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Notes On Patagium Morphology In The Gliding Flat-Tailed House Gecko (Hemidactylus Platyurus), Amber M. Petty, Tony Gamble, Aaron H. Griffing

Biological Sciences Faculty Research and Publications

Several species of geckos have independently evolved patagia, membranous features that facilitate gliding. Detailed morphological investigations of gecko patagia have largely been limited to gliding members of the genus Gekko (formerly in the genus Ptychozoon). Herein we describe the morphology of gliding patagia of the Flat-tailed House Gecko (Hemidactylus platyurus), a species with an independent evolutionary origin of gliding patagia from Gekko and an important species for researching gliding biomechanics. We compared morphology of H. platyurus with a closely related non-gliding species, the Common House Gecko (Hemidactylus frenatus). Using external examination and histological techniques, we …

Bacillus Subtilis-Derived Peptides Disrupt Quorum Sensing And Biofilm Assembly In Multidrug-Resistant Staphylococcus Aureus, Kyle R. Leistikow, Daniel S. May, Won Se Suh, Gabriel Vargas Asensio, Adam J. Schaenzer, Cameron R. Currie, Krassimira R. Hristova

Biological Sciences Faculty Research and Publications

Multidrug-resistant Staphylococcus aureus is one of the most clinically important pathogens in the world, with infections leading to high rates of morbidity and mortality in both humans and animals. The ability of S. aureus to form biofilms protects cells from antibiotics and promotes the transfer of antibiotic resistance genes; therefore, new strategies aimed at inhibiting biofilm growth are urgently needed. Probiotic species, including Bacillus subtilis, are gaining interest as potential therapies against S. aureus for their ability to reduce S. aureus colonization and virulence. Here, we search for strains and microbially derived compounds with strong antibiofilm activity against multidrug-resistant S. …

Targeting Ocean Conservation Outcomes Through Threat Reduction, Joseph A. Turner, Malcolm Starkey, Nicholas K. Dulvy, Frank Hawkins, Louise Mair, Adeline Serckx, Thomas Brooks, Beth Polidoro, Stuart H. M. Butchart, Kent Carpenter, Minna Epps, Rima W. Jabado, Nicholas B. W. Macfarlane, Leon Bennun

Biological Sciences Faculty Publications

Nations have committed to reductions in the global rate of species extinctions through the Sustainable Development Goals 14 and 15, for ocean and terrestrial species, respectively. Biodiversity loss is worsening despite rapid growth in the number and extent of protected areas, both at sea and on land. Resolving this requires targeting the locations and actions that will deliver positive conservation outcomes for biodiversity. The Species Threat Abatement and Restoration (STAR) metric, developed by a consortium of experts, quantifies the contributions that abating threats and restoring habitats in specific places offer towards reducing extinction risk based on the IUCN Red List …

Response Of Helenium Amarum To Environmental Stressors In The Presence Of Mycorrhizal Fungi And Its Role As A Pollinator Resource, Austin Jameson, Lisa Horth

Biological Sciences Faculty Publications

Globally, climate change is causing shifts in precipitation patterns. Shifting precipitation patterns can be a stressor for many species. One species that is experiencing such stress is Helenium amarum Raf (H. Rock). H. amarum, thrives in dry upland pastures and low-lying grassy and sandy habitat in the mid-Atlantic (USA), where it persists despite storm-driven standing water. Helenium amarum is a species that is toxic to livestock and has been found outside its native range. Temperature and light impacts on germination are already known, but the role of water availability and potential ameliorating effects of mycorrhizae during water stress have …

Environmental Implications Of Modern Food Production: An Analysis For The Conscious Consumer, Jessica T. Coming

Cal Poly Humboldt theses and projects

This project explores the pathways by which agriculture affects the environment and determines which foods have the greatest climate, water, and land impacts. Agricultural effects on the environment are extensive, from loss of habitat and declines in regional biodiversity to disruption of global nutrient cycles and climate change. Global food production accounts for 26-34% of annual anthropogenic greenhouse gas emissions, makes up 38-46% of habitable land, and is responsible for 70% of freshwater extraction. The effect of agriculture on the environment is most significantly dictated by what type of food is being produced. Animal-based food products consistently have the highest …

Characterization Of Host Cell Specific Interactions During Spotted Fever Group Rickettsiae Infection, Emerson Towey

Graduate Theses, Dissertations, and Problem Reports (ETD)

Vector-borne diseases have been increasing over the past few years due to changes in climate and disturbances in the vectors’ natural environment. To mitigate the risks of these diseases, it is necessary to understand pathogen biology and how it interacts with a host to cause disease. Here we focus our attention on the tick-borne pathogen, Rickettsia rickettsii. R. rickettsii is a member of the spotted fever group (SFG) Rickettsiae and is the etiological agent of Rocky Mountain spotted fever (RMSF), a fatal human disease that is lacking an effective vaccine. Members of the bacterial genus Rickettsia are obligate intracellular endoparasites …

Long Term Trends In Mortality Rates Of A Smallmouth Bass Population, Caleb D. Anderson

Journal of Earth and Life Science

Smallmouth bass Micropterus dolomieu are known as a popular sport fish for anglers. When a known smallmouth bass fishery appears to have a dwindling population, it raises questions about the population health. A common indicator of the health of the population is the mortality rate. By comparing mortality, conclusions can be made on whether smallmouth bass are dying at a different rate in the system over time. Therefore, the objective of this study was to see if there had been a significant change in smallmouth bass mortality over a span of thirty years in Round Lake (DOW:010204), Aitkin County, Minnesota. …

Relationship Between Northern Pike And Walleye Cpue In Minnesota Lakes, Simon Oslund

Journal of Earth and Life Science

Northern pike Esox lucius and walleye Sander vitreus are both top predators in freshwater systems. Due to their predatorial nature, high populations of one species can prohibit populations of the other species from thriving, specifically northern pike foraging on walleye. This information is tracked by the Minnesota Department of Natural Resources through catch per unit effort (CPUE). CPUE data was gathered for all lakes in Beltrami County, Minnesota, and a regression analysis was done to test for a relationship between pike and walleye. It was found that the relationship between northern pike and walleye CPUE was significant (P = 0.02). …

The Effects Of Length, Weight, Age, And Gender On Mercury Concentrations In Burbot In North-Central Minnesota Lakes, Liam Hanley

Journal of Earth and Life Science

Burbot Lota lota in north-central Minnesota lakes have the potential to reach large sizes and consume large volumes of prey. This caveat may make burbot susceptible to higher rates of biocontamination, bioaccumulation and biomagnification. The objective of this study was to determine how changes in age, length, gender, weight, and lake affect total mercury concentrations in burbot. In this experiment 28 burbot were angled from three lakes: Cass (n = 17), Winnibigoshish (n = 4), and Bad Medicine (n = 7). Then tissue samples were taken from each fish and were lyophilized and homogenized. Homogenized tissue samples were analyzed by …

Relationship Between Fishing Hours And Number Of Fish Harvested From Upper Red Lake, Dylan Ohlenkamp

Journal of Earth and Life Science

Total hours fishermen spend fishing and total amount of fish harvested per year are some of the most important pieces of knowledge gained from creel surveys. They provide crucial information that assesses fisheries mortality and pressure. MN DNR uses their results from creel surveys to improve or impose regulations, and to maintain healthy fisheries. Based on results from similar studies, there is expected to be a positive relationship between hours fished and fish harvested. To determine the relationship between these two variables on Upper Red Lake, data from two years were selected when the variables were at their highest and …

A Guide To Otoliths Of Minnesota Fishes, Baylor J. Short

Journal of Earth and Life Science

Investigations into the diet patterns of piscivores can provide crucial information on predator-prey relationships, population dynamics, and responses to changing ecosystems. However, digestive processes often remove or alter physical characteristics that are traditionally used to identify consumed fish. This problem has been addressed to some degree with advances in molecular technologies, although these methods can be costly and require specific training and equipment to do so. In contrast, bony structures such as otoliths, vertebrae, cleithra, and others frequently have morphologies that are unique among families, genera, and species. Because these structures are resistant to digestion, they can be used to …

The Effect Of Triaenophorus Crassus On The Condition Of Coregonus Artedi, Alexander Surma

Journal of Earth and Life Science

Cisco Coregonus artedi is, historically, the largest commercial fishery in the Great Lakes. The species is also important to commercial and recreational fisheries in inland lakes. Tapeworm Triaenophorus crassus larvae embed themselves into the flesh of Ciscoes, rendering the fish unmarketable to humans. Triaenophorus crassus is common in inland waters such as Leech Lake and Cass Lake, MN. One Canadian researcher has suggested that the parasite negatively affects the growth and weight of Ciscoes. Poor condition can reduce fecundity, leading to lower recruitment rates. This would mean a detrimental impact on not only individual fish, but the health of …

Cd46 Interaction With Adenovirus Type 64, A Causative Agent For Viral Pink Eye, Hanglin (Henry) Zhu

Honors Theses

Human adenovirus type 64 (Ad64) is a causative agent of contagious viral pink eye. We do not understand why Ad64 causes eye infections. One likely reason is the presence of a receptor molecule on the exposed surface of eye cells, but not other cells. Ad64 binds to a protein called CD46 on the cell surface. We aim to visualize how CD46 binds to the surface of Ad64. I mixed the extracellular portion of CD46 with purified Ad64 virus, then visualized it using negative stain transmission electron microscopy. In order to gain insight into how the virus binds CD46, we used …

Quantifying The Ecological Effects Of Salix Fragilis On Riparian Habitat In Kittitas County, Washington, Landon Shaffer

All Master's Theses

Invasive species threaten plant community structure and function globally. Riparian areas, the zone near streams where water influences vegetation, are especially sensitive to invasive species colonization, suffering large-scale shifts in community composition. Salix fragilis (crack willow) is a nonnative riparian species abundant in the lower elevation tributaries of central Washington. Some speculate whether this willow should be listed as invasive in Washington, despite a lack of regional supporting evidence. I studied riparian communities dominated by either S. fragilis or native species in the Kittitas Valley and measured biodiversity, quantified differences in solar attenuation, and compared leaf decomposition rates to learn …

Mortality Index Of Drosophila Melanogaster, Following Traumatic Brain Injury, Megan N. Ashworth

Graduate Student Dissertations, Theses, Capstones, and Portfolios

Traumatic brain injuries (TBI) are associated with immediate and long-term consequences that can be divided into primary and secondary injuries. A primary injury results due to the direct damage inflicted on the brain by the hit, whereas a secondary injury takes more time to manifest due to the cascade of molecular events that lead to cellular damage and death within the brain. This study analyzes mortality as a secondary injury following traumatic brain injury in the presence of a human neurodegenerative genetic risk factor, APOE ε4. The High Impact Trauma (HIT) device developed by Katzenberger et al. (2013) was utilized …

Parasite Prevalence And Innate Immunity In Mud And Musk Turtles, Nicole Beckett

Honors Program Theses

Turtles are being infected by both ectoparasites (typically leeches) and endoparasites (typically blood parasites). It is unknown what the parasite intensity is of wild Central Floridian turtles is, and what effect this parasite load has on them. In order to determine these factors wild turtles (Sternotherus odoratus, Kinosternon baurii, and Kinosternon subrubrum) were caught from two locations, Mead Botanical Gardens, and Lake Virginia. Hoop traps were used to catch the turtles, which were then sampled and released. Captured turtles went through a series of measurements as well as a blood draw before release. Blood parasite levels were taken from the …

Pcb Remediation In Transitional Floodplain Forests Along The Housatonic River, Soleil Laurin

Scripps Senior Theses

Human development affects natural environments in more ways than climate change, from the introduction of nonnative species and deforestation to pollution and urbanization. This is a case study examining the effects of PCB remediation on transitional floodplain forest along the Housatonic River in Western Massachusetts. The Housatonic River had previously been contaminated with PCBs and portions had been remediated. This study aims to determine the effects this remediation had on transitional floodplain forests, as well as provide a preliminary biodiversity assessment for sites that are planned to be remediated of PCBs by the Environmental Protection Agency. The study was carried …

Genetic Diversity Of Paxistima Canbyi A. Gray: Conserving A Rare Plant Species Endemic To The Eastern United States, Isaac Buabeng

Master’s Theses

Premise: The glacial cycles of the Pleistocene period likely had a profound impact on the genetic diversity and phylogeographic patterns of numerous plant taxa in North America. However, the genetic diversity of rare, limestone-endemic woody species has not been highlighted. This study assesses genetic diversity in Paxistima canbyi A. Gray (Canby’s mountain lover or rat stripper), a rare limestone endemic small woody plant.

Methods: We investigated the genetic diversity of P. canbyi using genomic Single Nucleotide Polymorphism (SNP) data from 165 individuals from 14 populations sampled from across the entire range distribution. We first; de novo assembled the SNP …

Localization And Quantification Of Atpase, Ca2+ Transporting, Plasma Membrane 2 (Atp2b2) In The Developing Euthyroid And Hypothyroid Cochlea, Emily Gregersen

All Graduate Theses, Dissertations, and Other Capstone Projects

Thyroid hormone (TH) is essential for auditory system development. Proper auditory function requires remodeling and transformation of cochlear structures during a critical developmental period. In rodent models, low TH during this timeframe delays remodeling and impacts ion channel function required for hearing to occur. TH receptors are ligand-dependent transcription factors that regulate expression of genes. Considering this, auditory deficits observed in hypothyroidism are thought to be largely the result of altered expression of specific TH receptor target genes. TH is reported to impact calcium signaling in several tissues, but whether regulators of calcium signaling are altered following developmental hypothyroidism is …

Compliance And Roughness In Relation To Gecko Locomotion, Brooklynn Campbell

Williams Honors College, Honors Research Projects

Geckos move efficiently through a variety of substrates, from swaying branches to wooden fences to the sides of structures. Previous studies have studied locomotion and adhesion on manmade and rough substrates; however, the work is limited when discussing locomotion and adhesion as a relationship of compliance and roughness. Ease of movement was quantified by speed, under the assumption that the faster a gecko moves, the easier it is for the gecko to cross the substrate. Gehyra oceanica geckos from Moorea, French Polynesia were tested on substrates varying in compliance and roughness with four different treatments in total. Compliance, roughness, and …

Microglia Regulate Light Evoked Retinal Responses In The Zebrafish Retina., Brittney Moore

Williams Honors College, Honors Research Projects

The primary goal of the project is to investigate the role of the interferon regulatory factor 9 (irf8) gene in the retinal function of zebrafish. My research aims to examine and compare the retinal responses of two subject groups: wildtype zebrafish and zebrafish with the irf8 gene knocked out. This project seeks to determine if irf8 knockout zebrafish lose visual system functionality before experiencing changes in retinal morphology. The primary technique to answer this research question is the electroretinogram, a commonly used method to examine retinal function. The final outcome of this project will be a scientific paper describing the …

The Effects Of Ethanol Exposure On Glucose And Lactate Levels In Crayfish, Mackenzie Kirwan

Williams Honors College, Honors Research Projects

The goal of the project is to investigate and determine the effects of sunlight exposure and hormone levels. The circadian rhyth, which is heavily influenced by sunlight, not only affects the amount of sleep someone achieves, but is also related to behavior and mood, and heavily relies on the body’s hormones for proper regulation. The hormones that are prevelant to the circadian rhythm, and which will be studied in this experiment are cortisol, serotonin and melatonin. In this experiment, these three hormones will be extracted prior to alterations of light exposure. Animal test subjects will then undergo treatment of light …

Snake Translocation Policies And Practices Within The United States, Robin E. Bedard, Megan Rottenborn, Emily Taylor

Human–Wildlife Interactions

Human–wildlife conflict with nuisance snakes (Serpentes) is rapidly increasing with human population growth and development rates. Translocation of nuisance snakes has become a widespread practice, aided by social media pages connecting people to volunteer and for-profit snake translocators. However, translocators often struggle to find information and resources from wildlife agencies about the policies required, and some may unintentionally use translocation procedures that disregard the health and survival of the snakes. The goals of this study were to (1) obtain data on policies, permitting, and training required for translocating nuisance snakes in each U.S. state that has snakes and (2) compare …