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Legacy Habitat Suitability Of Eastern Oysters (Crassostrea Virginica) In Louisiana: A Prelude To Mississippi River Delta Freshwater Diversions, Tasia Mv Denapolis Dec 2018

Legacy Habitat Suitability Of Eastern Oysters (Crassostrea Virginica) In Louisiana: A Prelude To Mississippi River Delta Freshwater Diversions, Tasia Mv Denapolis

University of New Orleans Theses and Dissertations

The Louisiana oyster industry is greatly impacted by freshwater and sediment diversions that are part of the effort to restore the state’s coastline. A habitat suitability index (HSI) proposes species-habitat relationships that can be instrumental in creating impact assessments and suitability predictions for management as new diversions are implemented. An oyster (Crassostrea virginica) HSI was developed using three variables crucial to oyster sustainability: average annual salinity, minimum monthly salinity, and average salinity during the spawning season. These Legacy HSI visualizations show annual fluctuations in the distribution of zones suitable for oyster cultivation prior to proposed diversions in Pontchartrain and ...


Understanding The Impacts Of Current And Future Environmental Variation On Central African Amphibian Biodiversity, Courtney A. Miller Dec 2018

Understanding The Impacts Of Current And Future Environmental Variation On Central African Amphibian Biodiversity, Courtney A. Miller

University of New Orleans Theses and Dissertations

Global climate change is projected to impact multiple levels of biodiversity by imposing strong selection pressures on existing populations, triggering shifts in species distributions, and reorganizing entire communities. The Lower Guineo-Congolian region in central Africa, a reservoir for amphibian diversity, is predicted to be severely affected by future climate change through rising temperatures and greater variability in rainfall. Geospatial modelling can be used to assess how environmental variation shapes patterns of biological variation – from the genomic to the community level – and use these associations to predict patterns of biological change across space and time. The overall goal of this dissertation ...


Genetic Diversity In An Invasive Clonal Plant? A Historical And Contemporary Perspective, Elliot D. Weidow Aug 2018

Genetic Diversity In An Invasive Clonal Plant? A Historical And Contemporary Perspective, Elliot D. Weidow

University of New Orleans Theses and Dissertations

Introduced populations of Eichhornia crassipes (Pontederiaceae) possess extremely low levels of genetic diversity due to severe bottleneck events and clonal reproduction. While populations elsewhere have been well studied, North American populations of E. crassipes remain understudied. We used Amplified Fragment Length Polymorphism markers to assess genetic diversity and population structure in North American E. crassipes populations. Patterns of diversity over the past fifty years were analyzed using herbarium specimens. Furthermore, we sampled populations across the Gulf Coast of the United States throughout a year to determine contemporary genetic diversity and assess potential seasonal effects. Genetic diversity was found to be ...


Mechanisms Of Invasion And Competition In Anolis Sagrei And Anolis Carolinensis Lizards In Southeastern Louisiana, Jessica R. Edwards Aug 2017

Mechanisms Of Invasion And Competition In Anolis Sagrei And Anolis Carolinensis Lizards In Southeastern Louisiana, Jessica R. Edwards

University of New Orleans Theses and Dissertations

Invasive species can have a variety of effects on the behavior and ecology of native species. Currently in New Orleans, Louisiana, both A. sagrei and A. carolinensis lizards are relatively abundant, but the A. sagrei population is expanding rapidly. I used a combination of laboratory and field studies to investigate factors that might be influencing local dominance of invasive A. sagrei over native A. carolinensis populations, including habitat use, display behavior, interspecific aggressive interactions, and plasticity. When comparing display behavior and habitat use in anole populations across three field sites in southern Louisiana, I found differences in male display behavior ...


Habitat Suitability Modeling For The Mississippi Sandhill Crane, Grus Canadensis Pulla, Linda C. Salande Aug 2016

Habitat Suitability Modeling For The Mississippi Sandhill Crane, Grus Canadensis Pulla, Linda C. Salande

University of New Orleans Theses and Dissertations

In this study, I modeled the suitability of habitat on the Mississippi Sandhill Crane National Wildlife Refuge for the federally endangered Mississippi Sandhill Crane (Grus Canadensis pulla). Habitat type and suitability changed over time due to seasonality of vegetation and succession in the absence of burning. Cranes used highly suitable habitat more in the non-growing than in the growing season, and may have been more constrained by resource availability during winter months. Cranes used some less-suitable areas including cypress drains, which provide roosting sites, and supplemental food plots. The mismatch between predicted quality and crane use suggests that no single ...


Phylogenetic Relationships And Evolution Of Snakes, Alex Figueroa Aug 2016

Phylogenetic Relationships And Evolution Of Snakes, Alex Figueroa

University of New Orleans Theses and Dissertations

Snakes represent an impressive evolutionary radiation of over 3,500 widely-distributed species, categorized into 515 genera, encompassing a diverse range of morphologies and ecologies. This diversity is likely attributable to their distinctive morphology, which has allowed them to populate a wide range of habitat types within most major ecosystems. In my first chapter, I provide the largest-yet estimate of the snake tree of life using maximum likelihood on a supermatrix of 1745 taxa (1652 snake species + 7 outgroup taxa) and 9,523 base pairs from 10 loci (5 nuclear, 5 mitochondrial), including previously unsequenced genera (2) and species (61). I ...


Determining The Pollination Mechanism Of A Problematic Invasive Species In The Gulf South: Triadica Sebifera, Jennifer Wester Clark May 2016

Determining The Pollination Mechanism Of A Problematic Invasive Species In The Gulf South: Triadica Sebifera, Jennifer Wester Clark

University of New Orleans Theses and Dissertations

Understanding the ecology of invasive species is vital to curb the homogenizing of ecosystems, yet the pollination mechanisms of the Chinese tallow tree (Triadica sebifera) in its introduced habitat remain ambiguous. This study examines self-pollination, wind pollination, and flower-visiting insects of tallow in a bottomland hardwood forest and Longleaf pine savannah in the U.S. Gulf South. These data suggest that self-pollination and airborne pollination are possible, but likely rare occurrences, although the possibility of apoxisis was not investigated. Seed production in exclusion experiments was significantly less than in open-pollinated flowers, and wind dispersal of tallow pollen dropped to essentially ...


Chasin’ Tail In Southern Alabama: Delineating Programmed And Stimulus-Driven Grooming In Odocoileus Virginianus, Kyle Heine Aug 2015

Chasin’ Tail In Southern Alabama: Delineating Programmed And Stimulus-Driven Grooming In Odocoileus Virginianus, Kyle Heine

University of New Orleans Theses and Dissertations

This study examined variation in ectoparasite density and grooming behavior of naturally occurring white-tailed deer (Odocoileus virginianus) in southwest Alabama. Stimulus-driven grooming as well as the intraspecific body size and vigilance principles of programmed grooming were tested. During the rut, males had a higher average tick (Ixodidae) density than females and exhibited complete separation of tick parasitism between non-rutting and rutting periods, supporting the vigilance principle. Stimulus-driven grooming was supported, as both fawns and yearlings had significantly higher fly (Hippoboscidae) and combined fly/tick densities than adults, and fawns oral groomed at a significantly higher rate than adults, even in ...


Role Of Ime4 Protein In Pho Regulon Of S.Cerevisiae., Jenisha Ghimire Aug 2015

Role Of Ime4 Protein In Pho Regulon Of S.Cerevisiae., Jenisha Ghimire

University of New Orleans Theses and Dissertations

In the yeast Saccharomyces cerevisiae, the IME4 methyltransferase, interacts genetically with methyl binding protein, Pho92, to affect the expression of PHO regulon target genes. Cells mutant in IME4 or PHO92 show increases in the RNA abundance of PHO regulon target genes. The increase in the RNA abundance of the PHO regulon target genes is not additive in the cells double mutant in IME4 and PHO92. Hence, Ime4 and Pho92 interact in a single pathway in PHO regulon. Surprisingly, cells overexpressing IME4 and MUM2 shows increase in some PHO regulon target genes, indicating that IME4 affects the PHO regulon target genes ...


Phylogenetics And Mating System Evolution In The Southern South American Valeriana (Valerianaceae), Lauren A. Gonzalez Aug 2014

Phylogenetics And Mating System Evolution In The Southern South American Valeriana (Valerianaceae), Lauren A. Gonzalez

University of New Orleans Theses and Dissertations

Species of Valerianaceae in South America represent one of the best examples of rapid diversification on a continental scale. The phylogeny of Valerianaceae has received a lot of attention within the last 10 years, but relationships among the South American species are fairly unresolved. Results from previous studies have not been well resolved with traditional genetic markers, most likely due to its recent and rapid radiation. Species in this clade exhibit a variety mating systems and inflorescence types. For the first part of this research I used several traditional plastid markers, and 3 new low copy nuclear markers to better ...


Transcriptional Co-Repressor Response Of Arabidopsis Thaliana To Different Abiotic Stress, Bhuwan Guragain Dec 2013

Transcriptional Co-Repressor Response Of Arabidopsis Thaliana To Different Abiotic Stress, Bhuwan Guragain

University of New Orleans Theses and Dissertations

Plants adapt to the complex environmental challenges by regulating their gene expression. Analyses of plant genomes have identified many genes that are either expressed or repressed during environmental stress. However we do not have much information on gene repression. Transcriptional repression in Arabidopsis thaliana is caused by co-repressors that lack the DNA binding domain and are recruited by transcription factors to regulate target gene expression. The Sridhar lab has identified co-repressors SLK1, SLK2, and LUH, which prevent the expression of stress response genes under non-stress conditions. Arabidopsis transgenic lines expressing the GUS under the control of co-repressor’s promoter were ...


Statistical And Comparative Phylogeography Of Mexican Freshwater Taxa In Extreme Aquatic Environments, Lyndon M. Coghill Dec 2013

Statistical And Comparative Phylogeography Of Mexican Freshwater Taxa In Extreme Aquatic Environments, Lyndon M. Coghill

University of New Orleans Theses and Dissertations

Phylogeography aims to understand the processes that underlie the distribution of genetic variation within and among closely related species. Although the means by which this goal might be achieved differ considerably from those that spawned the field some thirty years ago, the foundation and conceptual breakthroughs made by Avise are nonetheless the same and are as relevant today as they were two decades ago. Namely, patterns of neutral genetic variation among individuals carry the signature of a species’ demographic past, and the spatial and temporal environmental heterogeneity across a species’ geographic range can influence patterns of evolutionary change. Aquatic systems ...


The Effects Of Ecological Context And Individual Characteristics On Stereotyped Displays In Male Anolis Carolinensis, Catherine Policastro Dec 2013

The Effects Of Ecological Context And Individual Characteristics On Stereotyped Displays In Male Anolis Carolinensis, Catherine Policastro

University of New Orleans Theses and Dissertations

Displays are ubiquitous throughout the animal kingdom. While many have been thoroughly documented, the factors affecting the expression of such displays are still not fully understood. We tested the hypotheses that display production would be affected by ecological context (i.e. the identity of the receiver) and intrinsic qualities of the signaler (i.e. heavyweight and lightweight size class) in the green anole lizard, Anolis carolinensis. Our results supported these predictions and show that a) ecological context, specifically displaying to conspecifics, has the greatest impact on display production; b) size class influenced display rate with heavyweight males displaying more to ...


Effects Of Prescribed Burns On Grassland Breeding Birds At Mississippi Sandhill Crane National Wildlife Refuge, Elizabeth A. Ruffman Dec 2013

Effects Of Prescribed Burns On Grassland Breeding Birds At Mississippi Sandhill Crane National Wildlife Refuge, Elizabeth A. Ruffman

University of New Orleans Theses and Dissertations

There has been a critical decline in grassland bird populations due to habitat fragmentation and deterioration, and suppression of natural fires. Alteration of the disturbance cycle may lead to changes in vegetation structure and thus habitat suitability for breeding grassland birds. Management practices at the Mississippi Sandhill Crane National Wildlife Refuge, including the use of prescribed fire, are in need of evaluation. My study asked what frequency of prescribed burns is necessary to support breeding grassland birds and whether vegetation structure varies among burn units. In this study, bird abundance and species richness did not differ significantly among burn units ...


Assessing The Responses Of Adult, Juvenile, And Larval Fish Assemblages To The Closure Of The Mississippi River Gulf Outlet, An Artificial Tidal Pass In Southeastern Louisiana, Rebecca Weatherall Cope Dec 2013

Assessing The Responses Of Adult, Juvenile, And Larval Fish Assemblages To The Closure Of The Mississippi River Gulf Outlet, An Artificial Tidal Pass In Southeastern Louisiana, Rebecca Weatherall Cope

University of New Orleans Theses and Dissertations

The creation of the Mississippi River Gulf Outlet (MRGO) in 1963 by the U.S. Army Corps of Engineers (USACE) represents one of the most catastrophic, anthropogenic stressors ever to impact the Lake Pontchartrain estuary in southeastern Louisiana, USA. The artificial tidal pass provided a direct route from the Gulf of Mexico to New Orleans. It allowed for high saline waters to enter Lake Pontchartrain, resulting in detrimental changes to the biotic community of the Lake and surrounding wetland areas. In July 2009, the USACE closed the MRGO in hopes of restoring natural ecosystems. This study assesses changes in the ...


A Study On The Regulation Of Amino Acids And Glucose Sensing Pathways In Saccharomyces Cerevisiae, Mengying Chiang Aug 2013

A Study On The Regulation Of Amino Acids And Glucose Sensing Pathways In Saccharomyces Cerevisiae, Mengying Chiang

University of New Orleans Theses and Dissertations

Nutrient availability regulates eukaryotic cell growth. This study focuses on two signaling pathways, involved in sensing amino acids and carbon sources, which allow cells to respond appropriately to their presence. The first part of this study shows that Ssy1, a plasma membrane localized sensor in the Ssy1-Ptr3-Ssy5 (SPS) amino acid sensing pathway, can detect 19 common L-amino acids with different potencies and affinities based on the physiochemical structure of amino acids. Substituents around alpha carbon are critical for amino acid sensing by Ssy1. Furthermore, a high concentration of cysteine is toxic to cells. Inactivation of SPS signaling confers resistance to ...


Validation Of Antibodies Used To Study Hypoxia Inducible Factors In Two Species Of Fundulus, Jenna D. Hill May 2013

Validation Of Antibodies Used To Study Hypoxia Inducible Factors In Two Species Of Fundulus, Jenna D. Hill

University of New Orleans Theses and Dissertations

Hypoxia inducible factors (HIFs) are transcription factors and the master regulators of oxygen-dependent gene expression in animals. The focus of this thesis is the distribution of HIF protein in tissues of the fish Fundulus heteroclitus and F. grandis, two widespread species that occur in naturally hypoxic waters. Polyclonal antibodies against HIF-1α, HIF-2α, and HIF-3α were tested on proteins made in vitro and on extracts made from several tissues of normoxic and hypoxic fish. Antibodies against HIF-1α and 3α bound specifically to full length protein made in vitro, and produced bands on western blots of nuclear extracts of near the expected ...


Regulation Of The Target Of Rapamycin Signaling Pathway In Saccharomyces Cerevisiae, Tammy Pracheil May 2013

Regulation Of The Target Of Rapamycin Signaling Pathway In Saccharomyces Cerevisiae, Tammy Pracheil

University of New Orleans Theses and Dissertations

An integrative, biochemical, genetic, and molecular biology approach utilizing gene manipulation, gene knock outs, plasmid based protein expression, and in vivo protein localization of fluorescence tagged proteins was employed to determine the function of an essential protein, Lst8, in TORC1 and TORC2 signaling and a previously uncharacterized complex, the Far3-7-8-9-10-11 complex (Far complex) in the budding yeast, Saccharomyces cerevisiae. Mutations in SAC7 and FAR11 suppressed lethality of both lst8 and tor2-21 mutations but not TORC1 inactivation, suggesting that the essential function of Lst8 is linked only to TORC2.

Far11, a component of a six-member complex, was found to interact with ...


Occurrence And Genetic Diversity Of Lemon Sharks (Negaprion Brevirostris) At A Nursery Ground At The Chandeleur Islands, Louisiana., Jonathan F. Mckenzie May 2013

Occurrence And Genetic Diversity Of Lemon Sharks (Negaprion Brevirostris) At A Nursery Ground At The Chandeleur Islands, Louisiana., Jonathan F. Mckenzie

University of New Orleans Theses and Dissertations

Anecdotal evidence suggested that immature lemon sharks (Negaprion brevirostris) occur at the Chandeleur Islands in southeastern Louisiana. From May 2009 to August 2011, the Nekton Research Laboratory at the University of New Orleans regularly sampled habitats at the Chandeleur Islands to confirm the presence of immature individuals of this species. During these efforts, 147 immature lemon sharks (neonates, young-of-the-year, and juveniles) were collected. Each shark was PIT tagged and a tissue sample was taken for genetic analyses. Sizes ranged from 56 – 177 cm total length. Sharks showed a preference for sandy substrate and smaller individuals showed significant preference for shallow ...


Comparing Biology Grades Based On Instructional Delivery And Instructor At A Community College: Face-To-Face Course Versus Online Course., Amanda Rosenzweig Dec 2012

Comparing Biology Grades Based On Instructional Delivery And Instructor At A Community College: Face-To-Face Course Versus Online Course., Amanda Rosenzweig

University of New Orleans Theses and Dissertations

Through distance learning, the community college system has been able to serve more students by providing educational opportunities to students who would otherwise be unable to attend college. The community college of focus in the study increased its online enrollments and online course offerings due to the growth of overall enrollment. The need and purpose of the study is to address if there is a difference in students’ grades between face-to-face and online biology related courses and if there are differences in grades between face-to-face and online biology courses taught by different instructors and the same instructor. The study also ...


Birds In Residential Metropolitan New Orleans Neighborhoods And Their Relationships To The Batture And Yard Vegetation, Ruth A. Guymon Aug 2012

Birds In Residential Metropolitan New Orleans Neighborhoods And Their Relationships To The Batture And Yard Vegetation, Ruth A. Guymon

University of New Orleans Theses and Dissertations

Metropolitan New Orleans Neighborhoods were surveyed in order to determine how bird populations responded to distance from the batture, percent canopy cover, stem counts, and understory vegetation. Surveys were conducted in the spring and summer of 2010. It was found that batture birds, urban birds, and pooled birds all had greater species richness and abundance in the spring in areas with more canopy cover, higher stem counts, more understory vegetation, and distances closer to the batture. In the summer, batture birds had greater richness and abundance in areas with more canopy cover, higher stem counts, and more understory cover. This ...


An Evaluation Of Submersed Aquatic Vegetation Transplanting Methods For Lake Pontchartrain Restoration, Donald Anthony Rodrigue Jr. May 2004

An Evaluation Of Submersed Aquatic Vegetation Transplanting Methods For Lake Pontchartrain Restoration, Donald Anthony Rodrigue Jr.

University of New Orleans Theses and Dissertations

The general goals of this study were to evaluate transplant methods for Lake Pontchartrain submersed aquatic vegetation (SAV) restoration, and to compare survival and expansion of transplanted SAV among four sites. Two experiments were conducted from summer 2000 through spring 2001 at two north shore and two south shore sites in Lake Pontchartrain. Experiment 1 involved testing the effects of transplanting with matting, staples, exclosures, and interspecific interaction on survival and expansion of Ruppia maritima and Vallisneria americana transplants in Lake Pontchartrain. Experiment 2 involved testing the effects of transplanting with matting, staples, and plugs on Ruppia survival and expansion ...