Biology Commons^™

Species Dispersal Modes In Amphitropical Plant Species Of North And South America, Samera Lemma Mulatu

Honors College Theses

Amphitropical disjunct plants are species that occur in both North and South America but not in the intermediate equatorial region. How amphitropical species dispersed across the Americas to their current distribution remains uncertain. To explain amphitropical distributions, three hypotheses were developed to test that (1) species dispersed successively through island hopping across the tropical zone in temperate microhabitats (= stepping stones), (2) species came to their current distribution through vicariance, or (3) species dispersed by a single long distance dispersal event. Twenty-five species were studied to infer their historical distributions with species distribution models in MaxEnt. Distribution models for each …

The Effects Of Auditory Predator Cues On Foraging Patterns In Peromyscus Polionotus, Christina L. Sartain

Honors College Theses

Abstract:

While it is established that animals react to predator cues, little research has been done to assess its effect on foraging patterns and behavior. Foraging patterns are determined by a variety of factors associated with perceived predation risk, such as vegetation cover and moonlight exposure. Predator cues come in many forms, both direct and indirect, and are another indicator of perceived predation risk. Past research suggests that oldfield mice, Peromyscus polionotus, may react to indirect cues (i.e vegetation cover) more often than some direct cues, such as urine of a predator. Other indirect cues, such as vegetation cover and …

Effect Of Fire Suppression On Aquatic Invertebrates In Ephemeral Wetlands Embedded In Longleaf Pine Forests, Hailey E. Baker

Honors College Theses

It has been established for many years that longleaf pine forests require the ecological disturbance of fire in order to maintain a balanced ecosystem. However, a crucial part of these forests has become nearly excluded from prescribed burning. Ephemeral wetlands embedded within longleaf pine forests are a unique and dynamic seasonal habitat that provide homes, refuge, and breeding grounds for a large array of taxa. Past research suggests that fire suppression around ephemeral wetlands is causing harm to many species of amphibians and other herpetofauna, especially threatened species like the flatwoods salamander. However, other species have not been as well …

Presence Of Dirofilaria Immitis In Mosquitoes In Southeastern Georgia, Angelica C. Tumminello

Honors College Theses

Canine heartworm disease is caused by the filarial nematode Dirofilaria immitis, which is transmitted by at least 25 known species of mosquito vectors. This study sought to understand which species of mosquitoes are present in Bulloch County, Georgia, and which species are transmitting canine heartworm disease. This study also investigated whether particular canine demographics correlated with a greater risk of heartworm disease. Surveillance of mosquitoes was conducted in known heartworm-positive canine locations using traditional gravid trapping and vacuum sampling. Mosquito samples were frozen until deemed inactive, then identified by species and sex. The mosquitoes were then either dissected under …

Steady Heartbeat: Field And Laboratory Studies Indicate Unexpected Resilience To High Temperatures For The Ribbed Mussel Geukensia Demissa, Ashlyn N. Smith Ms.

Honors College Theses

Salt marshes are important ecosystems found along the coast of Georgia. Salt marshes are hosts to diverse organisms that interact with each other to promote many ecosystem services, such as storm buffering and flooding, and absorption of excess nutrients. Among these diverse organisms is the ribbed mussel, Geukensia demissa. Mussels are a foundation species in this intertidal landscape, and without them the whole salt marsh would be negatively affected. The purpose of this investigation was to explore the thermal stress response of G. demissa to rising temperatures. Mussels were collected from three locations that were landlocked, close to a …

The Role Of Reactive Oxygen Species In The Gut Immune Response Of Cat Fleas (Ctenocephalides Felis), Clark Hall

Honors College Theses

Fleas transmit numerous deadly and debilitating diseases, including the causative agents of murine typhus and plague. Because initial entry of these infectious agents occurs while blood feeding, the immune response in the flea gut is considered to be the first line of defense against invading microbes. However, relatively few studies have identified the flea immune molecules that effectively resist or limit infection in the gut. In other hematophagous insects, an immediate immune response to imbibed pathogens is the generation of reactive oxygen species (ROS). In this study, we utilized cat fleas (Ctenocephalides felis) to investigate whether natural infections …

Assessment Of The Toxicological Effects Of Cnt-Ab In Mice Followed By Microwave Hyperthermia 14 Days Post Treatment., Andrew C. Mixson

Honors College Theses

Serious side effects and treatment resistance are the main impediments to successful cancer therapy. A variety of nanoparticles have been used for localized, site-specific treatment that prevent or circumvent these impediments. Microwaves alone have been previously used for thermal ablation of various tumors, setting precedence for their successful use in live organisms. In cell culture studies, it has been observed that multiwall carbon nanotubes (MWCNTs) instantly and efficiently absorb microwaves, causing hyperthermia of cells in direct contact with them with unnoticed harm to other cells. It is hypothesized that a treatment can be developed based on a safe microwave heating …

Discovery And Optimization Of Anti-Cancer Properties Of Traditional Herbal Medicines Using Zebrafish-Human Tumor Xenografts, Ashleigh M. Solheim

Honors College Theses

Cancer is one of the most well-known diseases around the world. It hurts everyone in some way, whether they have it themselves or they know someone that is diagnosed. But the problem is not just this brutal disease, the problem is its invasive treatments. The most common treatments for cancer have harmful and painful side-effects that occur in most cases. As a solution to invasive cancer treatments, this experiment is testing herbal medications Neem, Nilavembu, Ashwagandha and Tulsi as potential nontoxic cancer treatments. First, the maximum tolerable dosage for each herbal agent was found. This dosage was used for the …

Comparing Water Quality For Aquaponics Systems With Different Solids Removal Methods And Biofilter Media, And Effluent Output To Grow Beds, John W. Cutt, Heather M. Joesting, Brigette A. Brinton

Honors College Theses

Aquaponics is a closed-loop, sustainable method of food production that combines fish and plant production. This method of agriculture has the potential to bring fresh, local food to food-insecure areas, but challenges remain due to high operating costs. In order to develop a strong aquaponics industry, the creation of the most efficient system designs will be critical in optimizing production. This study’s purpose was to compare water quality between two aquaponics system designs that differ in filtration and solid removal methods. System 1 used a sock filter for solid removal and Kaldnes media for biofiltration while System 2 used a …

The Combined Effects Of Chemicals Used In Textile Processing On Plankton Communities., Diana Wilson

Honors College Theses

Industrial discharge, such as textile effluent, is a major source of chemical mixtures to surface waters. The effects of these mixtures on interacting aquatic organisms can be difficult to predict. We hypothesized that individual chemical effects on phytoplankton and a zooplankton grazer are altered by the presence of other chemicals in mixtures. Microcosms containing a phytoplankton food source (Chlorella sp.) and a zooplankton grazer (Daphnia magna) were exposed to THPC, ammonium, and hydrogen peroxide in a fully crossed design in a greenhouse for one week. Phytoplankton abundance was quantified and zooplankton response was measured as mortality and …

Close Quarters: Seasonal Cestode-Microbe Interactions Within The Guts Of Two North American Sorex Shrew Species, Timothy L. Odom Jr

Electronic Theses and Dissertations

The mammalian gut microbiome has shown to be essential to host fitness and health assisting in both nutrient acquisition from diet as well as protection from pathogens and can include beneficial bacteria as well as parasites such as helminths and protozoans. In this study, I analyzed the cestode and bacterial communities found in the intestines of two North American species of shrew, Sorex monticola and Sorex cinereus. Specimens were collected approximately every three weeks from May to October during 2016 and 2017 as well as during April and May of 2018 and September of 2009 from the Sangre de …

Plasticity And The Impact Of Increasing Temperature On A Tropical Ectotherm, Adam A. Rosso

Electronic Theses and Dissertations

Organisms may respond to climate change through behavior, genetic adaptation, and/or phenotypic plasticity. Tropical ectotherms are thought to be especially vulnerable to climate change because most have a narrow range of thermal tolerance while living close to their upper thermal tolerance limits. Additionally, many tropical species live in closed-canopy forests, which provide homogenous thermal landscapes that prevent behavioral compensation for stressfully warm temperatures. Finally, tropical ectotherms are thought to have decreased capacity for phenotypic plasticity because they have evolved in thermally stable environments. We tested gene expression patterns and phenotypic plasticity in the Panamanian slender anole by a) measuring changes …

Predator-Based Selection And The Impact Of Edge Sympatry On Components Of Coralsnake Mimicry, Lauren E. Wilson

Electronic Theses and Dissertations

Studying warning coloration and mimicry is an effective way to understand predator-driven selection and phenotypic diversity. The presence (sympatry) or absence (allopatry) of a toxic model plays a role in shaping mimetic phenotypes. However, the impact of edge sympatry and allopatry on predation of mimetic phenotypes is not well understood. We studied coralsnake mimicry to test how edge sympatry and allopatry affect predation on mimetic phenotypes. Specifically, we tested 1) if overall attack rates varied with edge sympatry of coralsnakes 2) which color patterns conferred a fitness advantage 3) which specific mimetic signal components are important in driving predatory attacks …