Life Sciences Commons^™

Systematics And Comparative Genomics Of The Petaluridae (Odonata: Anisoptera), Ethan R. Tolman

Dissertations, Theses, and Capstone Projects

The Anisoptera (Insecta: Odonata), or dragonflies exhibit diverse life histories and diversification patterns, with the family Petaluridae standing out as particularly unique. Comprising only 11 extant species, all of which inhabit increasingly threatened fen habitats, Petaluridae are known for their longevity, which can exceed five years, semi-terrestrial lifestyle, and remarkable physical size, ranking among the largest insects on Earth. Despite the evolutionary peculiarities of this family, no previous genomic studies have investigated the Petaluridae. This work presents two high-quality genome sequences and a targeted enrichment dataset to explore the chromosome architecture of Petaluridae, identifies genomic adaptations associated with their distinctive …

The Stability Of Epigenetic Variants That Can Act As Loci Causing Phenotypic Change, Raul Faburrieta

Biology Theses

Epigenetic variations are a possible source of heritable phenotypic variation. In this study I focus on phenotypic alterations seen in epigenetic Recombinant Inbred Lines (epiRILs) of Arabidopsis thaliana. These epiRILs allow me to study the effects differentially methylated regions (DMRs) have on phenotypic variance. In a study performed in 2014 by Cortijo et al., they found that DMR’s affect flowering time and root length when grown under greenhouse conditions. In this study, I replicated the Cortijo et al. (2014) study, with some changes, to see whether the same significant eQTL regions are found. I found that, some of the eQTLs …

Lyme Disease In The Northeast: The Unintended Consequence Of Suburban Development, Hayden Neubert

Student Theses 2015-Present

This paper addresses the role of suburban development in the suburbs of the Northeastern United States in increasing human Lyme disease infection. Over the past 50 years, Lyme disease has become the most common vector-borne disease in the United States. In 2021, the two states with the most Lyme disease cases were New York and New Jersey, with a collective 6,524 cases, with Connecticut still representing 541 total cases. It is not a coincidence that case numbers are concentrated in suburban areas with high forest fragmentation. Chapter 1 of this essay analyzes how human land development disrupts bioregulatory ecosystem actors …

From Pixels To Plants: Remote Sensing Of California Invasive Plants, Kenneth Rangel

Master's Projects and Capstones

Invasive plants cause significant impacts to ecosystems, the economy, and human health. California has experienced significant plant invasions and is well suited to future invasion because of its Mediterranean climate and human disturbance. Eradication or control of invasive plant species requires a detailed understanding of their spatial distribution, which typically involves on the ground surveys that can be expensive or inconsistent. Remote sensing offers a potential alternative or supplement to in-person invasive plant mapping. This study performed a comparative analysis of 41 remote sensing studies that mapped the distribution of California invasive plants. I found that while high spectral resolution …

Ancient Wisdom, Modern Prosperity: Harnessing Traditional Ecological Knowledge To Revitalize Australia's Economy, Environment, And Human Wellbeing, Annabelle L. Baulch

Student Theses 2015-Present

This paper explores the traditional knowledge of Australia’s Indigenous people and how it can improve Australia's environment, health, and economic prosperity to shape a more sustainable future. Indigenous Australians managed the land for thousands of years; however, being forced off the land following European colonization resulted in terrible cultural, social, and environmental disruption for Aboriginal Australians and made conservation efforts difficult. Wildfires, imported species, mining, and agriculture is steadily destroying the Australian ecosystem, contributing to climate change, species extinction, and gaps in our cultural and ancestral knowledge. Chapter One overviews Australia's environmental issues; it uses quantitative data to explore the …

Reef Ecosystem Conservation For The Hawaiian Islands: The Impacts Of Ocean Warming And Acidification On Benthic Reef Populations, Samantha Roberts

Student Theses 2015-Present

This paper explores the anthropogenic effects of rapid climate change and ocean acidification on benthic coral populations along the Hawaiian archipelago. Moreover, the reliance of Hawaiian coastal communities on coral reefs for sustenance and economic prosperity is evaluated to determine the importance of reef ecosystem conservation for the prosperity of Hawaii. Chapter 1 introduces the importance of coral and supplies quantitative data on declining coral populations traditional to Hawaii, as a result of ocean warming and acidification. Empirical data from prior, prominent studies, combined with my own, will be discussed. Chapter 2 outlines the ecology of Hawaiian reef ecosystems, the …

Riparian Expansion Post-Restoration Efforts Along The Upper Clark Fork River, Makena Tanko

Graduate Theses & Non-Theses

Floodplain restoration is an intricate process aimed at promoting water quality, biodiversity, and maintaining ecological balance. However, mapping vegetation patterns on a restored floodplain can be challenging due to different geomorphic locations across a river sections, including flooding regimes, sediment characteristics, elevation, and ground water availability. This study investigates the drivers of vegetation succession in floodplains post-restoration along the Upper Clark Fork River, encompassing Phases 1, 2, 3, and 5. We analyzed key factors influencing vegetation response, including total canopy cover and woody vegetation health, in comparison to soil compaction, geomorphic location, distance from streambank, time post-restoration, and metal levels …

Examining Population Structure Of Cismontane And Desert Populations Of Zebra-Tailed Lizards (Callisaurus Draconoides) Using Mitochondrial And Nuclear Intron Dna., Lauren Nicole Morrison

Electronic Theses, Projects, and Dissertations

Callisaurus draconoides, also known as the Zebra-Tailed lizard, belongs to the family Phrynosomatidae family (Pianka, et al. 1972). C. draconoides is a widespread desert lizard found western North America. In California, this species can be found in the Mojave and Colorado Deserts. There are currently several populations that reside in the San Bernardino basin on the cismontane side of the Transverse and Peninsular ranges. These mountain ranges have the potential to have isolated the cismontane populations from their typical desert ranges. In addition, geological passes have the potential to serve as migration corridor between the Deserts and cismontane regions. The …

The Effects Of Aboveground Herbivory On Root Traits And Root Decomposition, Emily A. Chavez

All Graduate Theses and Dissertations, Fall 2023 to Present

Soil holds more carbon (C) than the Earth's atmosphere and vegetation combined. Soil loses carbon through soil respiration and releases CO₂ from the soil. The soil respiration rate can vary based on the chemistry of the plant litter inputs and physical factors, such as soil temperature and nutrient content. In Alaska's Yukon-Kuskokwim (YK) Delta, grazing by geese affects the chemistry of plants and the soil's physical qualities, thus altering the rate of soil respiration. Although we know that goose herbivory leads to changes in the rate of soil respiration, we know very little about how goose herbivory affects the …

Experimental Nonnative Wood Addition Enhances Instream Habitat For Native Fishes And Investigating Dryland River Alterations, Benjamin J. Miller

All Graduate Theses and Dissertations, Fall 2023 to Present

The rivers of the Colorado River Basin (CRB) have been degraded by human activities such flow regulation, water overallocation, and the introduction of invasive riparian vegetation (primarily tamarisk tamarix spp. and Russian olive Elaeagnus angustifolia). These stressors have resulted in widespread habitat loss and simplification, which is a major contributor to the endangerment of native fishes in the CRB.

The objectives of this study were to 1) assess the effectiveness of enhancing native fish habitat by experimentally adding cut wood from nonnative Russian olive to the San Juan River, a highly degraded dryland river, and 2) determine the …

The Influence Of Researcher Disturbance On Raccoon Predation Of American Alligator Nests, Clarissa Tuten

Electronic Theses and Dissertations

Raccoons (Procyon lotor) are a dominant predator of American alligator (Alligator mississippiensis) nests in the southeastern United States, using a combination of olfactory, visual, and tactile cues to identify nest locations. Studies on alligator nesting ecology typically require researchers to create paths through marsh habitat, potentially introducing visual and olfactory cues raccoons may use to locate nests. The purpose of this study was to evaluate the effect of human visitation to alligator nests on the frequency of raccoon nest predation at two sites in coastal South Carolina, Tom Yawkey Wildlife Center (TYWC) and Santee Coastal Reserve (SCR). We hypothesized that …

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 …

Movement Behavior And Habitat Selection Of Juvenile Mountain Lions (Puma Concolor) During Three Behavioral States Of Dispersal, John F. Randolph

All Graduate Theses and Dissertations, Fall 2023 to Present

Juvenile dispersal, the act of moving from their natal range to the place where they eventually reproduce and establish an adult home range is hazardous. Juveniles must travel and find food across unfamiliar landscapes, where they must also cross roads, avoid harvest, and navigate developed landscapes. Despite the inherent dangers of dispersal, this demographic process is important for finding suitable mates and reducing inbreeding depression. Wildlife conservation concerns arise when individuals are unable to disperse due to a loss of connectivity, as this can negatively impact population demographics and genetic diversity. We explored the effects of hunting and human-developed landscapes …

Revegetation Strategies For Native Wetland Plant Restoration In The Face Of Phragmites Australis Reinvasion And Hydrologic Extremes, Maddie Houde

All Graduate Theses and Dissertations, Fall 2023 to Present

Reestablishing native plant communities in degraded habitats through seeding or planting ("revegetation") is a necessary step to restore ecosystems and their functions (e.g., supporting biodiversity, nutrient cycling, etc.). Globally, wetlands have suffered high rates of degradation and also experience numerous invasions. Invasive species are those that cause environmental, economic, or societal harm. Phragmites australis is a widespread invasive species that outcompetes native plants and reduces habitat diversity. Reestablishing native plant communities can limit P. australis invasion, yet effective methods to do so remain somewhat untested in wetlands. Additionally, stressful environmental conditions can increase plant mortality in revegetation efforts. In semi-arid …

Top-Down Vs Bottom-Up Effects On Predator-Prey Interactions In Aquatic Communities, Catherine Mary Mcclure

All Graduate Theses and Dissertations, Fall 2023 to Present

Ecology is studied at multiple scales to better understand how small changes at the individual level scale up to affect our ecosystems and global systems. These ecological scales include individuals (single organism), populations (group of organisms of the same species), communities (populations of different species interacting with each other), and ecosystems (species interacting with other species and their local environment). The research in this document is focused on the individual, population, and community scale. In particular, this research addresses questions regarding how changes in environmental conditions (i.e., predation and resources) affect species interactions which ultimately affects the composition of ecological …

Spatiotemporal Dynamics Of Disease: Social And Environmental Drivers Of Movement, Connectivity, And Disease Transmission In Bighorn Sheep, Lauren E. Ricci

All Graduate Theses and Dissertations, Fall 2023 to Present

Movement is a fundamental component of animal ecology. Animals move in order to access resources and avoid risk. Movement decisions aggregated across time determine how individuals use space, contact dynamics between individuals within a population, and connectivity across a species range. These patterns that emerge from movement decisions have downstream implications for many ecological processes and a mechanistic understanding of movement can help answer broader questions about ecology.

Disease dynamics are intrinsically tied to movement. Understanding the mechanisms that drive movement can elucidate how disease will spread and impact host populations. In this vein, I employed a suite of movement …

Causes And Consequences Of Space-Use Behavior Under Predation Risk In A Free-Living System, Brian J. Smith

All Graduate Theses and Dissertations, Fall 2023 to Present

Predators can have important ecological effects through killing and eating their prey, the so-called consumptive effect, but predators can also have a nonconsumptive effect (NCE) on their prey – this happens when the risk of predation itself causes prey to alter their behaviors or other traits and these alterations ultimately reduce prey survival, reproduction, or population size. While scientists understand the consumptive effects of predators well, we are still unsure whether NCEs are important in free-living systems. In this dissertation, I sought to better understand the potential NCEs of predators (wolves and cougars) on elk in northern Yellowstone National Park …

Impacts Of Urbanization On Demographics And The Stress Level Of White-Tailed Deer In The Piedmont Of South Carolina, Cameron Bramhall

Graduate Theses

Population demographics and density studies are a common way of determining number of individuals in location. Understanding how many individuals and sex ratios can help estimate total populations for future potential management practices. For white-tailed deer (Odocoileus virginianus), commonly referred to as whitetail deer, like other cervids, having too many or too few individuals in an area can cause issues. Some of the issues that may arise with too many individuals include higher disease potential, and a general lack of resources leading to an increase in competition. As areas that were once habitat for whitetail deer become more and more …

Threads Of Connection: An Offering To Re-Tangle Humanity And Nature With The Patterns Of Our World, Emily Shelton

Graduate Theses

In our world there are patterns of self-similarity that serve as evidence of the interconnectedness between humankind and the rest of the natural world. They are reflected in our bodies, behaviors, and environments, both natural and manmade, and can be found throughout systems at every scale, micro through macro. These organic, linear motifs branch into smaller iterations that seem to shape our existence on this planet as we gravitate towards experiences that echo these patterns. During everyday acts like shopping in a grocery store or a crowd at a concert, we unconsciously participate in self-similar collective movements as we navigate …

Evaluating Aspen Seedling Outplanting Success Following High Severity Wildfire In The Southwest, Sarah M. Kapel

All Graduate Theses and Dissertations, Fall 2023 to Present

Quaking aspen (Populus tremuloides Michx.) is an ecologically important forest species in the western U.S. Aspen forests host a variety of understory species, are critical wildlife habitat, and are considered a "natural fuel break" since they are less likely to support crown fires than conifers. Because of climate change and altered disturbance regimes, populations are declining, and innovative strategies are needed to restore aspen. Planting aspen seedlings is a solution, though not a common practice in the West and has been met with high mortality in past experiments. For aspen planting to be more broadly implemented, managers need guidance …

The Spatial And Behavioral Ecology Of The Eastern Box Turtle In A Suburban Landscape, Emma Rogers

All Theses

Urbanization poses a significant threat to wildlife through fragmentation, degradation, and loss of habitats. Species response to urban development is variable, from species that thrive in urban areas to those that avoid them. Eastern box turtles (Terrapene carolina carolina) can live and reproduce in urban areas; however, reports of population decline throughout the species’ range have raised concerns. The objective of this study was to compare home range size and composition, as well as the microhabitat selection of the Eastern box turtle across a developmental gradient in Clemson, SC. We tracked 14 individuals in habitats along a developmental …

Models Of Functional Redundancy In Ecological Communities, Sandra Annie Tsiorintsoa

All Dissertations

Functional redundancy is the number of taxa that perform a given function within a given community. In most systems, high levels of functional redundancy are important, because they contribute to ecosystem stability. However, we currently have very little understanding of why functional redundancy varies among communities. One possible factor that could affect functional redundancy is environmental complexity. Many studies show that simplified ecosystems harbor communities with lower taxon diversity. What is less clear is if this simplicity and lower taxon diversity also affects functional redundancy. To answer this question, we use metacommunity models to explore the connection between environmental complexity …

Survey Of The Bolctes From Fish River Nature Preserve, Noah T. Nelson

Honors Theses

Boletes are a special kind of mushroom inside of the Kingdom Fungi that are distinguished from other mushrooms by their uniquely pored hymenium, as opposed to gills. Many boletes are ectomycorrhizal, meaning they are mutualists with vascular plants, and thus beneficial to the overall health of the terrestrial ecosystem. Some are well-known for their edibility and are of economic importance. In the United States 59 genus-level clades comprising 290 operational taxonomic units have been reported. The southeastern US and Gulf Coast regions however are less researched and recorded for their mushroom ecology. In Alabama, only 56 bolete species have been …

A Phylogenetic Analysis Of The Population Dynamics Of A Captive Colony Of Diploptera Punctata., Nick Peterson

Theses/Capstones/Creative Projects

The unique milk production of Diploptera punctata makes this species a promising model species in entomology for studying the evolution of milk production and for insect endocrinology. Despite this, the genetic diversity of captive populations of the species is not well studied. To better evaluate the captive diversity and population dynamics of Diploptera punctata at UNO we extracted the DNA of 20 random individuals and amplified their DNA using 4 different primers before cleaning the amplified products and sequencing the genes of the samples for use in both individual and concatenated phylogenetic trees. Our results indicate the UNO colony of …

The Effect Of An Oak Savanna Habitat Restoration On Bat Activity In Eastern Nebraska, Aidan Hatfield, Jeremy White

Theses/Capstones/Creative Projects

Oak savanna habitat has been drastically reduced throughout the Midwest. Temperate bats generally are edge adapted and may better utilize a restored oak savanna habitat than the now common deciduous forests that replaced them. Therefore, we analyzed the activity of 7 bats native to eastern Nebraska and in the process, compared the agreement of two different programs that claim to automatically identify bat species. In order to investigate this, we placed three audio detectors within both habitats for 1 week and allowed them to record from sunset to sunrise. The data obtained was analyzed and compared between two programs, Kaleidoscope …

Monitoring Selenium Bioaccumulation In False Map Turtles (Graptemys Pseudogeographica), Grant M. Budden

Honors Thesis

Selenium is an element that becomes bioactivated in aquatic environments. Selenium bioaccumulation may threaten a South Dakota state-threatened species, the False Map Turtle (Graptemys pseudogeographica). Invertebrate filter feeder species like zebra mussels (Dreissena polymorpha) uptake selenium via exposure. Previous laboratory work has found that False Map Turtles consume large amounts of zebra mussels throughout the summer, leading to selenium bioaccumulation from selenium transfer from prey to predator. A myriad of adverse effects, like selenosis, reproductive infertility, and death, are associated with high selenium concentrations. Sampling was completed on False Map Turtles in the summer of 2022. …

Trophic Ecology Of Black Swallowers (Scombriformes: Chiasmodontidae: Chiasmodon) In The Deep-Pelagic Gulf Of Mexico, Travis J. Kirk

All HCAS Student Capstones, Theses, and Dissertations

The ecology of deep-pelagic predatory fishes remains poorly understood despite their importance as ecosystem regulators and energy transfer vectors. This study investigated the trophic ecology of three species of the predatory fish genus Chiasmodon (“black swallowers”) in the Gulf of Mexico, a region that serves as an analog for the global low-latitude deep pelagial, the world’s largest cumulative ecosystem. Foraging habits (e.g., selectivity, chronology, daily ration) of an “advanced” evolutionary fish in a system that is otherwise dominated by basal fish taxa, were quantitatively estimated via high-resolution stomach content analysis. A quantitative dataset of both predator and prey abundance, the …

Euhaplorchis Sp. A Effect On Social Behavior And Familiarity Of Gulf Killifish (Fundulus Grandis), Hannah Bauman

All HCAS Student Capstones, Theses, and Dissertations

Trophically transmitted parasites may manipulate their hosts’ phenotype (e.g., behavior, physiology, morphology) to increase the likelihood of transmission to the definitive host. In fishes, stable social groups develop familiarity over time through repeated interactions among individuals, and social preferences are often developed due to familiarity. Consequently, fishes often shoal with familiar fishes, a behavior that is likely to be protective against predation. Parasites may alter fish social dynamics in two ways: by decreasing association with familiar individuals, thereby isolating infected fish and making them more susceptible to predation by definitive hosts; and/or by incentivizing uninfected individuals to avoid infected fish …

Understanding Mechanisms Underlying Changes In Parental Care Behaviour In Response To Perceived Paternity In Sunfish, Emma Churchman

Electronic Thesis and Dissertation Repository

Parental care is essential for the survival of many young animals but presents significant costs to the caring parent. To mitigate these costs, parental care systems have evolved to optimize survival and fitness. According to parental investment theory, care allocation is influenced by the offspring’s value, which is often linked to their relatedness to the parent. In this thesis, I explore how hormones and gene expression influence parental care, focusing on bluegill sunfish (Lepomis macrochirus) and the hybrids they produce with pumpkinseed sunfish (Lepomis gibbosus). By manipulating direct and indirect paternity cues – swapping eggs between …

The Decline In Monarch Butterfly, Danaus Plexippus, Populations: An Example Of The Global Threat To Biodiversity, Olivia Sidoti

Honors Projects

Biodiversity encompasses the variety of all life on Earth and how these aspects of nature interact with each other. To have stable and abundant biodiversity, vast amounts of species and organisms are required within an ecosystem. As a result of the increase in negative impacts of human activities and behaviors on the health of nature, biodiversity has been decreasing. An example of the decrease in biodiversity is depicted by the recent decline of the monarch butterfly species. The monarch butterfly is an iconic North American insect that is experiencing a decline in its population due to threats such as deforestation, …