Biology Commons^™

Environmental Sensitivity Of Maternal And Offspring Phenotype In The Green Anole (Anolis Carolinensis) Lizard, Jamie Marks

LSU New Orleans Theses and Dissertations

Animals dynamically invest their acquired energetic resources into fitness-related traits, and life-history trade-offs occur when limited resources are invested in a given trait at the expense of another. The phenotypic effects of life history trade-offs are well documented, but the mechanisms facilitating these trade-offs are poorly understood. One such mechanism is the insulin/insulin-like signaling (IIS) network, and specifically its two primary hormones: insulin-like growth factor 1 (IGF1) and insulin-like growth factor 2 (IGF2). IGF1 is well-characterized but IGF2 is severely understudied, though it is present in nearly all amniotes and sometimes expressed at higher levels than IGF1 in adulthood. I …

Larval Fish Export In Response To Varying Compensating Gate Discharge At The Sault Rapids, St. Marys River, Signe F.K. Vandrunen

All NMU Master's Theses

The St. Marys River (SMR) forms the border between Michigan, USA and Ontario, Canada connecting lakes Superior and Huron. Discharge is controlled by a compensating gate system upstream of the SMR rapids. Because spring and summer discharge fluctuates widely, resource managers required information on how flow variability influences larval fish drift. I estimated annual larval fish export in relation to variable discharge during 2018-2021 and compared results to published habitat model predictions. Mean discharge and water temperature were lowest in 2021 and highest in 2019. Water warming rates during high discharge differed from low discharge trends. Across years, I identified …

Influence Of Plant Density On Rainfall Interception By Spartina Alterniflora, Hannah K. Longaberger

Honors College Theses

Abstract

Spartina alterniflora is an abundant plant in eastern US and Gulf coast salt marshes; it is important in maintaining a diverse ecosystem. Salt marshes are impacted by rainstorms, which may affect erosion events. This project examined the partitioning of rainfall on single plants of various sizes and on central plants within different canopy densities of S. alterniflora. By calculating the rain stemflow (SF), throughfall (TF), and water adhered to the stem in S. alterniflora, we gained insight to rainfall partitioning with different plant features. My research found no statistically significant relationship between different plant features and SF, TF, …

Seqcode: A Nomenclatural Code For Prokaryotes Described From Sequence Data, Brian P. Hedlund, Maria Chuvochina, Philip Hugenholtz, Konstantinos T. Konstantinidis, Alison E. Murray, Marike Palmer, Donovan H. Parks, Alexander J. Probst, Anna-Louise Reysenbach, Luis M. Rodriguez-R, Ramon Rossello-Mora, Iain C. Sutcliffe, Stephanus N. Venter, William B. Whitman

Life Sciences Faculty Research

Most prokaryotes are not available as pure cultures and therefore ineligible for naming under the rules and recommendations of the International Code of Nomenclature of Prokaryotes (ICNP). Here we summarize the development of the SeqCode, a code of nomenclature under which genome sequences serve as nomenclatural types. This code enables valid publication of names of prokaryotes based upon isolate genome, metagenome-assembled genome or single-amplified genome sequences. Otherwise, it is similar to the ICNP with regard to the formation of names and rules of priority. It operates through the SeqCode Registry (https://seqco.de/), a registration portal through which names and …

The Utilization Of Crispr/Cas9 In Monogenic Disorders Authors, Shauna M. Mellor

Spectra Undergraduate Research Journal

This paper is a literature review of various scientific research papers, exploring the recent scientific advancement in the field of genetic engineering. The research presented is a foundational tool, building awareness on the implications of CRISPR/ Cas9 technology. CRISPR/ Cas9 was first discovered through the study of bacterial immune systems, fighting against viral infections. Manipulation of the Cas9 protein would eventually lead to target specific, gene-altering medicines for human organisms. CRISPR/ Cas 9 technology has begun to show promise as an effective treatment for certain monogenic disorders. Despite this, time is required before its efficacy as a proven genetic treatment …

Effects Of Mass Death On Community Structure And Ecosystem Function, Abby Kimpton Jones

Theses and Dissertations

Death and decomposition are natural processes that are generally well-understood. However, large events of death, such as mass mortality events (MMEs) are increasing in frequency and their impacts on the ecosystem are largely unknown. These events may have both bottom-up effects from increased nutrient input as well as top-down effects from loss of an ecological functional group by the affected population. Different functional MMEs may result in different top-down effects, creating cascading effects. In Chapter 1, I test the hypothesis that scavenger and herbivore simulated MMEs generate novel bottom-up and top-down effects. Results indicate that MMEs have a significant effect …

Chemically Induced Phytoextraction Of Lead (Pb) Contaminated Soil By Switchgrass (Panicum Virgatum L.), Assisted With Bap And Nta Applications, Genna Hart

Master of Science in Integrative Biology Theses

The accumulation of lead (Pb) deposits in soil is a growing global concern. Phytoextraction of Pb-contaminated soil can be enhanced by soil chelation to increase the bioavailability of Pb. In the initial study nitrilotriacetic acid (NTA) 5mM, the alkylpolyglucoside (APG) Triton X-100 (2%), and nano-silica were applied to switchgrass (Panicum virgatum L.) growing in 5L pots of Pb-contaminated soil. The second experiment used 10mM NTA, the alkylpolyglycoside Triton X-100 (2%), foliar application of the plant growth regulator 6-benzylaminopurine (BAP) twice per week, Triple-12® nutrients, and Infuse™ a soil fungicide which were applied to switchgrass Plants were grown in a controlled …

The Influence Of Land Coverage And Soil Chemical Factors On Soil Bacterial Community Diversity And Structure In Cedartown, Ga, Usa, Jake Smith

Master of Science in Integrative Biology Theses

Heavy metals pose serious threats to organisms due to their mobility and solubility in soil. Bacteria communities are vulnerable to heavy metal stress, but the response of different bacterial groups may vary depending on the level and type of heavy metal contamination. When subjected to heavy metal stress, many bacterial species or populations may become extirpated, while some may survive to form the foundations of a new microbial community. A study of the bacterial community at a lead (Pb) contaminated study site in Cedartown, GA, found that the microbiome in the Pb contaminated soil had significantly lower species richness. But …

Heavy Metal Distribution Across Three Georgia Estuaries Using Coastal Sharks As Sentinel Species, Allyson Stiles

Master of Science in Integrative Biology Theses

Estuaries are transitional environments that play key roles in coastal ecosystem functioning by providing essential habitats to ecologically important plant and animal species. Estuaries are exposed to a number of anthropogenic impacts, including heavy metal contamination from human activities. However, few studies have examined heavy metal distribution within Georgia’s estuaries and how intact salt marsh ecosystems could play a role in filtering and sequestering contaminants, such as Mercury (Hg). This thesis examined blood total mercury (THg) concentrations of four coastal shark species and concentrations of five heavy metals (Hg, As, Cr, Cu, and Pb) within the water and sediments of …

The Effects On Soil Fungal Community Of Excluding Select Above-Ground Herbaceous Species In A Montane Longleaf Pine Savanna Restoration Area, Sean Davis

Master of Science in Integrative Biology Theses

Due to anthropogenic pressures, by the 1990s longleaf pine forests were at 3% its peak area. Restoration is difficult as vegetation communities constitute a mosaic across the longleaf range. Hence, vegetation description is important wherever longleaf pine communities exist. Vegetation strongly associates with specific soil fungi operational taxonomic units (OTUs) and description of longleaf pine ecosystems are incomplete without description of microbial taxa.

My goals were to begin describing soil fungal communities of the longleaf pine at Sheffield Wildlife Management Area (SWMA) and describe changes to the fungal community after the removal of dominant plants in a longleaf savanna. I …

Assessing The Indigenous Arbuscular Mycorrhizal Fungi (Amf) Community Associated With Sea Oats Along The Georgia Coast At Jekyll And Tybee Islands, Kylie Stover

Master of Science in Integrative Biology Theses

Coastal sand dunes are fragile ecosystems that serve as natural defenses to protect the adjacent mainland by absorbing the impacts and energy from severe storms. Different efforts have been taken to restore coastal sand dunes, focusing on foredunes. However, there are many strategies involved with coastal restoration and one superior technique has not been found to be the best. Arbuscular mycorrhizal fungi (AMF) supply a range of limiting nutrients (N, P, Fe, and Zn) to the host plant while improving dune stability. This study aimed to assess and compare the diversity of the indigenous AMF community associated with sea oats …

Regional-Scale Climate-Induced Variation In Ant Physiology And Morphology, Daniel E. Murphy

Biology Theses

The biology of ectotherms such as insects is influenced by ambient thermal conditions. Ants are a ubiquitous and ecologically important group of insects and are well-established as bioindicators of thermal conditions. Ants are sensitive to the thermal extremes that vary with latitude, elevation, and land use, and these thermal gradients influence their spatial and temporal distributions. As a result, ants have evolved physiological and morphological thermal adaptations in response to the thermal environment of their habitats. These adaptations include increased physiological and morphological tolerance for temperature extremes. In Western New York (WNY), temperatures are temporally and spatially heterogeneous, changing with …

Chromosome Number Evolution, Phylogeography, And The Effects Of Climate Change On Species Distributions In Polyploid Plant Systems, Courtney H. Babin

LSU New Orleans Theses and Dissertations

Polyploidy, a term used to describe organisms with cells having more than two paired sets of chromosomes, is a significant driver of diversification among land plants. Over a century of research has advanced our understanding of polyploidization in some taxa, but polyploid organisms remain understudied. In this dissertation, I investigate chromosome number evolution, phylogeographic structure, genetic differentiation, and the effects of climate change on ploidy level distribution using polyploid plant systems. In the first chapter, I inferred a molecular phylogeny of Allium, an economically important genus that includes cultivated crops and ornamentals, to investigate evolutionary transitions in chromosome number …

Haplotype-Informed Allelic Imbalance Detection From Rna In Cancer, Zuhal Ozcan

Dissertations and Theses (Open Access)

Comprehensive genomic and transcriptomic characterization of tumors has uncovered enrichment for distinct aneuploidy and expression patterns, demonstrating the utility of molecular based classification of cancers and their subtypes. Existing cohorts with transcriptomic profiling from next-generation sequencing contain an untapped potential to also relate genomics with rich clinical phenotypes. Yet, derivation of somatic copy number and expression profiles from analyses of RNA has remained elusive. Further, DNA analysis in these cohorts is not always feasible due to limited tissue availability or financial constraints. Here, we present a statistical approach that overcomes these challenges using haplotype information to aid detection of somatic …

Non-Photic Mechanisms Of Entrainment In Bmal1 Deficient Conditions, Jamie Tran

Dissertations and Theses (Open Access)

Maintaining our internal circadian (i.e. 24 -hour) clock is imperative to our daily biological and mental well-being. Large epidemiological studies have shown that disruptions of our circadian rhythms can lead to poor mental health, metabolic diseases, and various types of cancer. Various external cues that have become a part of the modern times such as electricity, shift -work, rapid travel across various time zones, easier access to nutritionally unbalanced food items, and various rigid social demands have deleterious effects on our internal clock, and generally reduce robustness of the circadian clock. The two following projects aim to examine two fundamental …

Patterns Of Evolutionary Conservation And Divergence In The Short-Term Hyposalinity Stress Response Of A Euryhaline Diatom, Skeletonema Marinoi, Kathryn Judy

Graduate Theses and Dissertations

Survival under fluctuating environmental conditions, such as those increasing in frequency and magnitude under environmental change, requires a successful response to stress. Interspecific differences in stress responses may result in differential survival of species, even within a lineage. Diatoms may constitute one such lineage, as salinity tolerance among extant species is diverse, and the observation of frequent historic habitat transitions between marine and freshwater environments indicates that diatoms successfully mitigated (low) salinity stress in the past, followed by adaptation and diversification over evolutionary time scales. To understand to what extent the diatom hypoosmotic stress response consists of conserved and variable …

Evaluating The Impact Of Intersecting Research And Outreach Marine Science Programs On Elementary And Undergraduate Students, Randi J. Sims

All Theses

Climate change is one of the most destructive forces our ocean is currently experiencing. Despite this, many students are not taught the basics of climate change science and ocean literacy in public school systems. My work seeks to combat these deficits through educational experiences in marine science for undergraduate and local elementary students through three studies incorporating marine-science based research and outreach. (1) Through undergraduate marine science research and outreach, students enrolled for long durations or with positive mentorship increased their conceptual understanding of marine science concepts, altered their attitudes towards climate change and science, and were more likely to …

Connecting Above- And Belowground Effects Of Climate Warming On Bumble Bee Health, Francis Mullan

Master of Science in Integrative Biology Theses

Climate warming has been identified as one of the primary factors causing worldwide pollinator declines. One of the most at-risk groups of pollinators is bumble bees (Bombus spp.). Bumble bees are common, widespread, and key pollinators of a wide range of crops and wild plants. Although studies have examined the thermal physiological traits of individual bumble bees to understand how they may be impacted by climate warming, little to no studies have examined how climate warming may impact whole bumble bee colonies both in their ability to thermoregulate their nest for their brood or in their ability to forage …

Consequences Of Gulf Of Mexico Estuarine Tropical Cyclone Disturbance Regimes For Fish Assemblage Dynamics Conditionally Depend On Life-History Traits And Niche Characteristics, Stephen Edward Potts

LSU Doctoral Dissertations

Tropical cyclones (TC) are intense, localized disturbances that can potentially cause extensive damage to ecosystems. This dissertation is motivated by a need for interdisciplinary study of TC-ecosystem dynamics with applications to ecology, geography, and analytical methodology. I explore concept linkages between TC dynamics and ecosystems to characterize TC-ecosystem relationships as ecological disturbance regimes. This dissertation tests hypotheses and relationships of TC effects on estuarine fish assemblages in the north-western Gulf of Mexico. I explore concepts in TC-ecosystem relationships to link biotic dynamics with physical disturbance.

In Chapter 2, I compared spatial performance of generalized linear models (GLMs) and generalized additive …

Ant Cuticle Microsculpture: Diversity, Classification, Evolution, And Function, John Paul Hellenbrand

Master of Science in Integrative Biology Theses

My thesis covers the intricacies of ant microsculpture diversity, classification, evolution and function. To do this, the thesis is organized into two chapters. The first chapter is a review of ant cuticle and microsculpture diversity as well as including analyses examining the evolution and lability of microsculpture traits. I then review the literature for functional hypotheses related to ant microsculpture. The second chapter explores the relationship of microsculpture and important morphological, physiological, and ecological traits to evaluate support for functional hypotheses.

The Evolution Of Honeycomb, Grace Cope

Master of Science in Integrative Biology Theses

The regular cells of honeycomb nests have fascinated scholars and mathematicians for millennia. In 36BC, the Roman scholar Marcus Terentius Varro first proposed the “honeycomb conjecture,” in which he postulated that bees build their comb using hexagons because it is the shape that requires the least amount of material to divide space into equal portions. Since this time, honeycomb has been used by engineers in applications that range from skyscraper supports to impact absorbers inside the feet of the lunar lander during the first moon missions, but mysteries remain about the biological origins of honeycomb and the mechanical properties of …

Noxious Cellular Injury Triggers An Oxidative Stress Gene Response, Shawyun Khoshneviszadeh

Master of Science in Integrative Biology Theses

Wound and regeneration involves a series of complex processes that can induce oxidative stress by elevating intracellular reactive oxygen species (ROS) levels. In this study, we used RNA-seq and qPCR to examine the molecular signature of Human Embryonic Kidney cells (HEK-293T) stimulated with Crotalus atrox (CA) venom. NGS data was assembled and annotated utilizing the Illumina paired-end RNA-seq approach with software packages HISAT2 and StringTie. Results showed 243 genes were differentially expressed (106 upregulated, 137 downregulated) between CA venom stimulated and non-stimulated cells (p<0.05). HEK-293T stimulated with CA venom for 4 hours showed an increase in the expression of oxidative stress response genes (e.g., TOMM6, EGR (1,2,3), HSP70 (1A, 1B), SPRY4, ETV5, and EMP1) (Fold-Change (fc) >2.0). Significantly downregulated genes were associated with many novel transcripts/proteins such as AC117378, AD000671, and AC023509. …

Studying Tissue Specific Diversity Of Splicing Regulator Muscleblind, Davron Hanley

Master of Science in Integrative Biology Theses

The muscleblind (mbl) family of RNA-binding proteins regulates alternative splicing, determining mRNA transcript composition for various types of tissue, and has been implicated in myotonic dystrophy. The mbl gene is subject to alternative splicing in Drosophila, leading to multiple isoforms, and has several paralogs in humans. Mbl proteins vary significantly in length, although the significance of such diversity and the role of specific isoforms have not been fully explored. Using immunofluorescence microscopy and polyclonal serum, we analyzed Mbl protein expression across adult Drosophila tissues. Mbl was detected in various locations, including the brain, gonads, muscle, and gut epithelium. Skeletal muscles …

Cross-Modal Perception Of Identity By Sound And Taste In Bottlenose Dolphins, Jason N. Bruck, Sam F. Walmsley, Vincent M. Janik

Faculty Publications

While studies have demonstrated concept formation in animals, only humans are known to label concepts to use them in mental simulations or predictions. To investigate whether other animals use labels comparably, we studied cross-modal, individual recognition in bottlenose dolphins (Tursiops truncatus) that use signature whistles as labels for conspecifics in their own communication. First, we tested whether dolphins could use gustatory stimuli and found that they could distinguish between water and urine samples, as well as between urine from familiar and unfamiliar individuals. Then, we paired playbacks of signature whistles of known animals with urine samples from either the same …

Sodium Mediates Developmentally Plastic Responses In Plants And Herbivores, Luis Santiago-Rosario

LSU Doctoral Dissertations

Sodium plays a crucial role in organismal performance, trophic-level interactions, and eco-evolutionary dynamics. For plants, sodium impacts osmoregulation, growth, and water uptake. For animals, sodium is essential influencing osmoregulatory processes, muscle and neural development, and blood regulation. My dissertation aims to disentangle why sodium mismatch affects resource-consumer interactions and its influence on morphological and behavioral plasticity. First, I identified how sodium impacts plant performance and sodium accumulation strategies. I initially focused my research on understanding how increasing substrate sodium affects plant growth and tissue sodium accumulation strategies in controlled settings using a systematic review approach. I found that saltier plants …

A Review Of Current Methods In Avian Dietary Analysis And Their Integrated Application To Characterize The Trophic Niche Of Louisiana Waterthrush (Parkesia Motacilla)., Brandon Hoenig

Electronic Theses and Dissertations

Characterizing a species’ dietary composition presents an avenue to understand many facets of its ecological niche and can provide essential information for the species’ long-term conservation. To date, the vast majority of diet studies have relied on direct identification of prey during foraging observations or from diet samples to characterize the dietary habits of birds. However, advancements in laboratory-based approaches have revolutionized the field of trophic ecology by allowing researchers to indirectly infer dietary habits with higher resolution across greater time scales. Here, I apply two of these laboratory-based techniques, namely DNA metabarcoding and stable isotope analysis, to characterize the …

Physiological Costs Of Total Cholesterol In European Starlings Across An Urban To Rural Gradient, Courtney Linkous

Master of Science in Integrative Biology Theses

Urban areas—characterized by high human densities and associated buildings and impermeable surfaces—are increasing globally and represents a leading threat to wildlife that is drastically altering the natural resources they are accustomed to. Prior studies suggest that living in urban habitats can cause wildlife to show increased cholesterol levels; in biomedical research, elevated cholesterol is linked to disease, but the consequence of elevated cholesterol in wildlife remains unclear. We measured total cholesterol in European starlings (Sturnus vulgaris)—an urban adapted species—across an urban and a rural site. We ask: (1) do urban starlings have elevated cholesterol, (2) does elevated cholesterol …

Pilfering Passerines? Inter-Class Competition: A New Direction In Foraging Ecology, Shannon Gillen

Masters Theses, 2020-current

Life in the epigeal layer below leaf litterfall often goes unexplored. Shrews (Soricidae, 1910) have foraged in this microhabitat for millions of years, carving out an existence in harsh habitats around the world, ranging from the tropics to subarctic boreal tundra. Two shrew species that inhabit the Shenandoah Valley of Virginia, the least shrew (Cryptotis parva) and northern short-tailed shrew (Blarina brevicauda), were the focus of this study. Shrews make epigeal foraging trails while they continually forage for food, and caching is a way to save this food for times of low and sporadic food availability. …

A Neuromuscular Look Into Genetics Of Muscle Aging, Christina Talley

Master of Science in Integrative Biology Theses

As individuals age throughout their life, they experience muscle tissue loss that impacts their quality of life such as a decrease in their physical capabilities and sometimes even their mental capacity. The process of muscle aging is the key point of this study. This involves the individual’s muscles and the motor neurons that control them. Skeletal muscles are used daily to maintain posture, stand, walk, etc. Throughout a lifetime these muscles undergo damage and need to be repaired. When the muscles are repaired, they express physical changes. The tissue shrinks in size and eventually the composition of the tissue is …

Determining The Distribution Of Elemental Compounds And Oxidative Potential Across Fine Particulate Matter (Pm2.5) Filters, Allie Michelle Sidwell

Honors Theses

Fine particulate matter (PM_2.5) is a complex mixture of particles and sorbed chemicals that poses serious, adverse effects on human health such as increasing cardiovascular and respiratory morbidity and mortality. There is ongoing research into the impacts of PM_2.5 of differing chemical compositions, sampling location, and the mechanisms for the observed health effects. To conduct these analytical and toxicology studies of PM_2.5, researchers often split filters into sections. This process allows multiple, often destructive, assays to be performed. Our previous research showed chemical composition differences across PM_2.5 filters. The goal of our study was …