Biology Commons^™

Thermal Tolerance, Physiology, And Microhabitat Use Of Eleutherodactylus Coqui Across An Elevational Gradient In Hawai‘I, Jack Marchetti

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The coqui frog (Eleutherodactylus coqui) is an invasive species in Hawai‘i, and has spread across much of the island. While elevational temperature differences are thought to restrict the coqui’s spread, it is unclear if they have resulted in changes to the coqui’s physiology and microhabitat use as it has expanded into higher elevations.

We first sought to determine if the coqui’s substrate use and baseline physiology differs between elevations. We found that frogs at high elevation were found closer to the forest floor and used different substrates than frogs from low and mid-elevations. This change in microhabitat use …

The Effects Of Recent Climate Change On Spring Phenology, With A Special Focus On Patterns Of Bee Foraging, Michael Stemkovski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The date on which plants flower and on which bees begin to pollinate varies year-to-year depending on differences in weather. This seasonal timing is known as phenology, and it is already clear that climate change has pushed the spring phenology of many species earlier by increasing temperatures. This is particularly clear in flowering plants, but studying how and why the phenology of pollinators is shifting is more difficult. Most flowering plants rely on pollinators such as bees for their reproduction, and most bees rely on flowers for their sustenance, so bee and flower phenology has to overlap for the crucial …

Assessing Stream Ecosystem Structure And Function In An Urban Canal And Logan River In Logan, Utah, Ellie Smith-Eskridge

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Humans have constructed canals to support agriculture, to mitigate flooding, and to discharge stormwater, especially in the Intermountain West. These canals are common in Cache Valley, where they receive flows from the Logan River during summer months. However, the ecological structure (e.g., water quality, freshwater invertebrates) and function (e.g., leaf decomposition) of these canals remains largely unknown. Studying ecosystem structure and function of these urban waterways is important because it can inform us of the health of these waterways.

My research had three objectives. First, I compared water chemistry, invertebrate assemblages, and leaf decomposition in an urban canal and the …

Fractally Sampling Diversity-Environment Relationships To Understand Plant Assemblage Health Across Spatial Scales, Elizabeth G. Simpson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Humans influence the health of ecosystems and rely on healthy ecosystems to support their livelihoods and well-being. By looking at how the parts of ecosystems interact we can understand and improve ecosystem health. Ecosystem interactions change across spatial scales or different size patches of area. For example, individual organisms interact with each other at small spatial scales, while at large spatial scales, communities of organisms interact with weather conditions. However, many research studies do not look at how ecosystem interactions change across spatial scales. To address this gap in ecological research, I use a fractal sampling design which samples at …

We Travel Together: Examining The Drivers And Functions Of Animal Movement In Biotic Seed Dispersal, Binod Borah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plants and frugivorous animals exist in mutually beneficial relations, as these animals feed on fruits, ingest the seeds, and carry them away from the parent trees. Such dispersion of seeds over space helps them colonize new habitats, escape high mortality rates near their parent trees, and avoid competition with conspecifics. Therefore, seed dispersing animal movement can be critical for the persistence of plant populations. Yet what drives such seed disperser movement is often less understood and how it affects seed dispersal is little explored. In my dissertation, I investigate multiple drivers of seed disperser movement, link movement to potential seed …

Status And Enhancement Of Trissolcus Japonicus (Ashmead) (Hymenoptera: Scelionidae) For Biological Control Of Halyomorpha Halys (Stål) (Hemiptera: Pentatomidae) In Northern Utah, Kate V. Richardson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The invasive brown marmorated stink bug (BMSB) is a major insect pest that invades human structures causing nuisance issues and attacks numerous fruit and vegetable crops in Northern America. As this pest threatens $23 billion worth of specialty and agricultural crops in the U.S. and is difficult to manage due to insecticide resistance, control practices such as the use of biological control through egg parasitoid wasps are critical. In its native range of Asia, BMSB populations are controlled primarily by members of the Trissolcus genus such as the samurai wasp, but U.S. native wasps have demonstrated low success of BMSB …

Consequences Of Host Life Cycles For Symbiont Genome Evolution, Ashley Elizabeth Dederich

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Aphids are small insects that feed exclusively on plant sap, a notoriously low source of nutrients due to the high sugar content and low amino acid content. To make up for these deficiencies in nutrition, aphids harbor Buchnera aphidicola, a bacterial endosymbiont that resides in a specialized organ called the bacteriome. B. aphidicola provides essential amino acids and vitamins for the aphid in exchange for a safe place to live. Over the course of the symbiosis (established 160 million years ago), B. aphidicola has lost much of its genome, including essential genes for cell envelope synthesis, DNA replication and …

Notes On Lung Development In South African Ghost Frogs (Anura: Heleophrynidae), Jackson R. Phillips, Jens Reissig, Gary Kyle Nicolau

Biology Student Research

Lungs are a prototypical trait of most tetrapods, but some amphibians have become secondarily lungless over evolutionary time. Anuran (frog) tadpoles offer an opportunity to examine lung loss from an evolutionary perspective, because there are many independent instances where lungs are not inflated until adulthood, and so are functionally lost. Lung loss is typically associated with living in fast-flowing streams, and so we examined larval lung development in the stream specialist family Heleophrynidae. We find that one genus, Hadromophryne Van Dijk, 2008, has large lungs as tadpole, while the other genus, Heleophryne Sclater, 1898, has much smaller, stunted lung buds. …

Mapping Of Corticotropin-Releasing Factor (Crf) Receptors In The Coyote Brain, Rachel Tong

Student Research Symposium

Forming strong social bonds is essential to our everyday life and is part of what makes us human. The loss of a loved one often results in grief, stress, and loneliness, and the stress response system of the body has been implicated in the physiological symptoms associated with grieving. The hormone that initiates the stress response in the body is called corticotropin releasing factor (CRF), which acts via binding to CRF receptors (CRFR). Coyotes are an appropriate animal model to study social bonds and social loss because they display monogamy and pair bonding, which is a trait seen in human …

The Water To Land Transition: Changes In Frog Skin Across Development, Kayla Hancey

Student Research Symposium

Amphibians are vulnerable to changes in the environment due to their permeable skin. As the climate changes, the resilience of different species can be illuminated by traits that vary across clades. Skin changes during metamorphosis provide details that may help us anticipate desiccation risk. It is useful to understand histological details in a relatively successful species, such as the American green tree frog (Hyla cinerea) when determining species survivorship. Documentation of skin changes including gland development in H. cinerea has never been done.

Protein Nutrition And Immunity In Male Bumblebees Of Bombus Impatiens, Carson Stoker

Student Research Symposium

Male bumblebees play a vital but undervalued role in their colonies. They are important to colony reproduction and success despite not emerging until the end of the colony's life cycle. Little research has been conducted on the biology and the role of male bumblebees. Further understanding could lead to heightened colony success in agricultural and environmental conditions. The objectives of this study are to 1) understand the effect of protein nutrition on the melanization responses of male bumblebees, 2) measure gene expression of various immune genes after an immune challenge with different diet conditions, and 3) further scientific knowledge about …

Obstacles To Usu Prehealth Students In Applying To Medical School, Cory Watts

Student Research Symposium

Every year tens of thousands of students apply to medical schools across the nation. Despite successful completion of undergraduate degrees, current matriculation rates range between 40% and 50% each year. Matriculation rates at Utah State University experience some fluctuation, but in the past 5 years matriculation rates have fluctuated around 60% to 75%. Within this larger number though, only 17% to 30% of Utah State applicants are getting accepted to MD programs. As part of a nation wide survey being conduced by Tyra-Lee from the AMSA National Board of Trustees, we sought responses from current students at USU to better …

Ethical Issues With Schizophrenia Research And Treatment, Chloé Brogdon

Student Research Symposium

Schizophrenia is a complex and debilitating mental disorder that affects millions of individuals worldwide. As researchers and practitioners seek to better understand and treat this condition, it is crucial to consider the ethical implications of research and treatment approaches. This project investigated the nature and scope of schizophrenia as an illness in order to delve into ethical issues with current research and treatment approaches. Ethical issues identified and analyzed include issues with informed consent, stigmatization, and access to treatment.

Netosis In Naked Mole-Rats: A Step Towards Cancer Resistance, Thomas Smith

Student Research Symposium

The purpose of this project is to identify and characterize neutrophil extracellular traps (NETs) in Naked Mole Rats (NMRs) as a step towards understanding their remarkable cancer resistance. The vision is that in doing so we can translate this understanding to human cancer research in ways that could eventually open new clinical treatment methods. Naked mole-rats are incredibly cancer resistant, and yet they possess immune cell ratios more similar to humans than to mice. Neutrophils are the most abundant immune cell in humans. They release neutrophil extracellular traps (NETs), a process referred to as NETosis, as part of an immune …

The Kinematics Of Motor Planning Span, Megan Sparks

Student Research Symposium

In the Sensory Motor and Behavior Lab, we are developing a new measure of motor planning span. Motor planning is defined as preparing for movement before any movement occurs. This is a critical process that allows us to do any and all physical activity. The ability to do motor planning can be impacted after a traumatic brain injury or in the case of having a neurological disorder such as Autism Spectrum Disorder. Many studies have looked at motor planning span with discrete starting and ending positions, but our study will be analyzing continuous movements. We will collect reaction time, movement …

Compound Drug Treatment Of Yellow Fever Virus: Evaluation Of Compound X In The Enhancement Of Favipiravir Potency In A Hamster Model Of Yellow Fever Virus Infection, Hunter Stanger

Student Research Symposium

Yellow fever virus (YFV) has long been a worldwide health concern, and recent outbreaks in South America have resulted in significant mortality. Though there is an effective preventative vaccine, currently there are no antiviral compounds approved to treat those already infected. The nucleoside analog drug favipiravir is shown to significantly improve disease signs but is toxic in effective doses. Compound X has been shown to have synergistic effects with favipiravir by increasing the amounts of active favipiravir (ribosylated favipiravir triphosphate) in cell culture. In this study, we administered suboptimal doses of favipiravir with fixed doses of compound X to determine …

The Grieving Brain: Effect Of Pairmate Loss On Coyote Oxytocin Receptor Densities, Kaleb Keller

Student Research Symposium

Complicated grief is a severe mental health disorder that can have detrimental effects on individuals who have lost a loved one. Understanding the biological underpinnings of grief is essential in being able to help develop effective treatments and therapies. Oxytocin is heavily implicated in studies about grief and pairmate loss due to its importance in modulating social behavior such as pair bond formation. Previous research has primarily focused on rodents and non-human primates as model organisms of social attachment and studies have shown that monogamous prairie voles showed a decrease in oxytocin receptor (OXTR) binding in the nucleus accumbens after …

Natural Product Biosynthesis Through Biotechnological And Fermentation Approaches, Hassan Sher

Student Research Symposium

Natural products as a source of medicine have long been attractive due to the huge structural diversity and promising biological activities such as antimicrobial, anticancer, antitumor, antifungal, antiviral, antiparasitic as well as antioxidant properties. Discovery of novel and modified natural products is the need of this modern era. To expand the chemical diversity in natural products and to increase the production titers of natural products, researchers have come up with various solutions: heterologous expression, cocultivation, fermentation engineering, isolation of new species, and strain engineering/improvement. o-Coumaric acid and p-coumaric acid are phenolic antioxidants found in various plant sources. These also serve …

Glycosylation Of Anti-Tb Agent Chlorflavonin For Combating Mycobacterium Tuberculosis, Jie Ren

Student Research Symposium

More than two billion people were infected by the bacterial pathogen Mycobacterium tuberculosis (Mtb) in 2020. However, during the past 50 years, the first-line (isoniazid, delamanid, and rifampicin) and second-line (capreomycin, streptomycin, and cycloserine) therapies have remained unchanged with disadvantages such as long treatment periods and severe side effects. The slow development of anti-TB drugs cannot combat the fast development of drug resistant M. tuberculosis strains from multidrug-resistant (MDR) into extensively drug resistant (XDR), which further hinders the World Health Organization’s goal to end the global TB pandemic by the year 2035. Flavonoids are a type of natural product with …

Does Diet Effect The Brain?, Janna Hart

Student Research Symposium

Short-chain fatty acids are biomolecules produced from bacterial fermentation of dietary fiber in the gut. Short-chain fatty acids are used in the gut to supply energy and reduce inflammation but are also believed to have effects on the brain. While we do not know how short-chain fatty acids affect the brain and behavior, recent research has led to the idea of using dietary changes as a treatment for mental health disorders. In my research, we aimed to visualize where short-chain fatty acids act in the brain with a particular focus on neural immune cells called microglia and the neurons that …

Catchment Protections Enhance River Resilience To Water Quality Perturbations, Allyson Marrs

Student Research Symposium

Around 40% of rivers in the United States have been increasing in salinity in recent decades. This salinization is caused by natural and anthropogenic processes, such as applying salts to roads for deicing purposes. Rapid increases in salinity in freshwater streams can have negative impacts on drinking water, infrastructure, and biodiversity. However, catchment protections may offer resilience to water quality degradation. Using a weighted regression on time, discharge, and season, we analyzed long-term trends in specific conductance in the Yellowstone River at Corwin Springs. The majority of the Yellowstone River upstream of this site lies on federally protected lands with …

Changes In Metal-Chelating Metabolites Induced By Drought And A Root Microbiome In Wheat, Anne J. Anderson, Joshua M. Hortin, Astrid R. Jacobson, David W. Britt, Joan E. Mclean

Biological Engineering Faculty Publications

The essential metals Cu, Zn, and Fe are involved in many activities required for normal and stress responses in plants and their microbiomes. This paper focuses on how drought and microbial root colonization influence shoot and rhizosphere metabolites with metal-chelation properties. Wheat seedlings, with and without a pseudomonad microbiome, were grown with normal watering or under water-deficit conditions. At harvest, metal-chelating metabolites (amino acids, low molecular weight organic acids (LMWOAs), phenolic acids, and the wheat siderophore) were assessed in shoots and rhizosphere solutions. Shoots accumulated amino acids with drought, but metabolites changed little due to microbial colonization, whereas the active …

Consistent Nest Site Selection By Turtles Across Habitats With Varying Levels Of Human Disturbance, Molly Folkerts Caldwell, Jorge E. López-Pérez, Daniel A. Warner, Matthew E. Wolak

Biology Student Research

Human disturbance impacts the breeding behavior of many species, and it is particularly important to understand how these human-caused changes affect vulnerable taxa, such as turtles. Habitat alteration can change the amount and quality of suitable nesting habitat, while human presence during nesting may influence nesting behavior. Consequently, both habitat alteration and human presence can influence the microhabitat that females choose for nesting. In the summer of 2019, we located emydid turtle nests in east-central Alabama, USA, in areas with varying levels of human disturbance (high, intermediate, low). We aimed to determine whether turtles selected nest sites based on a …

Sheep Ingestive Behavior And Tannin Selection In Pampa Grassland And Feedlot, Marina Terra Braga

Green Canyon Environmental Research Area, Logan Utah

The Pampa grassland biome has high plant biodiversity, some with significant secondary compound concentrations such as tannins. Tannin inclusion in ruminant diets may improve meat quality and productivity. However, voluntary intake of this phenolic compound can be a challenge. This dissertation includes three studies within this context. The first study documented whether sheep consume tannin-rich Desmodium incanum (DI), the most common Pampa herbaceous legume species. The second study evaluated how forage tannin and protein concentration influenced sheep feedlot feed selection and the diet affects performance parameters. The third study evaluated sheep feeding behavior in a Pampa native pasture, and how …

An Automatic System To Evaluate Bait Station Visitation By Brown Treesnakes And Mongooses, Robert T. Sugihara, William C. Pitt, Are R. Berentsen, Francis L. Benevides Jr.

Human–Wildlife Interactions

Understanding the temporal, spatial, and behavioral patterns of the free-ranging target species in response to candidate baits and baiting strategies is important to ensure control success. This information can also assist in the development and deployment of feeding stations and can exclude non-target species while constituting effective bait delivery and control strategies for certain invasive animals, especially at environmentally sensitive sites. We used passive integrated transponder (PIT) tags in conjunction with very-high frequency radio-telemetry to remotely record bait station visitations and evaluate bait attractiveness in separate field research studies of brown treesnakes (Boiga irregularis) on Andersen Air Force …

Pilot Study For Invasive Brown Treesnake Baiting In Residential Areas, Shane R. Siers, Juan-Carlos Mungaray, Jordan I. S. Barcinas, Jeried E. Calaor, Rachel M. Volsteadt, Martin Kastner, Scott M. Goetz, Melia G. Nafus, Thomas C. Hall

Human–Wildlife Interactions

The nocturnal brown treesnake (Boiga irregularis; BTS) was accidentally introduced to the island of Guam, USA, in the Western Pacific in 1945. The BTS has spread throughout all terrestrial habitats, causing wildlife loss and economic damage. Several tools and techniques have been developed to locally reduce BTS numbers and prevent their spread to other islands. The common analgesic acetaminophen has been registered as a low-risk pesticide to manage BTS in non-residential areas. Prior to a more intensive toxic baiting campaign on Andersen Air Force Base, Guam, as part of a larger study to evaluate the effects of BTS …

Human–Alligator Incidents In The United States: Risky Human Behaviors Cause Most “Attacks”, Mark S. Teshera, Azar Kordbacheh, Frank J. Mazzotti

Human–Wildlife Interactions

Interactions between humans and American alligators (Alligator mississippiensis), often resulting in negative outcomes for both participants, have occurred for centuries in the United States. As both populations increased over time, contact and conflict with one another became inevitable. Although human–alligator conflicts have been well documented, there has been no detailed classification of risk factors associated with human activities immediately preceding, and in most cases precipitating, an encounter. Herein, we provide a ranking system to categorize different human activities, based on risk levels, immediately preceding an encounter with an alligator. To complete our review in 2021, we initially gleaned …

Human–Black Bear Interactions And Public Attitudinal Changes In An Urban Ordinance Zone, Mark A. Barrett, Sarah E. Barrett, David J. Telesco, Michael A. Orlando

Human–Wildlife Interactions

Human–bear (Ursus spp.) interactions (HBI) commonly occur in residential areas throughout North America. Negative HBI can be alleviated by using bear-resistant garbage cans (BRC) and by securing other bear attractants (e.g., bird feeders). Since the early 2000s, human and Florida black bear (U. americanus floridanus) densities have increased substantially throughout Florida, USA, concurrently producing an increase in HBI. In central Florida, an area with high densities of humans and black bears, we surveyed 2 neighborhoods that occurred in an urban ordinance zone established in 2016 that required residents to secure anthropogenic food sources. Residents were supplied with …

Human Fatalities Resulting From Wild Pig Attacks Worldwide: 2000–2019, John J. Mayer, James E. Garabedian, John C. Kilgo

Human–Wildlife Interactions

Although reported to be rare, human fatalities resulting from wild pig (Sus scrofa) attacks do occur. Toward a better understanding of patterns in fatal wild pig attacks, we synthesized worldwide reports of wild pig attacks on humans between 2000 and 2019. We documented 163 separate reports of fatal wild pig attacks that resulted in 172 human deaths. On average, 8.6 human deaths occurred annually due to wild pig attacks during those 2 decades. The majority of fatal attacks resulted in a single human death; however, there were 6 cases in which an individual fatal attack resulted in 2–4 …

Grizzly Bears And Humans At Alpine Moth Sites In Wyoming, Usa, Erika A. Nunlist, Dan Tyers, Andrew Pils, Bok F. Sowell

Human–Wildlife Interactions

Army cutworm moths (Euxoa auxiliaris; moths) are an important seasonal higher elevational food source for grizzly bears (Ursus arctos horribilis; bears) in the Greater Yellowstone Ecosystem (Wyoming, Montana, and Idaho, USA). Increased human interaction with bears at moth sites is an important management issue because of the potential for displacing bears and the concern for human safety. Managers will need better information regarding human–bear interactions at high-density moth sites that are also accessible to humans to mitigate potential conflicts. In the summers of 2017 and 2018, we studied human–bear interactions at 2 of the most human …