites and groundwater elevation data was gathered from six continuously monitored groundwater wells. This data was gathered for January through May for 2011, 2013, and 2014 in order to represent the water conditions that were above average, below average, and average respectively. Using MLR formulas the total SWE for each sub-watershed was determined for each year/month. Afterwards a correlation analysis was performed to determine if any association existed between SWE …


Black Bears (Ursus Americanus) Versus Brown Bears (U. Arctos): Combining Morphometrics And Niche Modeling To Differentiate Species And Predict Distributions Through Time, Theron Michael Kantelis May 2017

Black Bears (Ursus Americanus) Versus Brown Bears (U. Arctos): Combining Morphometrics And Niche Modeling To Differentiate Species And Predict Distributions Through Time, Theron Michael Kantelis

Electronic Theses and Dissertations

Late Pleistocene American black bears (Ursus americanus) often overlap in size with Pleistocene brown bears (U. arctos), occasionally making them difficult to diagnose. Large U. americanus have previously been distinguished from U. arctos by the length of the upper second molar (M2). However, the teeth of fossil U. americanus sometimes overlap size with U. arctos. As such, there is need for a more accurate tool to distinguish the two species. Here, 2D geometric morphometrics is applied to the occlusal surface of the M2 to further assess the utility of this tooth for distinguishing U. americanus and …


The Tuscaloosa Marine Shale: Geologic History, Depositional Analysis, And Exploration Potential, Jessica D. Pair Feb 2017

The Tuscaloosa Marine Shale: Geologic History, Depositional Analysis, And Exploration Potential, Jessica D. Pair

Electronic Theses and Dissertations

The Tuscaloosa Marine Shale (TMS) was deposited across southern Louisiana and Mississippi during the Upper Cretaceous. The study focuses on a core region containing vast deposits of Cretaceous-aged sediments that have economic importance for oil and gas exploration. This region has been conventionally drilled for decades, focusing on the recovery of the Cretaceous hydrocarbons. Explorers within this region had traditionally targeted the massive sand units of the Lower and Upper Tuscaloosa Group while neglecting the middle Tuscaloosa Marine Shale unit. With the onset of unconventional drilling technology, new explorers to the region have begun to delineate the Tuscaloosa Marine Shale’s …


Ichetucknee Springs: Measuring The Effects Of Visitors On Water Quality Parameters Through Continuous Monitoring., Sarah Faraji Jan 2017

Ichetucknee Springs: Measuring The Effects Of Visitors On Water Quality Parameters Through Continuous Monitoring., Sarah Faraji

Electronic Theses and Dissertations

Ichetucknee Springs System is in north central Florida, under the jurisdiction of the Suwannee River Water Management District (SRWMD). The Ichetucknee River is one of the most pristine spring-fed rivers in Florida and became a state park in 1970. Over 400,000 people visited the Ichetucknee Springs State Park in 2016. From that total, over 130,000 people came during the tubing season alone (Memorial Day to Labor Day). During the tubing season, only 750 visitors per day are allowed to launch from the North Launch, near the Ichetucknee Head Spring. The park enforces visitor usage of the river during these time …


Groundwater Modeling For Assessing The Impacts Of Natural Hazards In East-Central Florida, Han Xiao Jan 2017

Groundwater Modeling For Assessing The Impacts Of Natural Hazards In East-Central Florida, Han Xiao

Electronic Theses and Dissertations

In coastal east-central Florida (ECF) , the low-lying coastal alluvial plains and barrier islands have a high risk of being inundated by seawater due to climate change effects such as sea-level rise, changing rainfall patterns, and intensified storm surge from hurricanes., This will produce saltwater intrusion into the coastal aquifer from infiltration of overtopping saltwater. In the inland ECF region, sinkhole occurrence is recognized as the primary geologic hazard causing massive financial losses to society in the past several decades. The objectives of this dissertation are to: (1) evaluate the impacts of sea-level rise and intensified storm surge on the …


Assessing Interactions Between Estuary Water Quality And Terrestrial Land Cover In Hurricane Events With Multi-Sensor Remote Sensing, Chandan Mostafiz Jan 2017

Assessing Interactions Between Estuary Water Quality And Terrestrial Land Cover In Hurricane Events With Multi-Sensor Remote Sensing, Chandan Mostafiz

Electronic Theses and Dissertations

Estuaries are environmentally, ecologically and environmentally important places as they act as a meeting place for land, freshwater and marine ecosystems. They are also called nurseries of the sea as they often provide nesting and feeding habitats for many aquatic plants and animals. These estuaries also withstand the worst of some natural disasters, especially hurricanes. The estuaries as well as the harbored ecosystems undergo significant changes in terms of water quality, vegetation cover etc. and these components are interrelated. When hurricane makes landfall it is necessary to assess the damages as quickly as possible as restoration and recovery processes are …


Sources And Long-Term Trends In Fecal Bacteria Contamination In The Fresh And Marine Waters Of The Grand Strand, Cara E. Schildtknecht Jan 2017

Sources And Long-Term Trends In Fecal Bacteria Contamination In The Fresh And Marine Waters Of The Grand Strand, Cara E. Schildtknecht

Electronic Theses and Dissertations

Microbial water quality is of significant concern in the two watersheds of the Grand Stand. Polluted runoff, malfunctioning septic tanks, and centralized sanitary sewer failures are common sources of fecal bacteria contamination in coastal areas and pose a threat to human health through recreational use of waterbodies and shellfish consumption. Volunteer water quality monitoring programs are crucial in expanding upon assessments of fecal bacteria contamination by regulatory monitoring. Bacteria monitoring data collected by volunteers and Coastal Carolina University’s Environmental Quality Laboratory has been used to identify sites to be investigated by microbial source tracking. Microbial source tracking has been used …


Land Surface Phenologies And Seasonalities Using Cool Earthlight In Temperate And Tropical Croplands, Woubet Gashaw Alemu Jan 2017

Land Surface Phenologies And Seasonalities Using Cool Earthlight In Temperate And Tropical Croplands, Woubet Gashaw Alemu

Electronic Theses and Dissertations

In today’s world of increasing food insecurity due to more frequent and extreme events (droughts, floods), a comprehensive understanding of global cropland dynamics is critically needed. Land surface parameters derived from the passive microwave Advanced Microwave Scanning Radiometer on EOS (AMSR-E) and AMSR2 data enable monitoring of cropland dynamics and they can complement visible to near infrared (VNIR) and thermal infrared (TIR) data. Passive microwave data are less sensitive to atmospheric effects, cloud contamination, and solar illumination constraints resulting in finer temporal resolution suitable to track the temporal progression of cropland cover development compared to the VNIR data that has …


Evaluation Of The Deadwood Bighorn Sheep Herd Translocation, Ty J. Werdel Jan 2017

Evaluation Of The Deadwood Bighorn Sheep Herd Translocation, Ty J. Werdel

Electronic Theses and Dissertations

From 2015-2017, we evaluated a newly established bighorn sheep (Ovis canadensis) herd in the Deadwood Region of the Black Hills, South Dakota. Our objectives were to 1a) determine annual survival rates, 1b) determine cause-specific mortality, 1c) estimate population size, 2a) assess genetic diversity, 2b) assess disease prevalence, 3) evaluate movement patterns post-release, 4a) evaluate 3rd-order habitat selection, and 4b) estimate herbaceous biomass at foraging sites post-release of translocated bighorn sheep. In February 2015, we captured and translocated 26 bighorn sheep from the Luscar Mine near Hinton, Alberta, Canada to the Deadwood Region of the Black Hills, South Dakota. Overall annual …


Using Remote Sensing To Estimate Crop Water Use To Improve Irrigation Water Management, Arturo Reyes-Gonzalez Jan 2017

Using Remote Sensing To Estimate Crop Water Use To Improve Irrigation Water Management, Arturo Reyes-Gonzalez

Electronic Theses and Dissertations

Irrigation water is scarce. Hence, accurate estimation of crop water use is necessary for proper irrigation managements and water conservation. Satellite-based remote sensing is a tool that can estimate crop water use efficiently. Several models have been developed to estimate crop water requirement or actual evapotranspiration (ETa) using remote sensing. One of them is the Mapping EvapoTranspiration at High Resolution using Internalized Calibration (METRIC) model. This model has been compared with other methods for ET estimations including weighing lysimeters, pan evaporation, Bowen Ratio Energy Balance System (BREBS), Eddy Covariance (EC), and sap flow. However, comparison of METRIC model outputs to …


The Decline And Recovery Of Thermal Oxidative Stability Of Ultra-Low Sulfur Diesel Blends, Abigail Schoor Cohen Jan 2017

The Decline And Recovery Of Thermal Oxidative Stability Of Ultra-Low Sulfur Diesel Blends, Abigail Schoor Cohen

Electronic Theses and Dissertations

Dissertation supervised by Professor Bruce D. Beaver

The oxidative stability of ultra-low sulfur diesel (ULSD) has generally been expected to continuously decline over time. However, recent studies have suggested that it may fluctuate.1-2 In this study, the oxidative stability of stored commercially purchased ULSD was monitored with a methanol extraction method.3 In this methodology, proposed by Hardy and Wechter, fuel blends are extracted with methanol before and after thermal stressing.4 The methanol-soluble layer contains the oxygenated and oxidizable components of the fuel (SMORS) and the change in this mass upon stressing thus represents the oxidative stability of …


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

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

Electronic Theses and Dissertations

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


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

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

Electronic Theses and Dissertations

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