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Anoxia And Re-Oxygenation At Colder Temperatures In Goldfish (Carassius Auratus): Effects On Oxidative Stress And Metabolites, Matthew E. Trzcinski

Theses and Dissertations (Comprehensive)

Under the ice of ponds and lakes, goldfish (Carassius auratus) can survive weeks of anoxia at low temperatures by conserving ATP and by reducing their metabolic rate and relying on liver glycogen stores to meet their ATP demands using glycolysis. The following period of re-oxygenation is also known to be damaging in most vertebrates because it can lead to the generation of reactive oxygen species (ROS) that can cause oxidative damage to lipids, proteins and nucleic acids. Anoxia tolerant vertebrates such as the goldfish and crucian carp (Carassius carassius) accumulate reduced molecules with anoxia, overwhelming the …

Quantifying Ecological Processes Predicting Barren-Ground Caribou (Ɂetthën; Rangifer Tarandus Groenlandicus) Occurrence Across A Heterogenous Northern Indigenous Protected And Conserved Area., Eric Jolin

Theses and Dissertations (Comprehensive)

Northern ecosystems are experiencing a period of rapid and unprecedented change, with implications for species distributions, mammal community dynamics, and habitat associations. Understanding the ecological processes that shape species distributions is crucial for developing effective conservation strategies that can adapt to such change. This study examines drivers of barren-ground caribou occurrence, a species of cultural and ecological significance, across Thaıdene Nëné Indigenous Protected Area, an ecologically intact landscape of high habitat heterogeneity straddling the treeline of the Northwest Territories. I use spatial and temporal variation in caribou detections generated by camera traps to test the relative importance of apparent competition, …

Npr1 As A Temperature-Sensitive Regulator Of Pipecolic Acid-Mediated Plant Systemic Immunity, Spencer Tout

Theses and Dissertations (Comprehensive)

Healthy plant development requires balancing both abiotic (e.g. climate) and biotic (e.g. pathogen) challenges, which intercept important signaling pathways in plants. For example, climate change-associated elevated temperature can negatively modulate various aspects of plant immunity, including the production of central immune signals salicylic acid (SA) and N-hydroxypipecolic acid (NHP). Since SA and NHP signaling both require the master immune co-activator protein NON-EXPRESSOR OF PATHOGENESIS-RELATED GENES 1 (NPR1), it is important to investigate NPR1 as a potentially temperature-regulated molecular hub. Although the NPR1 gene is not transcriptionally downregulated at elevated temperatures (28° C vs. 23° C), little is known about …

Timing Of Migration And Seasonal Movements Of Arctic Grayling (Thymallus Arcticus) In Relation To Water Temperature In The Kakisa River And Upper Mackenzie River, Nwt: Results From An Acoustic Telemetry Study., Levi Snook

Theses and Dissertations (Comprehensive)

Arctic grayling (Thymallus arcticus) are a cold-water salmonid that inhabit waterbodies throughout the circumpolar regions of the northern hemisphere. In the last decade, Ka'a'gee Tu First Nation members as well as local sport fishers, have observed lower catches of Arctic grayling during their annual spawning run in the Kakisa River, NWT. Many potential causes of this decline have been hypothesized including climate change and over harvesting. Outside of the general annual spawning activity in the headwaters of the Kakisa River, the ecology of the population, including post-spawn habitat use and migratory patterns, remained understudied. To address these knowledge gaps, acoustic …

Characterizing The Targeting Of Toc159 Receptors To The Chloroplast Outer Envelope Membrane And Their Role In The Assembly Of Distinct Toc Complexes, Michael Fish

Theses and Dissertations (Comprehensive)

Global agriculture and food security face challenges from climate change, population growth, and other human-driven pressures. Enhancing our understanding of plant biology, particularly chloroplast function, is critical for improving crop yield and stress resilience. As the sites of photosynthesis and key regulators of plant responses to environmental cues, chloroplasts depend on the precise import of thousands of nuclear-encoded proteins to maintain their biogenesis and function. While much is known about the core translocon components in the chloroplast outer envelope membrane that form the TOC complex, the mechanisms underlying their targeting, assembly, and regulation remain incompletely understood.

Plastids, including chloroplasts, evolved …

Macroinvertebrate Communities And Food Web Structure In Tundra Streams Are Shaped By Substrate Size And Beaver Impoundments, Mathew K. Mervyn

Theses and Dissertations (Comprehensive)

North American beavers (Castor Canadensis) are expanding their range into the Arctic tundra as climate change drives earlier ice and snowmelt, and increased shrub cover. As ecosystem engineers, beavers build dams that alter water chemistry by creating impoundments within streams, trapping sediment and organic matter, and modifying nutrient cycling. This thesis evaluates how beaver impoundments interact with natural geomorphic variation in tundra streams and how impoundments affect tundra freshwater ecosystems in the western Canadian Arctic.

In Chapter 2, I compared water chemistry and benthic macroinvertebrate (BMI) community composition across 16 stream reaches, including those with and without beaver dams, with …

Feeling Blue: The Effects Of Blue Light Exposure On Reproduction And Physiology In Drosophila Melanogaster, Laura Hampel

Theses and Dissertations (Comprehensive)

Blue light, the wavelengths ranging from ~400-500 nm, is emitted from the sun and more recently, by artificial lights including those in technology. In humans, prolonged exposure to blue light has been consistently linked to circadian rhythm disruption and retinal damage, and has also been associated with changes in neurodegeneration, aging, mortality, and oxidative stress in model organisms. This thesis explores the multifaceted effects of blue light exposure through two independent but complementary approaches. An initial rapid review of the current state of knowledge on blue light induced oxidative stress in humans was conducted. This revealed that the most studied …

Long-Term Increases In Wing Length Occur Independently Of Changes In Climate And Climate-Driven Shifts In Body Size, Tiffany Dias, Nathan P. Lemoine, Scott W. Yanco, Marketa Zimova, Rachael A. Bay, Brian C. Weeks

Biological Sciences Faculty Research and Publications

Recent widespread reductions in body size across species have been linked to increasing temperatures; simultaneous increases in wing length relative to body size have been broadly observed but remain unexplained. Size and shape may change independently of one another, or these morphological shifts may be linked, with body size mediating or directly driving the degree to which shape changes. Using hierarchical Bayesian models and a morphological time series of 27 366 specimens from five North American migratory passerine bird species, we tested the roles that climate and body size have played in shifting wing length allometry over four decades. We …

Thermal Tolerance Limits Of Mesophotic Corals In American Samoa, Daniel Barshis, Veronica Z. Radice, Katherine E. Parker, Nicholas Evensen

Biological Sciences Faculty Publications

We analyzed the thermal tolerances of multiple coral species from an upper mesophotic (38–40m) and a shallow reef (5–10m) with our portable Coral Bleaching Automated Stress System (CBASS). Depth generalist Montipora grisea (deep and shallow) and depth specialists Pachyseris speciosa and Leptoseris sp. (deep only) were assayed from Leone, located on the western coast of Tutuila in American Samoa. Fragments from 10 genotypes of each species were exposed to a 17-hour thermal stress assay reaching four maximum temperatures ranging from 30–38°C under in situ light conditions (150 μmol photons m⁻² s⁻¹ under a Lee Filters “deep …

Investigating The Role And Expression Of Aquaporin 10 Paralogs In Spiny Dogfish (Squalus Acanthias), Esosa Omoregie

College of Graduate Studies: Theses & Dissertations

Aquaporins (AQPs) are integral membrane proteins that facilitate the selective transport of water and small solutes across cell membranes, playing essential roles in maintaining osmotic balance in vertebrates. Among them, aquaglyceroporins such as AQP10 are capable of transporting water, glycerol, and urea, contributing to osmoregulatory and metabolic processes. This study investigated the expression, localization, and potential physiological roles of two AQP10 paralogs, AQP10C1 and AQP10C2, in the spiny dogfish (Squalus acanthias), a marine elasmobranch that maintains osmotic equilibrium through urea retention and ion regulation. Using RT-PCR, quantitative PCR, Western blotting and immunohistochemistry the study identified tissue-specific expression patterns of …

Backyard Chimeric Microbiomes: K-12 Participatory Science, Abigail Saucier

Honors Theses and Capstones

The US education system has seen a recent push for more secondary school curriculum to include STEM (Science, Technology, Engineering, and Mathematics) materials and activities. Middle and high school is a pivotal time when academic and personal experiences affect the development of student attitudes towards STEM (Christensen et al., 2015; Moreno et al., 2016). Teachers often utilize hands-on activities to promote student engagement with science curriculum (Brooks & Poles, 2021; Christensen et al., 2015). Hands-on activities improve student learning, but impacts vary by type of activity. When students work towards a known outcome they can feel disconnected from the work …

No Detected Signal Of The 2022 Epizootic From Multiannual Diadema Antillarum Settlement Data In The Florida Keys, Jason Albrecht

Theses, Dissertations and Culminating Projects

The sea urchin Diadema antillarum is a key coral reef grazer that remains functionally extinct on many Caribbean reefs following a mass mortality event in 1983–84. In 2022, another widespread mortality event, likely caused by a scuticociliate parasite, again decimated D. antillarum at reefs across the Caribbean. Understanding the population-level impacts of this recent epizootic will be important for coral reef conservation efforts. This study examines multi-year larval settlement data from the Florida Keys to determine if the 2022 mortality event reduced larval settlement. Larval settlement was assessed monthly at three long-term monitoring sites (Delta Shoal, Tennessee Reef, and Pickles …

Journal Of Earth And Life Science, Academic Year 2024-2025, Megan Boche, Nathan D. Pyburn, Ben Hoover, Jayden R. Alsleben, Hector Montoya, Jr, Reed Cumberland, Rose Kuhlmann, Ray Anderson, Ellie Isakson, Seth Sisneros-Martinez, Zanden Mellen, Quady Bernu, Cian Verbridge, Benjamin D. Strei, Madelaine Adamich, Arian Garcia, Tegwen Romportl, Sandra J. Marcu, Bemidji State University

Journal of Earth and Life Science

No abstract provided.

Size Structure Of Black Crappie And Bluegill In Northern, Eastern, Western, And Southern Minnesota, Ray Anderson

Journal of Earth and Life Science

Fish size structure is an important factor in a fishery population. Panfish such as black crappie Pomoxis nigromaculatus and bluegill Lepomis macrochirus play a major role in the health of fisheries. Five lakes from southern, northern, eastern, and western Minnesota were selected for analysis. Data were collected using standard sampling methods, including gill nets, electrofishing, and fyke nets. Length-frequency distributions were created to assess size structure in each region. Relative abundance was measured using catch per unit effort. Data analysis included a one-way ANOVA to compare Proportional Size Distribution (PSD) values and the distribution of fish sizes among regions. Chi-square …

Comparison Of Hoop Nets To Trap Nets In Sampling Panfish, Jayden R, Alsleben

Journal of Earth and Life Science

Panfish including bluegill Lepomis macrochirus and black crappie Pomoxis nigromaculatus are gamefish species of significance found in Minnesota. Hoop nets and trap nets are two types of gear that can be used to sample these fish. Fisheries managers and anglers alike are interested in the best tactics to capture panfish. The behavior of fish, including bluegill and black crappie, change throughout the sampling season and make it difficult to assume accurate representations. Trap nets have historically been adequate in sampling near shore populations, but questions surrounding the gear have allowed other options to be pursued. The objective of this study …

The Relationship Between Plant Density And Microplastic Concentration In The Water In Lake Bemidji, Mn, Arian Garcia

Journal of Earth and Life Science

Microplastics, plastic particles smaller than 5 mm, are an increasing environmental threat, particularly due to their widespread distribution and toxicity. While much research has focused on larger freshwater and marine ecosystems, the presence and impacts of microplastics in smaller inland lakes remain less understood. This study investigates the relationship between plant density and microplastic concentrations in Lake Bemidji, a smaller freshwater lake. A total of 30 water samples were collected across varying vegetation conditions, ranging from open water (0%) to 90% plant coverage. Microplastics were identified and categorized into six morphological types: fibers, fragments, films, spheres/beads, and foam. The samples …

A Sample Of Fish Communities In Beaver Ponds Of Northern Minnesota, Reed Cumberland, Rose Kuhlmann

Journal of Earth and Life Science

The North American beaver Castor canadensis is an ecosystem engineer and a keystone species to the environment. Beaver inhabit ponds and construct dams to build ponds that provide habitat for certain fish. Little information is provided on the species of fish that live in beaver ponds. The objective of this study is to sample the fish communities in beaver ponds while comparing the effectiveness of two styles of minnow traps. Twelve beaver ponds were selected in the Bemidji area to be sampled. The quantity and species caught in each style of trap were recorded to compare effectiveness of each trap …

Effects Of Round-Up On The Environment, Sandra J. Marcu

Journal of Earth and Life Science

Many people around the world have used and still currently use Roundup but are unaware of the effects it has on the environment. Roundup is a spray on application weedkiller that is widely used around the world today both residentially and commercially. It enables its user to grow a garden or a field of crops with a no-tilling approach to eliminate weeds. It is a well-known and popular choice for killing weeds that has been around since the mid 1970’s (Oca, 2017). John Franz, a Monsanto scientist discovered that glyphosate (main ingredient in Roundup) was an herbicide or weedkiller, and …

Does Depth Affect Zebra Mussel Length In Scalp Lake?, Zanden Mellen

Journal of Earth and Life Science

Since its first sighting in 1996, zebra mussels Dreissena polymorpha have been confirmed in hundreds of Minnesota lakes. Not only were they found in lakes, but they are also found in rivers too. With lack of effective treatments to impede their spread, zebra mussels continue to colonize new areas causing ecological as well as economic harm. The objective of this study was to see if there was a relationship between a zebra mussel length and the depth, they are found using shell length (mm) and depth (cm). The comparison of zebra mussel length and depth was done by performing a …

Age Class Is Not Related To Size Or Composition Of Home Ranges Among Suburban White-Tailed Deer During Parturition, Nathan D. Pyburn

Journal of Earth and Life Science

How white-tailed deer use the landscape in an urban environment can help us understand the effects of urbanization on deer populations. White-tailed deer form observable matriarchal hierarchies in studied populations. This study examines the matriarchal structure, home range size, and home range composition of 25 collared white-tailed deer within the city limits of Bemidji, MN. The results found no significant difference between age class and home range size or composition. However, movement metrics from yearling and mature age classes were more similar than the juvenile age class females. I propose this is because social acceptance between mature females was higher …

Relationship Of Utricle And Trap Door Size On Common Bladderworts Utricularia Macrorhiza, Tegwen Romportl

Journal of Earth and Life Science

The common bladderwort Utricularia macrorhiza is a carnivorous aquatic plant that captures organisms with its bladders. This study was aimed at setting the stage for future research which might determine if U. macrorhiza could be a biological method of control for invasive species. The objective of this study was to determine the relationship between utricle and trap door sizes and to gather data on the size ranges of these two morphological features. A regression analysis was used to obtain results which showed there was enough evidence to suggest that the size of bladderwort trap doors have a significant, positive relationship …

The Influence Of Flower-Microbe Interactions On Bumble Bee Behavior And Gut Microbiome Composition, Success Chiamaka Ekemezie

Graduate Theses/Dissertations

This thesis examines how microbial interactions in floral nectar and environmental variation influence bumble bee (Bombus spp.) foraging behavior and gut microbiome composition. Pollen germination experiments and behavioral assays in the lab tested whether Metschnikowia reukaufii (yeast) and Acinetobacter nectaris (bacteria) induce pollen germination and bursting in nectar and affect bee behavior subsequently. Both microbes reduced intact pollen, but bees did not alter flower preference. Furthermore, the study also assessed how floral and bee community composition shaped gut microbiome composition across six Missouri prairies. Using amplicon-sequenced fungal ITS and bacterial 16S rRNA genes, I found that fungal microbiome composition varied …

Territorial Behavior Of A Terrestrial Salamander: Effect Of Physical Stress, Residency Status, And Sex, Abigail C. Nagl

Graduate Theses/Dissertations

Environmentally induced stressors can include threats from predators and competitors. Individuals in territorial species, including the subject of this study, Southern Red-backed Salamanders, Plethodon serratus, face ongoing competitive threats, and loss of contests may be more consequential to territory owners (losing a territory) than to intruders (continuing to be without a territory). Therefore, when the threat of increased predation risk is added, residents may respond differently than intruders. Here, I tested the impact of physical stress, residency status and sex on the territorial behavior of Southern Red-backed salamanders. Territorial behavior was assessed through staged contests with same-sized and same-sexed individuals, …

Inoculating Soybean Plants At Different Growth Stages: Selecting Bradyrhizobium, Sinorhizobium, Or Both, Matthew R. Knoll

Graduate Theses/Dissertations

Soybean plants rely on nitrogen for growth, however atmospheric nitrogen (N2) is not a usable form and needs to be converted into different forms that are available to the plant. Nitrogen fixing bacteria such as rhizobia form symbiotic relationships with Soybeans in exchange for shelter and excess plant sugars. As a result, the plant can get the nitrogen it needs. There are four main genera of rhizobia that can form root nodules on Soybean including Bradyrhizobium, Sinorhizobium, Mesorhizobium, and Rhizobium. At this point, the effect that age of the host plant has on the selection of …

Restoration Of Giant River Cane (Arundinaria Gigantea) In Southwest Missouri, Lyndsey D. Rightnowar

Graduate Theses/Dissertations

Giant river cane (Arundinaria gigantea), a native bamboo species, once dominated riparian landscapes across the southeastern United States but has declined to approximately 2% of its historic range. This study evaluated restoration techniques for giant cane in southwest Missouri by examining the influence of rhizome source (putative genotype), planting type, and restoration site on restoration success. I compared two planting types: greenhouse-to-field (G2F) transplanting, where rhizomes were first propagated in the greenhouse before planting, and field-to-field (F2F) transplanting, where rhizomes were directly transplanted from source canebrakes to restoration sites. Rhizomes were collected from four existing canebrakes in Taney …

Testing The Life-History Dependence Of Dietary Restriction Effects On Oxidative Molecular Damage In Hornworms, Fahime Taheri

Masters Theses

DR and ambient temperature are two environmental factors widely implicated in shaping organismal maintenance and longevity through effects on metabolic rate and oxidative damage. This study tests whether DR and reduced body temperature independently or interactively reduce oxidative protein damage in the gut of tobacco hornworm larvae, a short-lived ectotherm whose life history may constrain typical DR responses. Larvae hatched from eggs were allocated to two feeding regimes (AL and DR) and to 20 °C and 30 °C. At a defined endpoint, guts dissected and homogenized, and analyzed for protein carbonyl content and total protein. Protein damage was expressed as …

Using Lateral Flow Assay To Assess The Prevalence Of Trachemys Hybridization, Lillian Groves

Honors Program Theses

The current study focuses on Trachemys species, which is a group of freshwater turtles found throughout the Greater Antilles. The role of studying an isolated island, such as the Dominican Republic, is significant because it serves as a way to better understand how the combined effects of species migration, mass tourism, and climate change can greatly impact isolated species. Of particular significance is how these forces interact in complex ways to reshape habitats and threaten biodiversity. Additionally, the introduction of a highly invasive species, Trachemys scripta elegans (T. scripta), in this environment pressures native species by acting as a source …

Editorial: The Development And Evolution Of Larval Nervous Systems, Oliver Vöcking, Allan Carrillo-Baltodano, Néva Meyer

Biology

Throughout their development, animals of various taxa go through different larval stages, which have evolved adaptations to interact with specific environments. Larval nervous systems in particular experience strong selection pressures since they control crucial physiological and behavioral processes, especially in taxa with planktotrophic larvae that need to acquire food. Selection pressures also can vary across life history stages if there are differences in factors such as habitat, predation avoidance, and diet. There is evidence for this in the relationship of the larval nervous system to the adult nervous system, which can vary widely between species. Understanding the specific adaptations of …

Factors Influencing The Discovery And Use Of Carrion By Vertebrate Scavengers From Human-Induced Mass-Mortality Events, Samantha J. Leivers, Michael J. Bodenchuk, Tyler A. Campbell, John M. Tomeček

Human–Wildlife Interactions

Scavengers play critical roles in ecosystem health and stability, and both biotic and abiotic factors can influence scavenger guild dynamics. Carrion is often limited both temporally and spatially on the landscape, but mass mortality events (MMEs)—in which there is an influx of carrion biomass on the landscape—may result in different scavenger community dynamics compared to when carrion is scarcely distributed. In this study, we investigated factors affecting the discovery and use of carrion by a natural, unharrassed scavenger guild during wild pig (Sus scrofa) MMEs conducted at East Foundation’s San Antonio Viejo Ranch in South Texas, USA. We …

Physiological And Genetic Studies Of Hydrotropism In The Maize Primary Root, Muyu Gu

Electronic Theses and Dissertations

No abstract provided.