Biology Commons^™

The Macroevolution Of Diadromous And Non-Diadromous Clupeiformes., Lindsey Dehaan

Honors Theses

Migration is a common life history strategy across the animal tree of life. This behavior is energetically demanding and may trigger strong selection for the evolution of an optimal ecomorphology to lessen energetic costs, yet the ecomorphology of migratory aquatic species remains poorly understood. Previous studies have demonstrated that migratory fishes exhibit predictable phenotypic patterns in body size evolution in response to evolving migration: migratory fishes are larger than non-migratory fishes. Migratory fishes may also have functional traits (e.g. fin shape) associated with locomotion that have experienced similar selective forces and exhibit predictable evolutionary patterns, resulting in migratory lineages sharing …

Is Natural Selection Shaping Florida Manatees? : An Investigation Into The Body Shapes Between The Subspecies Of The West Indian Manatee, Juliane Johnson

Honors Theses

The West Indian manatee (Trichechus manatus) is currently divided into two subspecies: the Antillean (T. m. manatus) and Florida manatee (T. m. latirostris). Florida manatees are found at the northern extreme of the species range, primarily inhabiting the waters around the Florida peninsula, while the Antillean manatee inhabits the remaining range from the Caribbean islands to eastern Brazil. Only in the range of the Florida manatee does water temperature drop below 20°C during the winter, and these manatees have to seek warm water refuge for thermal regulation. Allen's rule predicts that in colder climates animals will adapt to have smaller …

Oil Preference In Ants And Arthropod Diversity In Urban Environments, Itzel Guzman-Hernandez

Honors Theses

The success of certain ant species in urban areas is largely unknown. Available food in the environment could affect the composition of ants in urban areas due to a possible relationship between ant physiology and diet. I tested the oil preference of ants as a function of available arthropod prey in urban environments. I hypothesized that as arthropod diversity decreased, ant abundance at oil baits would decrease. Oil is an important nutrient that can affect ant body functions and activities. Ant foraging activities have been found to be affected by lipid depletion. A food source where ants can obtain oil …

Antibiotic Resistant Bacteria Isolated From Michigan Birds - A High School Learning Experience, Cody Benfant

Honors Theses

Bacteria, extremely small prokaryotic cells, are everywhere throughout the world. One striking thing about bacteria is their size: comparing a 2-micrometer bacterial cell to a 6-foot-tall human is similar in scale to comparing a 6-foot-tall human to the distance between Chicago, IL and Denver, CO! Despite their small size, bacteria are found in almost every ecosystem and environment imaginable. From deep sea hydrothermal vents to the clouds miles in the sky, there are trillions of bacteria flourishing in all of Earth’s ecosystems, performing many important functions in global nutrient cycles. While the majority of bacteria are beneficial to humans, …

Diurnal Variation In Co2 Efflux By Pine Seedlings And Root-Associated Mycorrhizal Fungi, Richard Easterling

Honors Theses

This project was part of a larger experiment conducted by Amber Horning and Jason Hoeksema in the Department of Biology at the University of Mississippi, which was set up to investigate variation (over time, and with different light levels) in resource exchange between pine seedlings and two different species of ectomycorrhizal (EM) fungi. The experiment was conducted in a growth chamber, with mycorrhizal pine seedlings growing in plexiglass "mycocosms." I worked with two EM fungal species (Rhizopogon roseolus and Pisolithus arhizus, hereafter "Rhizopogon" and "Pisolithus"), which were collected locally near Oxford, Mississippi under loblolly pine. I selected a subset of …

Auditory Radiation And Cognitive Decline: Probabilistic Tractography Study, Adryanna Tucker

Honors Theses

The relationship between hearing loss and Alzheimer’s disease has been studied for many years. Previous studies have shown a negative correlation between the two. In our study, we investigated the relationship between the strength of the auditory radiation connections and the severity of cognitive decline. To do so, we assessed probabilistic tractography using DTI data of the primary auditory pathway. Further, we assessed the level of cognition using the Alzheimer's Disease Assessment Scale-Cog to determine the relationship between the auditory connections assessed in each patient and that patient’s level of cognitive decline. We found that FA and AD were positively …

An Investigation Of Possible Reservoirs Of Lymphoproliferative Disease Virus Of Turkeys In Mississippi, Walker Hyche

Honors Theses

Emerging infectious diseases are a problem among wildlife and domestic populations. It is critical for these diseases to be studied. Lymphoproliferative disease virus is a retrovirus affecting turkeys and chickens. Prior research originally identified the virus in the United Kingdom and Israel. The first case of LPDV in the United States was found in 2009 in Arkansas. This study tests different reservoirs for the virus. DNA was extracted from samples of different origins and preservation types. Through PCR and gel electrophoresis analysis, different sample types from turkey populations were tested for LPDV. This study provides a method for submitting blood …

Investigation Of Origin And Growth Of Fungi In Coastal Beach Sand, Ruth L. Wright

Honors Theses

In a previous study from this lab (Stevens, Evans, & Aguirre, 2012) yeast colonies were isolated and grown grown from sand collection at pristine, medium use and high use beaches along the grand strand. In that study greater yeast abundance and greater diversity both correlated with higher census of human use, suggesting that some yeast growth of sites was anthropogenic. However the sand matrix itself also varied from very fine, uniform, dark sand at the pristine beach to coarser, color varying, less tightly packed sand at residential and commercial beaches. This suggested an alternative hypothesis to differential colonization and growth …

Effects Of The Pathogen Mycoplasma Gallisepticum Transmission On Growth And Condition Of Eastern Bluebirds Nestlings (Sialia Sialis), Gurshan Kaur

Honors Theses

A critical aspect to understanding disease dynamics is to understand how transmission occurs between hosts. There are two basic modes of transmission: vertical and horizontal. Vertical transmission is the passage of a pathogen from mother to offspring before or during birth, whereas horizontal transmission occurs between an infected host to a susceptible host. Mycoplasma gallisepticum (MG) is a common bacterial pathogen of poultry that causes respiratory disease. Infection of MG often results in weight loss, slowed growth rate, and increased mortality. Both vertical and horizontal transmission of MG have been found to occur in poultry. In the mid-90s, MG underwent …

Screening For Mental Health Concerns Across Pregnancy : Factors Associated With Depression And Anxiety Symptons In A Large Obgyn Clinic, Addie Keller

Honors Theses

Depression and anxiety are prevalent among pregnant women, however, mental health continues to be a portion of care neglected in the obstetric setting. Depression is of-ten thought of as a disorder that leads to a persistent feeling of sadness. Anxiety is charac-terized by excessive fear and worry. Because of the many changes occurring throughout pregnancy, both physically and emotionally, it is not uncommon for pregnant women to struggle with depression, anxiety, or both. Previous studies have found that there are many factors associated with depression and anxiety throughout pregnancy. This study focuses on the relationship between age, gravida, and social …

Histone Deacetylase Inhibitors And Breast Cancer Metastasis: A Review And Exploration Of Hdac(I)S And Other Chemotherapeutic Agents, William E. Sistrunk

Honors Theses

The traditional perspective of Histone Deacetylase enzymes is focused on their inherent epigenetic modification characteristics. While it is true that the histone modification these enzymes exhibit play a role in cancer and related diseases, Histone Deacetylase has a variety of non-histone targets. The non-histone targets include microtubules and are of specific interest because of the microtubules’ role in cell line differentiation, replication, apoptosis, and cancer metastasis. Using a variety of Histone Deacetylase Inhibitors (HDACi) and other chemotherapeutic compounds, our research group explored the HDACi effect on breast cancer cell lines. Our goal was to indicate the presence of HDACi cell-line …

Effects Of Mycoplasma Gallisepticum On Experimentally Infected Eastern Bluebirds (Sialia Sialis), Meredith A. Fry

Honors Theses

The bacterium Mycoplasma gallisepticum is an avian respiratory pathogen that causes inflammation and swelling of conjunctiva in domestic poultry and wild finches. In the past, severity of conjunctivitis symptoms has been used to quantify infection severity and host resistance. However, many songbirds function as hosts to M. gallisepticum but do not develop this symptom at all. The absence of conjunctivitis, as well as other clinical signs, hinders our understanding of M. gallisepticum infection in the songbird community because some species are responding very differently than others. One such species is the Eastern Bluebird (Sialia sialis), a common songbird of the …

O-Glcnacylation Of Hif-1Α Protein In Human Breast Cancer Cells, Joshua D. Dolsen

Honors Theses

Cancer is an insidious disease that, if not caught in time, can cause devastating effects on the human body, especially if it metastasizes. It is important to note that each cancer behaves and develops differently based on its location in the body and the cellular characteristics constitute the instance of the disease. However, the development of cancer can universally be characterized by the acquisition of different hallmark abilities that promote disease progression. Proteins known as hypoxia-inducible factors (HIFs) can influence progression through these hallmarks, but primarily provides cancer cells with the ability to alter its metabolism to survive and further …

Neuroprotection With Novel Anti-Oxidant And Cannabinoid-Based Small Molecules, Jacqueline R. Mcgrath

Honors Theses

Neurodegenerative diseases are caused by various underlying mechanisms within the nervous system. Excitotoxicity is a hallmark of many neurodegenerative diseases, and is produced by over excitation of glutamate receptors on neurons, ultimately leading to cell death. Protein aggregates and oxidative stress have also induced neuronal cell death that lead to many neurodegenerative diseases as well. Many compounds isolated from plants have shown protective ability against these underlying toxicity mechanisms. In this study, we tested several cannabinoid and anthyocanin-based small molecules protective abilities against excitotoxicity. We found several compounds that protected against glutamate-induced excitotoxicity in a concentration-dependent manner. We also tested …

The Upright Go Wearable Posture Device: An Evaluation Of Postural Health, Improvement Of Posture, And Salivary Cortisol Fluctuations In College Students, Alexandra Lauren Elliott

Honors Theses

Health professionals consider improper posture as a risk factor for musculoskeletal disorders, chronic pain, and additional health issues. The chief aim of my study was to investigate links between poor posture and health, particularly in college students. To collect data regarding postural health, I distributed an exploratory survey to Human Anatomy and Physiology II (BISC 207) students at the University of Mississippi in Spring 2018. Students reported significant concern with quality of personal posture and significant experience with negative side effects of poor posture. Results demonstrated a need for postural education, leading to phase 2 of my experiment, the evaluation …

Bacteria In Salt Pans Along The Mississippi Gulf Coast, Lauren A. Lawson

Honors Theses

Salt pans form in shallow depressions in the ground where salt water evaporates leaving a hypersaline environment remaining. These pans become flooded during extremely high tides and as time progresses, this additional salt water is evaporated leaving behind more salt deposits. Marine salt pans can provide habitat for halophilic microorganisms and provide an interesting environment for study as conditions can change with both sediment and water depth. Towards the surface of sediment in salt pans, oxygen is still available, however, deeper sediments have limited oxygen availability and are likely anaerobic. Deeper sediments can also have higher salt concentrations so may …

Interactions Of Fentanyl With Gp120 In The Central Nervous System, Meagan Buchanan

Honors Theses

The Human Immunodeficiency Virus (HIV) has affected more than 75 million individuals worldwide. HIV not only affects the peripheral system through the targeting of T cells, but also causes adverse effects in the central nervous system. Individuals suffering from HIV often experience neuropathic pain and are prescribed opioids to combat the chronic pain. Along with the increase of opioids prescribed to HIV patients, the number of deaths related to the synthetic opioid, fentanyl, has increased drastically. Drug abuse and HIV are interlinked epidemics; individuals who are HIV positive and referred to as “NeuroAIDS.” The HIV envelope protein, gp120, has been …

The Incorporation Of Lipids Into The Cellular Membrane Of Salmonella, Betsy H. Redfern

Honors Theses

Salmonella is a gram negative, facultative anaerobic food borne pathogen and is the leading cause of deaths related to food borne illnesses. In order to establish an infection successfully, Salmonella must be able to survive in the presence of various stressors that it encounters, namely changes in pH, oxygen availability, osmolarity and bile. Previous research has shown that exposure to bile causes a shift in fatty acid composition in the cell membrane of the enteric bacterium Enterococcus faecalis. Thus, this led to the hypothesis that Salmonella incorporates fatty acids into its cellular membrane following exposure to bile and thereby protects …

Deducing The Reproductive, Behavioral, And Learning Effects Of Developmental Cannabinoid Exposure In Zebrafish, Marisa L. Kutchma

Honors Theses

With the spreading legalization of marijuana, it is important to investigate the effects of two of its active ingredients—Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD). THC and CBD differ in that THC exerts psychoactive effects, while CBD does not. Thus, CBD is renowned for its analgesic effects in treating a variety of ailments, for example, childhood drug-resistant epilepsy. In addition, there is an increase in reports of prenatal CBD usage. As it is increasingly used, research has fallen far behind the proliferation of CBD and more needs to be done, particularly in the developmental realm. This study utilizes a developmental origins of …

The Meaning Of Song Type: Exploring Behavioral Responses Of Field Sparrows To Three Simple Song Types, Eliza Foli

Honors Theses

The frequency, rate, and overall quality of a male’s song may indicate the singer’s physical quality, either as a threat or as a potential mate, and are used for species recognition. However, the degree to which a song must differ acoustically to communicate different information about the singer remains unclear. Analysis of male field sparrow simple song recorded in southwest Michigan revealed three structurally distinct clusters of simple song that differ in frequency characteristics. We hypothesize that songs in each cluster convey information about the singer and that receivers respond more strongly to songs more similar to their own song. …

Time Course Effects Of Repetitive Social Defeat Stress On A Prefrontal Cortex-Dependent Cognitive Flexibility Task, Shaffer Hannah

Honors Theses

Stress is known to change the structure and function of the brain in animals and humans as well as their behavior. It has a high correlation with the development of psychiatric disorders as well. We looked to investigate how repetitive intermittent social defeat stress using the resident-intruder paradigm in rats affected a cognitive flexibility task. The task used was a set-shifting protocol known to be associated with the function of the prefrontal cortex. Measurements on the task were taken intermittently between social stress sessions to determine short-term effects and 10 days after the last social stress session to measure long …

Isolation And Characterization Of A Novel Terpenoid From The Needles Of Eastern White Pine (Pinus Strobus), And Its Potential Relation To Climate Change, Samantha Hack

Honors Theses

Climate changes is one of the most serious threats facing the future of our planet, and with is we will see drastic changes to water levels global temperatures, and atmospheric conditions. Modeling future atmospheric conditions is crucial if we are to plan for and mitigate the consequences of climate change – while important, these models will not be useful to future scientists unless various parameters, such as BVOC emission to the atmosphere, are accounted for and included in computer models. Eastern white pine (Pinus strobus) are predicted to be a major component of future climax forests as their abundance increases …

The Correlation Between The Microbiome And Neurodegenerative Disorders Such As Alzheimer Disease, Aurora Mokris

Honors Theses

Recent studies suggest that there are 1.3 times as many microbial cells as human cells in the body (Abbot, 2016). Another study claims that the combined genomes of this microbiota is 150 times that of the human genome (Zhuang & Shen, 2018). If you have ever had the feeling that you are not alone in an empty room you are most certainly correct. Your body is teeming with millions of organisms living in mutualistic symbiosis with you and surrounding microbes, but at times, this seemingly harmonious relationship can be disturbed, resulting in serious physical and psychological changes to the human …

Resting State Fmri Study Of The Olfactory Region In Autism, Madlyn Lawrence

Honors Theses

This thesis was conducted to further the investigation of the Olfactory system of a typically developing individual compared to an individual with Autism. The Olfactory system is unique in that it is the only sensory system that is not relayed through the thalamus in the brain. Autism Spectrum Disorder (ASD), also known as Autism, is a developmental disorder which impairs a person's social, behavioral, developmental, cognitive and psychological aspects. Autism Spectrum Disorder can present with symptoms such as difficulty communicating, difficulty with social interactions obsessive thoughts and compulsions and repetitive behaviors. Subjects with Autism Spectrum Disorder present with an inability …

The Effects Of Climate Change And Forest Disturbances On Terpene Production Of White Pine (Pinus Strobus) And Red Pine (Pinus Resinosa) In Northern Michigan, Troy Dehagen

Honors Theses

The secondary impacts that climate change may have on the interactions between forests and the atmosphere through forest disturbances is of increasing interest as the climate continues to change. Anthropogenic climate change, which is a direct result of coal and fossil fuel emissions, is likely to impact forest ecology through increased temperatures and extreme precipitation events, thus increasing the frequency and severity of climate-induced forest disturbances. Forest disturbances may have a secondary impact on the production and emission of biogenic volatile organic compounds (BVOC) within forests. In the presence of oxides of nitrogen (NO_x) produced from fossil fuel …

Effects Of Age And Exercise On Density Of Sympathetic Innervation And Localization With Nerve Growth Factor And Glial Cell Line-Derived Neurotrophic Factor In Vascular Tissue, Kori Mecklenburg

Honors Theses

Hypertension is a condition that affects nearly 75 million people in the United States (Merai et al, 2017). To better understand this mostly idiopathic condition, the role of survival factors on arterial innervation must be understood. Nerve growth factor (NGF) and glial cell-line derived neurotrophic factor (GDNF) have been shown to support development and maintenance of the sympathetic nervous system. The aim of this study was to reveal how density of sympathetic innervation changes in mesenteric arteries over time and with six-months of exercise. Additionally, this study aimed to reveal the localization of GDNF and NGF alongside these changes in …

The Impact Of Male-Exposure In The Neuronal Response Of The L3 Auditory Intemeuron To Model Calls, Shekinah Dosunmu

Honors Theses

The L3 auditory neuron in female cricket Acheta domesticus responds to phonotactically attractive calls with decrement: a reduction in the number of action potentials in response to consecutive sound pulses within a chirp. Such unique response has been reported only in virgin females. This study evaluates the response of the L3 in male-exposed females to determine whether they respond to auditory stimuli differently from those exhibited by virgin female crickets.

Preliminary data indicate that L3 in young exposed female crickets responds with different decrement patterns as those reported for virgin females. The implications of these findings are discussed.

Neuronal And Behavioral Response Relationships In Virgin Females Of Acheta Domesticus, Brandon Shin

Honors Theses

Animals that communicate acoustically serve as models for investigating how organisms respond to sound. For instance, in field crickets, females exhibit phonotaxis (directed movement towards the sound's source) to calls with a specific frequency, intensity, and syllable period (SP) - the time between the beginning of one sound pulse and the beginning of another within the same chirp. Additionally, auditory neurons in females produce action potentials in direct response to the sound pulses of a male 's call. A previous study on the species Gryllus bimaculatus demonstrated a relationship between an individual female's behavioral and neuronal responses; however, no such …

Global And Gene-Specific Regulation In Freeze-Tolerant Anuran Dryophytes Chrysoscelis, Elizabeth Claire Sinnathamby

Honors Theses

Cope’s Gray Treefrog, Dryophytes chysoscelis, seasonally tolerates freezing. During this process, it is subject to cellular stress from factors such as metabolic starvation, DNA damage, toxin accumulation (from cellular metabolism), and the risk of protein misfolding. Preliminary transcriptome data indicates that many mRNA transcripts vary in relative abundance within hepatocytes of D. chrysoscelis during discrete periods of warm acclimation, cold acclimation, freezing, and thawing. Physiological changes that occur in this frog are likely the result of epigenetic regulation—an alteration in gene expression that does not influence DNA sequence. This modification in gene expression can be observed by the subsequent change …

The Effects Of Sublethal Antibiotics On Listeria Monocytogenes, Marlena Rae Merling

Honors Theses

Antibiotics can be found in sublethal levels environmentally as pollution and within the body when used as medication. Antibiotics induce stress responses and sometimes act as signaling molecules in bacteria. In order to better understand the relationship between antibiotics and bacterial infections, the effects of sublethal antibiotic exposure on the ability of Listeria monocytogenes to infect macrophages was studied. Listeria monocytogenes is an intracellular pathogen of the gastrointestinal tract that is facultatively anaerobic. Two strains of Listeria monocytogenes were tested: a lab strain and a clinical cardiotropic strain. The strains were grown in liquid media overnight aerobically or anaerobically with …