Biology Commons^™

Development Of A Novel Bioink For Human Vascularized Organoids, Bradley Allen Bromet

Masters Theses

"There is a need for a model to better mimic human physiology in the clinic, so the objective was to develop a novel bioink for a 3D tissue model to study human disease and development in a dynamic 3D environment. The results from each corresponding study helped in developing a novel bioink for use in a bio printed human vascularized organoid. The bioink composed of alginate with other natural hydrogels to function as extracellular matrix and with the addition of borophosphate bioactive glasses (BPBGs) to replace growth factors, can be used with multiple cell types to bio print the proposed …

Protein Turnover Rate And Life History As An Explanation Of The Extreme Difference In Cost Of Biosynthesis In Cockroach Nymphs And Painted Lady Butterfly Larva, Kyara Nicole Holloway

Masters Theses

The cost of biosynthesis in painted lady caterpillars is far lower than that of a red runner cockroach. A promising explanation for this phenomenon is the protein turnover rate for the animal during biosynthesis and tissue maintenance. Previous research has shown that, per gram of body weight, the painted lady butterfly can synthesize a biomass using up to 15x less energy and resources than the cockroach, even under similar conditions. The resulting ratios, especially in respect to growth rate, show a wide disparity between species in such a manner that does support a protein synthesis and degradation rates as a …

Go Big Or Go Home: Divergence In Morphology And Behavior Between Island And Islet Populations Of The San Cristóbal Lava Lizard (Microlophus Bivittatus), Emilio J. Mancero

Masters Theses

Rapid divergence in body size is a well-documented phenomenon among island species, associated with macroevolutionary processes of diversification and adaptive radiation. The effect of insularity in determining larger body size as an optimal phenotype is primarily attributed to lower predation and greater intraspecific competition on islands. Our study examined interpopulation variation in morphology, social behavior and predator avoidance in Galápagos lava lizards endemic to San Cristóbal island (Microlophus bivittatus), and the nearby islet Isla Lobos. Islet populations have fewer competitors than those on the island, where native and introduced predators are abundant. We simulated interactions with predators and …

Seasonal Top-Down Effects Of Fish On Benthic Macroinvertebrates And Periphyton In A Coldwater Michigan Stream, Travis John Ellens

Masters Theses

Fish can have strong top-down effects on their prey through both direct predation and non-consumptive effects in streams. We conducted manipulative field experiments to test the strength of fish predation on benthic macroinvertebrates at the patch scale in Stegman Creek. Stegman Creek is a small (0.39 m³/s at baseflow), groundwater-fed stream in western Michigan with abundant mottled sculpin (Cottus bairdii) and brown trout (Salmo trutta) acting as benthic predators. We hypothesized that fish predation decreases macroinvertebrate density, thereby increasing periphyton biomass through a reduction in density of grazing macroinvertebrates. We placed paired predator-exclusion cages …

Examining The Restoration Potential Of Prescribed Fire And Tree Girdling Treatments On A Fire Dependent Ecosystem: Ecosystem Responses And Management Implications, Rebecca Daigle

Masters Theses

Oak savannas have greatly declined since the 1800s and management is needed to maintain these rare community types. A combination of prescribed burns and mechanical thinning are a common practice to increase forb abundance and biodiversity. This study examines the viability of another technique to thin the canopy called girdling, which was used in conjunction with low-intensity prescribed burns. Early summer prescribed burns were conducted in 2017, 2019, and 2021, while girdling treatments were implemented in 2017 and 2019. The study was conducted in Kent County, Michigan at two degraded former oak savanna communities. In 2022, we collected data to …

Consistency Is Key: Investigating Vocal Consistency In Field Sparrows, Stephanie Stanton

Masters Theses

No abstract provided.

Reintroducing Hemp (Rongony) In The Material Palette Of Madagascar: A Study On The Potential Of Hemp Clay Components And Its Impact On Social And Ecological Communities., Henintsoa Thierry Andrianambinina

Masters Theses

When mentioning the word hemp, especially in the local language of Madagascar, the literal translation does not set it apart from marijuana, as they are both called “rongony” - creating the stigma around hemp as the negative stereotype of marijuana. However, the material has been used by the ancestors of Madagascar, as well as across cultures, in its fibrous form to produce fabrication like textile goods and packaging. During colonization, the prohibition of hemp intensified, and since then, any activity related to either of these plants is prohibited and will end in severe punitive measures. This thesis explores the strengths …

Fungi In Flux | Designing Regenerative Materials And Products With Mycelium, Arvind Bhallamudi

Masters Theses

As the world grapples with the escalating crisis of climate threats and environmental degradation, this research delves into the synergistic potential of design and biology, developing safe and sustainable materials for applications in prototyping, furniture and interior design. Harnessing the power of a unique organism - fungi, the study proposes an accessible, efficient, and resilient material resource system. It utilizes local waste streams and mycelium (the vegetative part of fungi) to grow functional structures. An experimental and small-scale protocol is modeled by testing bio-fabrication and bio-printing methods. The composites' performance qualities and characteristics are evaluated through mechanical testing and a …

The Application Of Microbial Source Tracking To Aid In Site Prioritization For Remediation In Lower Michigan, John J. Hart

Masters Theses

Non-point source fecal pollution is a threat to both the environment and public health. Climate change, aging infrastructure, and intensified agricultural practices are predicted to accentuate this issue. In Michigan, due to the high instance of aging infrastructure and intensified agriculture, non-point source fecal pollution has caused many waterbodies to exceed the state standards posing a risk to recreational activities and source water. Due to this threat, there is an increased effort to identify and remediate these sources. My study focused on improving the identification of non-point source fecal pollution through a combination of culture-based and molecular fecal indicator bacteria …

Mate Recognition In Genetically Distinct Populations Of The Eastern Red-Backed Salamander (Plethodon Cinereus), Courtney Thomas

Masters Theses

Lineages that have undergone genetic divergence and subsequently experience secondary contact present fascinating situations related to the potential for reproductive isolation. Within species hybrid zones provide unique opportunities to test the strength of reproductive barriers through behavioral experiments when genetic relatedness between groups is established. Among the complex interactions that operate to maintain species boundaries, mate recognition and mate choice are two behaviors that serve to promote evolutionary independence across diverse taxonomic lineages. I explored mate recognition in genetically distinct populations of the Eastern Red-backed Salamander, Plethodon cinereus, a small, abundant, terrestrial salamander with a widespread distribution throughout northeastern United …

“Albertania” And “Egbenema”, Expanding Biodiversity In The Oculatellaceae (Cyanobacteria)., Mildred Akagha

Masters Theses

To conduct molecular studies of cyanobacteria of Lagos, Nigeria, a total of eight soil/subaerial samples were collected in Lagos State, Nigeria, and used to isolate cyanobacterial cultures that were characterized microscopically, sequenced, and phylogenetically analyzed. Within the resulting set of cultures, a number of Synechococcales were observed, particularly belonging to Oculatellaceae. “Egbenema” and two new putative species of the recently described genus Albertania were found. Both genera belong to a supported clade within the Oculatellaceae that includes Trichotorquatus and Komarkovaea. The two new putative species of Albertania, “A. egbensis” and “A. latericola”, were from the same sample, but phylogenetically were …

Species Responses To Habitat Edges And Fragmentation Per Se: A Cross Taxa Meta-Analysis, Rachel Snyder

Masters Theses

Aim We examined the scale equivalency of fragmentation effects at the patch scale and landscape scale to determine if patch level effects scale up to landscape level effects. First, we examined species responses to fragmentation effects at the patch scale and landscape scale. Second, we evaluated whether there is a difference in response between taxonomic groups and across latitudes. Finally, we analyzed the data at the level of individual species in order to determine how species respond to edge effects and fragmentation effects. Location Data for 71 studies were gathered from the BioFrag database. Studies used were located in 48 …

Climate Refugia For Neotropical Snakes: Implications Of Microhabitat Use And Diet Specialization, Consuelo Alarcon

Masters Theses

Aim: The aims of this study were to compare the locations of climate refugia and diversity patterns of the Neotropical tribe Pseudoboini and to provide critical analysis of the potential role of climatic stability and ecological specialization in the contemporary and historical distribution of this group of snakes. We expected species with narrow ecological requirements to occupy climatically stable areas, whereas generalists and arboreal species would occupy areas with more variable climate.

Location: South America

Methods: We compiled observations from the scientific literature and herpetological notes (1844-2019) with additional data from museum collections throughout South America to …

A Biodiversity Survey Of The Soil Crusts Of The Geographically Isolated San Nicholas Island, California, Usa And Description Of Species In Three Genera (Atlanticothix, Pycnacronema, Konicacronema) Previously Restricted To Brazil Using A Polyphasic Approach To Cyanobacterial Taxonomy, Brian Jusko

Masters Theses

San Nicholas Island, California, USA is a geographically-isolated island that experiences a semiarid climate and exhibits significant topographic and geologic diversity. Access to the island is restricted to the public and, as a result, only one previous study has been done on the algal biodiversity of its biological soil crusts. The previous study used morphology as the sole basis of species identification, and it was the aim of this study to corroborate and expand upon the results by including molecular data. Using 16S rRNA and 16S–23S ITS sequences and phylogenetic analyses, a diverse set of taxa were identified and are …

Wolbachia Infection In Gall Associated Insect Communities In Illinois And Indiana, Jakeb Watts

Masters Theses

Wolbachia is a maternally inherited, gram-negative bacterium and has been found to be associated with up to 60% of all insects, frequently resulting in male-killing, feminization, and cytoplasmic incompatibility in the hosts. Gall wasps and other gall-forming insects induce on various host plants abnormal tissue growths, or plant galls, with distinct morphology. They are considered as obligatory parasites to their host plant. The presence of Wolbachia infection in gall wasp populations in North America has not been extensively documented. Given the strong influence on host reproduction, not knowing Wolbachia infection in insect populations prevents the understanding of how populations are …

Environmental Dna Metabarcoding As A Tool For Fish Community Assessment In Wetlands, Eric Ludwig

Masters Theses

"Environmental DNA (eDNA) metabarcoding is a genetically based method of assessing biodiversity in aquatic environments. While the efficacy of eDNA surveys has been well documented in riverine and marine systems, it has been relatively underemployed in freshwater wetland environments. In this study, we conducted an eDNA metabarcoding survey of fish diversity and its seasonal variation in a wetland along the Mississippi River in the Missouri Bootheel. Samples were collected from both permanent and seasonal water bodies including oxbow lakes, a shallow, man-made lake, a ditch, and a slough. For each of the 28 sites in this study, three water samples …

Benthic Macroinvertebrate Pre-Assessment Of A Proposed Restoration In The Grand River, Grand Rapids, Mi, Usa, Matthew L. Bain

Masters Theses

River restoration is the dominant field of applied water resources management in the United States. Ecological improvement should be the goal of all river restorations, though many restoration projects fail to produce positive results due to limited scope or inadequate assessment methodologies. Pre-restoration, biotic data is essential for such projects as it can be paired with post-restoration data to gauge ecological outcomes. A major restoration effort is now underway in Michigan's longest river, the Grand River, where it flows through downtown Grand Rapids. The primary restoration measures will occur in-stream at local scale. We conducted a pre- restoration survey for …

Relationships Among Age, Relative Telomere Length, And Dna Methylation In Pteropus Bats, Erika E. Forest

Masters Theses

Bats are the longest-lived mammalian order relative to body mass, but questions remain about relationships among mechanisms related to aging. Relative telomere length (rTL) decreases with age in most mammals, but the relationship between age and rTL is highly variable among the few bat taxa studied to date. More recently, DNA methylation (DNAm), a type of epigenetic regulation in which methyl groups are added to cytosine-phosphate-guanine (CpG) sites across the genome, has been shown to be highly predictive of age in many species of bats. We examine the relationships among age, rTL, and DNAm in Pteropus pumilus and P. hypomelanus …

Neurogenesis And Functional Recovery In The Adult Mouse Retina Using An Alpha7 Nachr Agonist After Blast Exposure, Jake Bennett Spitsbergen

Masters Theses

Previous studies have provided evidence that eyedrop application of the selective α7 nicotinic acetylcholine receptor agonist, PNU-282987, induces neurogenesis and regeneration of retinal neurons from Müller glia in adult rodents. The objectives of this research include: 1) examination of the cellular and functional damage associated with ocular blast exposure, and 2) evaluation of structural and functional recovery post PNU-282987 treatment. Significant ocular blast damage was induced in adult mice after exposure to a single blast of 35 psi to the left eye. Blast-exposed transgenic mice expressing tdTomato Müller glia were treated daily with eyedrops containing PNU-282987 for 4 weeks following …

Influence Of Soil And Land Cover On Chronic Wasting Disease Prevalence In White-Tailed Deer And Mule Deer Across North America, Madison L. Miller

Masters Theses

Chronic wasting disease (CWD) is a fatal neurodegenerative disease that infects deer and is caused by a pathogenic prion. CWD is a concerning wildlife disease because it is incurable, potentially poses a risk to human health, and is spreading rapidly. CWD prions are transmitted both directly via bodily fluids and indirectly through environmental reservoirs such as soil. In this study, we investigated the influence of land cover and soil characteristics on CWD prevalence in white-tailed deer and mule deer. We acquired CWD prevalence data from seven North American regions and used ArcGIS to obtain land cover and soil characteristic data …

One Shell Of A Problem: Cumulative Threat Analysis Of Male Sea Turtles Indicates High Anthropogenic Threat For Migratory Individuals And Gulf Of Mexico Residents, Micah Ashford

Masters Theses

Human use of oceans has dramatically increased in the 21st century, with some of the highest rates of change found within the Gulf of Mexico and Caribbean. Sea turtles are particularly vulnerable to anthropogenic stressors in the marine environment as they make lengthy migrations between foraging and breeding sites often along coastal migration corridors. Sea turtles face severe population pressure from humans, yet little is known about how movement and threats interact specifically for male sea turtles. To better understand male sea turtle movement, and the threats they encounter within their expansive ranges, we tagged 40, adult male sea turtles …

Assessment Of Repeatability And Behavioral Syndromes In Genetically Distinct Clades Of Eastern Red-Backed Salamanders (Plethodon Cinereus), Kelsey Garner

Masters Theses

Animal personality implies limited behavioral plasticity and behavioral traits which are correlated across contexts. Correlated behaviors, sometimes referred to as behavioral syndromes, have the potential to inhibit behavioral traits from evolving independently. Limits on behavioral variation can influence a population’s ability to invade new geographic areas and exploit new niches. One way to explore such variation is to examine behavioral syndromes in genetically distinct populations of wide-ranging species that exhibit different dispersal pathways and distances. The personality-dependent dispersal syndrome suggests that certain traits, such as exploratory and risk-taking behavior, are correlated with dispersal success. The Eastern Red-backed Salamander (Plethodon …

Survey Of Diatom Periphyton Assemblages In Lake George, Joy Jackson

Masters Theses

Lake George is an oligotrophic lake that has been monitored by the International Biological Monitoring Program (IBM) since the 1960s. The 51 km long lake is separated into two deep basins, one in the south where the major stream inputs are located, and one in the north where the lake feeds the La Chute River, which empties into Lake Champlain. The two basins are separated by a shallow channel named the “Narrows.” The southern basin has experienced a higher level of development than the northern basin. The aim of this study is to characterize the diatom assemblages in the northern …

Variation In Alkaloid Composition And Sequestration In Dendrobatid Poison Frogs, Katherine R. Waters

Masters Theses

No abstract provided.

Alkaloid-Based Chemical Defenses In 11 Species Of Bufonid Poison Frogs From Brazil (Bufonidae: Melanophryniscus), Emily Staufer

Masters Theses

The term ‘poison frog’ describes members of five anuran families that are capable of sequestering lipophilic, alkaloid-based chemical defenses from their prey. Alkaloid defenses can vary widely within and among poison frog species, mostly linked to differences in availability of arthropod prey at different scales. While research has mainly focused on alkaloid variation within the dendrobatid and mantellid poison frogs, bufonid poison frogs in the genus Melanophryniscus demonstrate high inter- and intra-species alkaloid variation, and some members are capable of both sequestering dietary alkaloids and synthesizing alkaloids metabolically. However, of the 31 species of Melanophryniscus, only eight have ever had …

“Albertania” And “Egbenema”, Panding Biodiversity In The Oculatellaceae (Cyanobacteria)., Mildred Akagha

Masters Theses

To conduct molecular studies of cyanobacteria of Lagos, Nigeria, a total of eight soil/subaerial samples were collected in Lagos State, Nigeria, and used to isolate cyanobacterial cultures that were characterized microscopically, sequenced, and phylogenetically analyzed. Within the resulting set of cultures, a number of Synechococcales were observed, particularly belonging to Oculatellaceae. “Egbenema” and two new putative species of the recently described genus Albertania were found. Both genera belong to a supported clade within the Oculatellaceae that includes Trichotorquatus and Komarkovaea. The two new putative species of Albertania, “A. egbensis” and “A. latericola”, were from …

Geographic Range Size As A Predictor Of Dispersal-Dependent Behavioral Traits In Two Clades Of A Terrestrial Salamander, Teah Evers

Masters Theses

Animal movement has the potential to affect diverse processes within ecology and evolution including range expansion, gene flow, adaptation, and speciation. Two aspects of animal personality that are germane to dispersal are exploratory and aggressive behavior. These behavioral categories may represent a trade-off such that energy invested in territorial defense leaves little energy for movement and dispersal. The Eastern Red-backed Salamander (Plethodon cinereus) is a wide ranging, dispersal limited, terrestrial salamander with well documented phylogeographic divisions. I examined dispersal-relevant behavioral traits within two clades of P. cinereus with disparate geographic ranges. The Northern Clade (NC) has a range extending from …

Validation Of Edna Metabarcoding : A Comparison To Traditional Survey Methods In Ozark Streams, Veronica Marian Lee

Masters Theses

Environmental DNA (eDNA) sampling provides a method for assessing fish communities that has potential as a supplement to traditional sampling methods due to its ability to save time as well as its non-invasive nature. This is a method in which from just one sample, eDNA from multiple individual species are able to be sequenced in tandem and the resulting reads identified to describe a community. In order to evaluate this technique and its efficacy for monitoring fish community diversity, we collected water samples alongside surveys performed by the Missouri Department of Conservation sampling program in summers 2020-21. DNA were extracted …

Assessing The Short-Term Effects Of Translocation On Freshwater Mussels: Is Habitat Or Water Quality More Important?, Joshua D. Arnold

Masters Theses

Freshwater mussels (Order: Unionida) are very important to the function of aquatic ecosystems and are typically indicators of good water quality. They provide a valuable link between the water column and the benthic substrate in which they live and are a valuable food resource for many species of animals. However, most species native to North America are currently threatened with extinction, to the point that more than 70% of native freshwater mussels are listed as either threatened or endangered at the state or federal level. The cause of this decline can be attributed to historical over exploitation, habitat alteration, and …

Pedigree And Molecular Assessment Of Relatedness In A Captive Chimpanzee Population, Francesca Golus

Masters Theses

As a crucial component of biodiversity, genetic diversity contributes to variability among individuals, allowing populations of endangered species to be resilient in the face of changing environmental conditions. Zoological institutions have become a cornerstone of conservation efforts and a refuge for endangered species given threats imposed on wild populations by climate change, habitat fragmentation and degradation, and overexploitation. Chimpanzees (Pan troglodytes) are an endangered species experiencing drastic population decline in the wild, yet are common residents in zoos and wildlife sanctuaries. To sustain long-term, genetically viable populations of species of concern, zoos use studbooks and paternity testing to …