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University of Arkansas, Fayetteville

Biological Sciences Undergraduate Honors Theses

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Mate Guarding Against Strong Men Displaying Affiliative And Aggressive Humor, Jacob Pauley May 2024

Mate Guarding Against Strong Men Displaying Affiliative And Aggressive Humor, Jacob Pauley

Biological Sciences Undergraduate Honors Theses

Mate retention behaviors serve to discourage partner defection from a current pairbond. Such behaviors are oftentimes more prevalent toward intrasexual rivals exhibiting physical and behavioral cues implicating that rival as an optimal mate. Among these features in men are their upper body strength, a feature diagnostic of heritable fitness, and men's ability to produce humor, a cue to their social competence. This study considered the intersection of these desirable features in shaping men's mate retention behavior toward an intrasexual rival. After learning of a hypothetical interloper exhibiting high or low upper body strength while similarly using humor in an affiliative …


Establishing An Objective, Quantifiable Method For Detecting Erosive Tooth Wear, Camille Kita May 2024

Establishing An Objective, Quantifiable Method For Detecting Erosive Tooth Wear, Camille Kita

Biological Sciences Undergraduate Honors Theses

This study aims to monitor and evaluate erosive tooth wear (ETW) by measurement of enamel surface thickness and texture in a clinical setting. The objective approach is fundamentally different from the standard subjective visual assessment that professionals in the dental field using the Basic Erosive Wear Evaluation (BEWE) method.

Twenty-nine hyposalivation and three control subjects were used in this longitudinal study, for a total of 597 samples (only 577 teeth were eligible for surface texture analysis) evaluated in a longitudinal study including both baseline and 12 month follow up surfaces. Each participant’s buccal surface of the tooth was first analyzed …


Towards Understanding The Function Of An Ets-Like Gene In Nematostella Vectensis: Generation Of A Knockout Mutant Line And A Transgenic Reporter Line, Emily Bullock May 2024

Towards Understanding The Function Of An Ets-Like Gene In Nematostella Vectensis: Generation Of A Knockout Mutant Line And A Transgenic Reporter Line, Emily Bullock

Biological Sciences Undergraduate Honors Theses

Due to their unique phylogenic position as sister to Bilateria, Cnidaria are often credited with the utility of allowing for reconstruction of ancestral biology based on characteristics shared with bilaterians and other animals. This factor makes investigation into the nervous systems of cnidarians critical in understanding early neural evolution. Wamides, a class of neuropeptides, have been shown to play a regulatory role in life cycle transitions across many different species. The cnidarian specific Wamide neuropeptide, GLWamide, has previously been identified to play an accelerator role in the metamorphic timing of a specific species of sea anemone, Nematostella vectensis. However, …


Effect Of Progesterone On Cognition Among College Aged Women, Katelyn Helberg May 2024

Effect Of Progesterone On Cognition Among College Aged Women, Katelyn Helberg

Biological Sciences Undergraduate Honors Theses

Women who have a reoccurring menstrual cycle and do not take hormonal birth control naturally experience changes in the amount of sex hormones that their body produces. These sex hormones help promote sexual development, fertility, and mood regulation, but can be hard to study due to their conflicting effects on each other. One such hormone, progesterone, is produced in different concentrations throughout the menstrual cycle to prepare the uterus for a potential pregnancy. However, it also may have secondhand effects on how well women can complete everyday tasks involving memory, attention, processing speed, and more which is what we measured …


The Effect Of Hormonal Contraceptive Use On Dominance And Prestige Tactics, Carson Chappell May 2024

The Effect Of Hormonal Contraceptive Use On Dominance And Prestige Tactics, Carson Chappell

Biological Sciences Undergraduate Honors Theses

This study was designed to investigate the relationship between hormonal contraceptives and prestige and dominance status-seeking tactics. Existing literature has examined how the hormones estrogen and progesterone, especially in relation to the fertile window of the menstrual cycle, are associated with prestige and dominance but has yet to look in depth at how hormonal contraceptives might alter this impact. The current study asked participants to complete a 22- item questionnaire assessing dominance and prestige. I hypothesized that women on hormonal contraceptives would have lower scores for prestige and dominance compared to women who are naturally cycling. The results did not …


Survival Of Methanogens Desiccated On Mars Soil Simulants: Implications For Life On Mars, Lanee Knight May 2024

Survival Of Methanogens Desiccated On Mars Soil Simulants: Implications For Life On Mars, Lanee Knight

Biological Sciences Undergraduate Honors Theses

Because of Mars’s chemical features, it can be studied in the search for life and is a significant figure in the study of astrobiology (McKay, 2010). Dr. Kral’s laboratory studies methanogens, microorganisms in the domain Archaea, as possible life forms on Mars. Since some methanogens can withstand harsh environmental conditions and emit methane as a waste product, the growth of these microorganisms can be used as an indicator of potential life in the Mars subsurface (Kral et al., 1998). In this research, four methanogens, Methanothermobacter wolfeii, Methanobacterium formicicum, Methanosarcina barkeri, and Methanococcus maripaludi were desiccated in the …


Characterization Of Mitochondrial Morphology In Drosophila: Early Embryogenesis Description Via Confocal Microscopy, Kendall Miller May 2024

Characterization Of Mitochondrial Morphology In Drosophila: Early Embryogenesis Description Via Confocal Microscopy, Kendall Miller

Biological Sciences Undergraduate Honors Theses

Mitochondria are not static organelles, but instead are dynamic networks that undergo rapid changes in subcellular distribution, organization, and activity in response to external stimuli. Notably, mitochondria can undergo fission and fusion, collectively known as mitochondrial dynamics. Mitochondrial fusion creates assembled networks of mitochondria that are maximally efficient at generating ATP through oxidative phosphorylation. Conversely, mitochondrial fission leads to network fragmentation and a shift towards glycolysis, which is the dominant mode of ATP generation in oxygen-limiting and stressed conditions. While mitochondrial dynamics have been intensively studied in isolated cells under stressful conditions, much less is known about how mitochondria behave …


Do Heat Waves Drive Natural Selection In Damselflies?, Adam Baranyk May 2024

Do Heat Waves Drive Natural Selection In Damselflies?, Adam Baranyk

Biological Sciences Undergraduate Honors Theses

Climate change has led to changes in both mean temperatures and temperature extremes over the recent years. These changes have had differential effects on animals throughout the world. Ectotherms depend on their external environment for thermal regulation, making them especially susceptible to temperature extremes. It is not yet clear whether there is a relationship between physical traits in ectotherms, and survivorship throughout a heat wave. That is, whether or not temperature extremes driven survival selection. In this study, a heat wave was simulated artificially using thermally regulated mesocosms at different temperatures (18°C, 22° C, 26° C, 30° C) with a …


A Meta-Analysis For Laboratory Diagnostics For Coccidioidomycosis, Mary C. Cowen May 2024

A Meta-Analysis For Laboratory Diagnostics For Coccidioidomycosis, Mary C. Cowen

Biological Sciences Undergraduate Honors Theses

Coccidioidomycosis, commonly referred to as Valley Fever, is a fungal infection found in arid regions of the southwestern United States and Mexico. Infection occurs through inhalation of airborne spores from Coccidioides species, Coccidioides immitis and/or Coccidioides posadasii, and proceeds in both pulmonary and disseminated fashions. Approximately 60% of patients with coccidioidomycosis remain asymptomatic, while 40% will experience symptoms. Within the literature, there are no papers that summarize sensitivity and specificity values between different tests; therefore, this paper presents sensitivity and specificity results across different tests and companies (Meridian, IMMY, and MiraVista).


Growth Of Methanogens On Kaolinite, A Clay That Has Been Identified On Mars, Hailey Littrell May 2024

Growth Of Methanogens On Kaolinite, A Clay That Has Been Identified On Mars, Hailey Littrell

Biological Sciences Undergraduate Honors Theses

Methanogens have been studied as a model for life on Mars for 28 years now in the Kral lab. The discovery of methane in the Martian atmosphere by ground-based and orbital observations as well as Curiosity Rover (Formisano, V. et al., Krasnopolsky, V.A. et al., Mumma, M.J. et al.) has added relevance to these types of studies. Methanogens were chosen due to their ability to live in harsh environments, very similar to the Martian terrain. In addition to methane in the atmosphere, phyllosilicate clays have also been identified. One of those clays is kaolinite. Kaolinite has been found to not …


Exploring Genomic Convergence For Adaptations To Freezing Environments In Polar Fish, Ethan Talley May 2024

Exploring Genomic Convergence For Adaptations To Freezing Environments In Polar Fish, Ethan Talley

Biological Sciences Undergraduate Honors Theses

Convergent evolution provides valuable insights into how natural selection shapes species traits. Genomic analysis of lineages that display convergent traits has the potential to identify candidate genes for environmental adaptations across the scope of entire genomes. One remarkable example of convergent evolution is the independent development of antifreeze proteins (AFPs) in phylogenetically distant polar fish lineages. While AFPs themselves are relatively well studied, the full genomic context of adaptation to freezing conditions in these fish lineages remains largely unexplored. Leveraging the whole genome sequences previously assembled in our lab, along with other high-quality genomes available in GenBank, I examined the …


Studying The Stability Of Collagen/Heparin Coatings To Be Used In Cell Therapy Applications, Gavin Mussino Aug 2023

Studying The Stability Of Collagen/Heparin Coatings To Be Used In Cell Therapy Applications, Gavin Mussino

Biological Sciences Undergraduate Honors Theses

This honors thesis aims to investigate the reusability and performance of cell coatings for cell therapy applications. Cell therapy, which involves the use of human cells to repair or replace damaged tissues, holds immense potential for medical advancements. However, ensuring the survival and functionality of transplanted cells remains a significant challenge. We focused on studying the effectiveness of coatings applied to cells for improved cell growth and viability. The research project involved the preparation of the coatings using a layer-by-layer method and the subsequent seeding of cells. The coated cells were then subjected to a series of experiments to assess …


The Effects Of Salt And Temperature On Three Methanogen Species: Implications For Mars, Katy Dunlap May 2023

The Effects Of Salt And Temperature On Three Methanogen Species: Implications For Mars, Katy Dunlap

Biological Sciences Undergraduate Honors Theses

The question of whether life has ever existed on Mars – either in the past or currently – has been pursued for decades. This debate has been prompted by a variety of discoveries regarding similarities between Mars and Earth and more recently concerns over human extinction. Mars, like Earth, once had large amounts of water, a key ingredient for life. H2O exists on Mars in various forms now, and it is theorized that there is liquid water beneath the surface as well. Mars also contains salt and is very cold at its surface, pointing researchers towards the idea …


Optimum Time To Add The Feed Additive Availa-Zmc To Reduce The Incidence Of Bacterial Chondronecrosis With Osteomyelitis Lameness In Broiler Chickens, Ashley Ault May 2023

Optimum Time To Add The Feed Additive Availa-Zmc To Reduce The Incidence Of Bacterial Chondronecrosis With Osteomyelitis Lameness In Broiler Chickens, Ashley Ault

Biological Sciences Undergraduate Honors Theses

Lameness is a health condition threatening the welfare of broiler chickens in the poultry industry. It can be caused by a bacterial infection called Bacterial Chondronecrosis with Osteomyelitis (BCO). Zinpro has created Avalia-ZMC, a feed additive that has been proven to reduce lameness by 20% in wire-flooring pens and 25% in litter-flooring pens (Alrubaye et al., 2020). This experiment focuses on the optimal time to add Availa-ZMC to the diet of the broiler chickens to help reduce the incidence of lameness. This trial took 56 days with 26 pens at the University of Arkansas Poultry Research Farm. At the start …


Minimal Carbon Requirements For Potential Colonizers Of Other Planets, Benjamin Tan May 2023

Minimal Carbon Requirements For Potential Colonizers Of Other Planets, Benjamin Tan

Biological Sciences Undergraduate Honors Theses

The NASA Office of Planetary Protection regulates the safe scientific exploration of other planets. Specifically, the office enacts rules to discourage interplanetary mission practices that would lead to the contamination of Earth-originating microbial life on other planets. Interplanetary contamination jeopardizes the potential to obtain reliable scientific evidence for extraterrestrial life. In coordination with this office, the biosignatures of potential colonizers of other celestials bodies are studied. Several organisms of Earth qualify as potential colonizers of other planets.

This experiment focused on the environment of Mars in particular. Two organisms were tested: Desulfovibrio arcticus and Desulfotalea psychrophila. Both are psychrotolerant or …


Sequence Analysis Of Herbicide Target Genes In Herbicide-Tolerant Rice, Jonathan Kearney, Nilda R. Burgos, Gulab D. Rangani May 2023

Sequence Analysis Of Herbicide Target Genes In Herbicide-Tolerant Rice, Jonathan Kearney, Nilda R. Burgos, Gulab D. Rangani

Biological Sciences Undergraduate Honors Theses

The tolerance of mutagenized rice (Oryza sativa) lines to selector herbicides was investigated and the sequence of ALS gene was analyzed in plants that survived treatment with 4x the label rate of imazethapyr herbicide. This was done to determine if insensitivity to imazethapyr is due to mutation(s) in the herbicide binding site. Seedlots previously treated with ethyl-methyl sulfonate were planted in the field and 3-leaf seedlings were treated with various herbicides to screen for herbicide-tolerant mutants. Seeds from survivors composed the rice lines tested in the current research. Seeds were planted in the greenhouse and 3-leaf seedlings were …


Effects Of Maternal Disease History On Provisioning, Brooding, And Offspring Outcomes, Sakura Roberts May 2023

Effects Of Maternal Disease History On Provisioning, Brooding, And Offspring Outcomes, Sakura Roberts

Biological Sciences Undergraduate Honors Theses

Disease within a population has the ability to shape the development, evolution, and general performance of a species. Pathogen exposure to hosts can influence their physiology and behavioral patterns to further shape offspring immunity. Parental conditions experienced by offspring during early development can benefit survival and fitness (e.g. increasing provisioning rates), as well as help deter against similar diseases experienced by parents. By testing if parental behavior changes can better prepare offspring outcomes for disease exposure, such as disease severity or duration of infection, we can see the beneficial impacts it has on disease dynamics and host-pathogen processes. Incubation temperature, …


Molar Macrowear As A Proxy For Age In A Captive Sample Of Papio Hamadryas, Lauren Conrad May 2023

Molar Macrowear As A Proxy For Age In A Captive Sample Of Papio Hamadryas, Lauren Conrad

Biological Sciences Undergraduate Honors Theses

This study is methods-focused, centering around molar crown macrowear and its performance as a proxy for age in a sample of pedigreed, non-human primates. It analyzes the correlation between age-structured variables and molar wear among both males and females in a captive group of baboons. Here, I examined whether wear is significantly correlated with age-related variables (i.e., generations/cohorts) and whether the structure of the “age” dataset differed across wear categories. Because chronological age is unknown, I used documented pedigrees and parent-offspring relationships to group individuals into possible generations. I then used dental development charts to group individuals into cohorts based …


Early Life Stress Predicts Future Conduct Disorder In Adolescents, Savannah Ellis May 2023

Early Life Stress Predicts Future Conduct Disorder In Adolescents, Savannah Ellis

Biological Sciences Undergraduate Honors Theses

Early Life Stress (ELS) and adversity increase people’s risk for developing mental, social, or emotional dysregulation and disorders later in life. The objective of this study was to test whether ELS in adolescents could prospectively predict future conduct disorder. The study additionally tested potential neural mediators of the effect of ELS on future conduct disorder, and specifically targeted the structural connections from the anterior insula and medial prefrontal cortex to the Nucleus Accumbens (NAcc). Data for the project came from the Adolescent Brain Cognitive Development Study (ABCD study), which is a longitudinal multi-site consortium funded by the National Institutes of …


Effects Of Sow Vocalization And Scent On Complete Blood Cell Count During Early Weaning Period, Mason Paladino May 2023

Effects Of Sow Vocalization And Scent On Complete Blood Cell Count During Early Weaning Period, Mason Paladino

Biological Sciences Undergraduate Honors Theses

Piglets are deprived of their sows’ touch, sound, and smell after weaning which results in biological stress. The present study investigated continuing exposure of sow vocalization and scent during the early weaning period on complete blood cell count. A total of 12 litters, 8 piglets (4 male and 4 female) per litter were selected at weaning and assigned to 1 of 4 experimental treatments: control, O (olfactory group with scent and no vocal stimulation), V (non-olfactory with vocal stimulation), VO (vocal stimulation and olfactory stimulation) as a 2x2 factorial arrangement. Vocal stimulation was emulated by an audio recording of the …


Measuring Energy Demands Of Dynamic Remodeling Events During Embryogenesis In Live Drosophila Embryos, Grayson Young May 2023

Measuring Energy Demands Of Dynamic Remodeling Events During Embryogenesis In Live Drosophila Embryos, Grayson Young

Biological Sciences Undergraduate Honors Theses

Embryonic development is a complex process requiring dynamic cell movements to create complex tissue structures. We assume that these embryonic dynamic remodeling events are highly energy intensive and that this energy expenditure is mediated by mitochondria. However, this has been difficult to demonstrate in live embryos. Convergent extension of the Drosophila neuroectoderm is a promising system to study the bioenergetics of tissue remodeling because it changes from a static to a dynamically remodeling tissue with temporal precision. We hypothesize that the switch from static to dynamic development at the onset of convergent extension will be accompanied by an increase in …


An Overview Of Serial Depletions Of Global Marine Fisheries 1950 To 2019, Alison Follmer May 2023

An Overview Of Serial Depletions Of Global Marine Fisheries 1950 To 2019, Alison Follmer

Biological Sciences Undergraduate Honors Theses

Overfishing is a global issue that poses a significant risk to the entire ocean ecosystem in diminishing biodiversity and ecosystem function. This thesis examined the pattern and pace of fisheries depletions due to commercial fishing during the past 70 years. The Food and Agriculture Organization of the United Nations (FAO) Division of Fisheries and Aquaculture maintains a database of global hauls of marine taxa (reported in metric tonnes) from 1950 – 2019. These data were queried to determine the total number and sequence of fisheries depletions documented by the historic record. Analysis of this database showed progressive, linearly-increasing exploitation of …


Effect Of Soy Co-Products In Supplements For Grazing Cattle On Growth, Complete Blood Cell Counts, And Physiological Response Following A Lipopolysaccharide Challenge, Bralee Lansdell May 2023

Effect Of Soy Co-Products In Supplements For Grazing Cattle On Growth, Complete Blood Cell Counts, And Physiological Response Following A Lipopolysaccharide Challenge, Bralee Lansdell

Biological Sciences Undergraduate Honors Theses

The objective of this study was to determine the effect of soy co-products (soybean meal and soy oil) in the diet on the growth and hemocytology of cattle during a 56-day growing phase and the physiological/behavioral response to an endotoxin challenge. Angus crossbred steers (n = 36; 289 ± 31 kg, initial body weight ± SD) were stratified by body weight and sire; and assigned randomly to pastures (n = 9; 0.45 ha/mixed-grass pasture). Pastures were assigned randomly to 1 of 3 dietary treatments: 1) a control supplement containing no soy co-products, 2) a supplement containing soybean meal, or 3) …


Development Of A Computational Model To Investigate Pathways And The Effects Of Treatment In Fanconi Anemia, Sabrina Kellett May 2023

Development Of A Computational Model To Investigate Pathways And The Effects Of Treatment In Fanconi Anemia, Sabrina Kellett

Biological Sciences Undergraduate Honors Theses

Fanconi Anemia (FA) is a rare type of anemia that is not easily studied and can have very detrimental effects. This disease compromises the bone marrow, resulting in decreased hemopoiesis. Symptoms of FA also include abnormalities in the brain and spinal cord, incorrect formation of the kidneys, abnormal formation of the heart and lungs, and a dramatically increased risk of developing cancer. FA can be caused by various mutations in any of the 22 genes that encode for proteins involved in what is called the FA DNA repair pathway. In healthy individuals, this pathway specifically repairs interstrand cross-links (ICLs) recognized …


Exploring A Potential Bias In Detection Of Mesopredators By Cameras, Rylee Gibson May 2023

Exploring A Potential Bias In Detection Of Mesopredators By Cameras, Rylee Gibson

Biological Sciences Undergraduate Honors Theses

Mesopredators, such as the raccoon (Procyon locor), Virginia opossum (Didpelphis virginiana), and striped skunk (Mephitis mephitis) play crucial ecological roles as predators, prey, and disease vectors across much of the United States. Because of their importance and the way that populations of these mesopredators can dramatically increase due to human-subsidized resources, it is imperative that studies attempting to quantify mesopredator community composition are accurate and unbiased. However, it has recently been suggested that not all mammals trigger motion-activated wildlife game cameras at the same rate and for some species detection probability may be biased. My goals for this thesis were …


Computational Modeling Of The Fanconi Anemia Gene Network And Its Connection To Cancer, Alyssa Warren-Belford May 2023

Computational Modeling Of The Fanconi Anemia Gene Network And Its Connection To Cancer, Alyssa Warren-Belford

Biological Sciences Undergraduate Honors Theses

Fanconi anemia (FA) is a rare genetic condition in which the cell’s DNA repair machinery is dysregulated, significantly increasing the chances of tumorigenesis. Further research is being done in order to improve patient outcomes and incidences of cancer. Our group created a computational model of the FA DNA repair gene network, which removes interstrand crosslinks found in damaged DNA and repairs it so DNA synthesis can continue. Computer simulations show the number of DNA damage indicators decreased as the pathway continued. This was expected as the FA pathway repairs DNA damage. The goal of this project was to provide further …


Sex Differences In Host Resistance And Tolerance To The Common Avian Pathogen Mycoplasma Gallisepticum, Chloe Connelly May 2023

Sex Differences In Host Resistance And Tolerance To The Common Avian Pathogen Mycoplasma Gallisepticum, Chloe Connelly

Biological Sciences Undergraduate Honors Theses

As we face the threat of global pandemics, one thing becomes clear: biological research is not just about the pursuit of the unknown, but about protecting our future. Understanding disease transmission and predicting pathogen epidemics is more important than ever. Prior studies have indicated that in populations where one sex engages in more social behaviors and movement that sex may drive disease transmission. This supports sex as a factor to consider in the study of epidemic dynamics. Host physiology and immune strategies are another factor that can influence epidemics. Two commonly examined strategies are tolerance and resistance. Tolerance is the …


Involvement Of Chromosome Remodeling Complexes On Chromosome Segregation, Adelle Warford May 2023

Involvement Of Chromosome Remodeling Complexes On Chromosome Segregation, Adelle Warford

Biological Sciences Undergraduate Honors Theses

Errors in chromosome segregation during cell replication are detrimental to the health of living cells. These errors cause aneuploidy: daughter cells with an incorrect number of chromosomes, as well as polyploidy: the complete duplication of a genome. In humans, these segregation errors are responsible for many harmful diseases and disorders. Using the model organism S. cerevisiae, a double mutant was created by removing two key chromosome remodeling complexes, SWR1 and INO80, both known to independently cause aneuploidy, decreased fitness, and damages the sensitivity of a cell's DNA (Andalis et al. 2004). By creating a double mutant strain, genetic cell …


A Structural Examination Of The Connection Between The Amygdala And Nucleus Accumbens In Adolescents With Clinical Anxiety, Alyssa Griffith Dec 2022

A Structural Examination Of The Connection Between The Amygdala And Nucleus Accumbens In Adolescents With Clinical Anxiety, Alyssa Griffith

Biological Sciences Undergraduate Honors Theses

The prominence of anxiety disorders in today’s general population is a major public health concern. Advancing research of the underlying pathophysiology of anxiety disorders can lead to the discovery of effective treatment interventions to treat the mental and physical symptoms of anxiety, and thus improve quality of life. This study aimed to examine two brain areas in the limbic and reward systems, the amygdala and Nucleus Accumbens (NAcc), and the structural white matter connection between them. This neural circuit assigns affective valence to environmental stimuli and motivates behavior to avoid potential harm. This study utilized diffusion Magnetic Resonance Imaging (dMRI) …


Survey For Usage Of And Interest In Personalized Nutrition As A Possible Health Approach, Kimberly Garrett Dec 2022

Survey For Usage Of And Interest In Personalized Nutrition As A Possible Health Approach, Kimberly Garrett

Biological Sciences Undergraduate Honors Theses

Dietary factors can lead to chronic diseases and impact certain health factors such as sleep and mood. Personalized nutrition is based on an individual’s phenotype and genotype to meet specific dietary needs. This approach could be an intervention to benefit an individual’s health. This study surveyed a population to analyze the population’s view on and usage of personalized nutrition. The use of personalized nutrition was minimal, but there was interest within the population. In addition, a relationship between health and mood was found. However, the sample size was a limiting factor for this study. Future directions could include studying why …