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Effects Of Anthropogenic Noise On The Provisioning Behavior Of Western Bluebirds And Artificial Light At Night On Nestling Development, Kerstin H. Ozkan

Master's Theses

Sensory environments are rapidly changing due to increased human activity in urban and non-urban areas alike. For instance, background sounds can interfere with parent-offspring communication and mask cues reflective of predation risk, resulting in elevated vigilance at the cost of provisioning. In chapter 1, we studied nestling provisioning behavior among Western Bluebirds (Sialia mexicana) in response to short-term (1 hr) and long-term (continuous exposure throughout nesting period) noise exposure. Provisioning rates were lower at nests exposed to short-term experimental traffic noise compared to exposure to ambient background sounds. Trial order strongly influenced provisioning behavior, with the decline in …

Coralai: Emergent Ecosystems Of Neural Cellular Automata, Aidan A. Barbieux, Aidan A. Barbieux

Master's Theses

Artificial intelligence has traditionally been approached through centralized architectures and optimization of specific metrics on large datasets. However, the frontiers of fields spanning cognitive science, biology, physics, and computer science suggest that intelligence is better understood as a multi-scale, decentralized, emergent phenomenon. As such, scaling up approaches that mirror the natural world may be one of the next big advances in AI. This thesis presents Coralai, a framework for efficiently simulating the emergence of diverse artificial life ecosystems integrated with modular physics. The key innovations of Coralai include: 1) Hosting diverse Neural Cellular Automata organisms in the same simulation that …

Ungrading: Reflections Through A Feminist Pedagogical Lens, Erin M. Eggleston, Shelby Kimmel

Feminist Pedagogy

Ungrading is a pedagogical approach in which no grades are given on any assignments. Instead, students are provided with many opportunities to submit work and gain feedback. The goal is to shift student focus from achieving a grade to growth as a learner and a person. As instructors, our ungrading approach utilized personalized learning plans, checkpoint reflections, and student-professor learning conferences to put agency in the hands of our students. We employed this method in upper-level biology and computer science courses and provide critical reflections here regarding our experiences and the connections between this approach and feminist STEM pedagogy tenets. …

Feminist Biology: Towards Gender Equity In The Biology Curriculum, Nicole Danos, Carla Y. Bonilla, Sofia Leung

Feminist Pedagogy

The current curriculum in STEM is a product of historically unequal representation of genders in the science community. As a result, most attention has been given to male biology, creating a knowledge gap that has affected our social and political perspectives, such as an underinvestment in women’s health research. Feminist biology seeks to provide equal time and weight to the impact of sex as a biological factor, using inclusive definitions of biological sex that go beyond the male/female binary. Feminist pedagogy is a method of teaching that involves engaged learning and reflection in order to create a community of learners …

Deep Ocean Vehicle Applications And Modifications, Nichole "Nikki" T. Arm

Master's Theses

This project had two primary goals: (1) to explore opportunities to further a deep-ocean vehicle’s reach using alternative pressure spheres, and (2) to implement an existing deep-ocean vehicle (lander) in active scientific research.

I gained a greater understanding of the limitations and design choices made for existing pressure spheres using Finite Element Analysis (FEA). My simplified FEA model predicted sphere failure for the existing 30% Fiber Glass 70% Nylon injection molded spheres at an external pressure of 3,954psi or 2,690m ocean-depth (only a 7.38% error compared to the tested minimum failure depth), so I determined it a valid model. I …

Evaluation Of Facilitation On Translocation Outcomes For San Joaquin Antelope Squirrel In The Carrizo Plain, California, Patrick R. Anderson

Master's Theses

In arid and semi-arid environments, burrowing mammals play a key role in increasing landscape heterogeneity through facilitative species interactions. The loss of burrowing mammal populations can consequently lead to negative effects cascading through the ecosystem. It is critical to understand these facilitative interactions for conservation and management. Understanding facilitative interactions may improve wildlife management tools, like translocation, which is often not very successful. To investigate the importance of burrow facilitation on San Joaquin antelope squirrel (Ammospermophilus nelsoni; SJAS) translocation success, I designed a natural experiment with a burrowing facilitator, the giant kangaroo rat (Dipodomys ingens; GKR). I …

Book Review: Elizabeth Wilson's Gut Feminism, İlkan C. İpekçi̇ Ph.D. Candidate

Feminist Pedagogy

No abstract provided.

Mate Choice And Sexual Conflict In A Livebearing Fish, Julia C. Kasper

Master's Theses

Eavesdropping occurs when a receiver extracts information from an interaction without directly engaging with the signaler. Eavesdropping has been shown to be an effective way of evaluating the quality of potential mates and their abilities in male-male competition, without having to directly interact with them, thereby reducing energy costs and mating harassment. Girardinus metallicus is a livebearing poeciliid fish endemic to Cuba whose mating system is dominated by mating harassment in the form of sneak copulations, persistent displaying, and male-male aggression. G. metallicus has a male specific polymorphism in both melanin coloration and behavior. Males with melanin coloration are known …

Mountain Lion Resource Selection In The California Central Coast: Modeling Habitat Suitability For A Large Carnivore In A Rapidly Changing Environment, Megan Elizabeth O'Connor

Master's Theses

Land use conversion toward agriculture such as orchards and vineyards can have severe negative impacts on habitat and wildlife, particularly large carnivores, globally through habitat fragmentation and loss. The mountain lion (Puma concolor) population in the California Central Coast is thought to provide “stepping-stone” connectivity between several severely genetically compromised coastal populations throughout the Santa Cruz Mountains and several mountain ranges in Southern California; however, the California Central Coast is one of the fastest-developing regions of California with little protection against future land use conversion. Conserving areas of and corridors between high-quality mountain lion habitat through conservation easements …

Southern Sea Otter (Enhydra Lutris Nereis) Fur Morphology, Thermal Function, And Buoyancy Across Ontogeny, Kate Riordan

Master's Theses

Sea otters (Enhydra lutris) have the densest fur of any animal, and the hairs function to trap a layer of air that is used for insulation. When a sea otter is born, it has a natal pelage (baby fur), and sea otters eventually molt that fur and replace it with a pelt resembling the adult fur. Sea otter fur is composed of 3 types of hairs: underhairs, intermediate hairs, and guard hairs. Sea otters are more susceptible to the negative effects of oiling from oil spills compared to other marine mammal species because they solely rely on fur …

Effects Of Intertidal Position On The Response To Oxygen And Desiccation Stress In The Common Acorn Barnacle, Balanus Glandula, Megan M. Dotterweich

Master's Theses

Sessile invertebrates in the rocky intertidal experience intermittent periods of air exposure due to tidal flux, presenting risks of temperature extremes, hypoxia, nutrient limitation, and most dangerously, desiccation. Microscale variation in severity and frequency of these risks is widely dependent on vertical position within the intertidal zone. Common acorn barnacles (Balanus glandula) have a wide vertical distribution in the intertidal, creating large differences in microhabitat between the highest and lowest individuals in the population. This study set out to explore whether tidal position dependent differences exist in the response to oxygen and desiccation stress in B. glandula. …

Food For Thought: The Effects Of Feeding On Neurogenesis In The Ball Python, Python Regius, Hannah F. Bow

Master's Theses

Pythons are a well-studied model of postprandial physiological plasticity. Consuming a meal has been shown by past work to evoke a suite of physiological changes in pythons and elicit one of the largest documented increases in post-feeding metabolic rates relative to resting values. However, little is known about how this plasticity manifests in the brains of ball pythons, Python regius. Previous work using the cell-birth marker 5-bromo-12’-deoxyuridine (BrdU) has shown that cell proliferation in the python brain increases six days following meal consumption. This study aimed to confirm these findings and build on them in the long term by …

Psf Sampling In Fluorescence Image Deconvolution, Eric A. Inman

Master's Theses

All microscope imaging is largely affected by inherent resolution limitations because of out-of-focus light and diffraction effects. The traditional approach to restoring the image resolution is to use a deconvolution algorithm to “invert” the effect of convolving the volume with the point spread function. However, these algorithms fall short in several areas such as noise amplification and stopping criterion. In this paper, we try to reconstruct an explicit volumetric representation of the fluorescence density in the sample and fit a neural network to the target z-stack to properly minimize a reconstruction cost function for an optimal result. Additionally, we do …

Functionality Of The Gracilis Collateral Is Impaired Following Arteriogenesis And Cell Transplantation, Ada A. Tadeo

Biomedical Engineering

Peripheral Arterial Disease involves narrowed arteries, reducing blood flow to limbs. Increasing blood flow to those extremities is possible by redirecting the blood to flow through natural bypasses (i.e. collateral arteries), which can enlarge via arteriogenesis to maintain blood supply once the prominent arteries have become occluded. This study aims to investigate how arteriogenesis affects collateral function, if myoblast transplantation can stimulate collateral growth, and how that in turn may affect collateral function. Femoral artery ligation was performed to mimic the blockage that occurs in patients with ischemic diseases on lean mice and mice with diet induced obesity (DIO). A …

Biomass Estimation Of Marine Biofilms On Plastic Surfaces, Kian Banihashemi, Fernando Javier Gil

Biological Sciences

Plastics have become a major source of marine pollution, which threatens food safety and quality, human health, and marine ecosystems. Due to the drastic negative effects of plastics in a marine environment, alternative biodegradable plastics are being generated that are more eco-friendly and have less environmental impact. Though some of these plastics are known to biodegrade, the process of degradation for bioplastics has not been heavily studied in a marine environment. This pilot project sought to both quantify the process of biodegradation and compare across different methods for effectiveness of biomass estimation, which serves as an indicator of biodegradation. Plastics …

Assessing Black Rat Population Abundance And Persistence At The Oceano Dunes State Vehicular Recreation Area, Mars Lu, Julia Kristina Perez

Biological Sciences

The black rat, Rattus rattus, is considered one of the most destructive and widespread invasive species around the world, with the ability to damage crops, kill native species, and spread disease. The Oceano Dunes State Vehicular Recreation Area (ODSVRA) is home to numerous at-risk species such as the Western Snowy plovers (Charadrius nivosus nivosus) and California Least Tern (Sternula antillarum browni). Black rats have been detected at the ODSVRA in studies conducted in 2015 and 2018, and may be a potential threat to nesting seabirds like the plover and the tern. In addition, they may …

Understanding Rare Species In California: An Assessment Of Camatta Canyon Amole (Hooveria Purpurea Var. Reducta) And A Meta-Analysis Of California Rare Plants In Literature, Kieran N. Althaus

Master's Theses

California is currently in the midst of a biodiversity crisis. There are approximately 5,000 native species of plants in California, a quarter of which are considered rare. Determining threats to these rare plants is often times difficult. Despite California's botanical resources, we still know very little about much of California’s rare plants. San Luis Obispo County is home to 2,000 of California’s native plant taxa, one- third of which are rare or endemic to the county. These species are of great local and environmental concern.

In Chapter 1, we attempted to assess the impact of non native species on a …

Seed Longevity And Climatic Tolerance Of San Joaquin Wooly-Threads (Monolopia Congdonii; Asteraceae) An Endangered Plant From The San Joaquin Desert, California, Paul Excoffier

Master's Theses

San Joaquin wooly-threads (Monolopia congdonii; Asteraceae) is a federally-listed, endangered annual plant species from the desert areas of the San Joaquin Valley. Its limited range puts it at risk of extinction if the climate changes in such a way as to hinder its growth and reproduction. The primary aims of the study were to 1) determine how long-lived the seeds of the M. congdonii are, a key determinant of survival of desert annual plant populations through long droughts and 2) determine how severely hotter, drier conditions impact the ability of emerged plants to grow and reproduce. Secondarily, I …

Rapid Warming Events In A Small Coastal Upwelling Embayment, Tatjana E. Ellis

Physics

Temperature variability in the nearshore coastal ocean influences various biological processes and can drive changes in biodiversity and habitat range. Despite recent progress, there are still significant gaps in the understanding of drivers of temperature variability in upwelling bays, particularly at higher frequencies. In this study, we analyzed a decade of nearshore temperature measurements both inside and outside a small coastal embayment located in central California [San Luis Obispo (SLO) bay], as well as temperature data from satellites, to characterize rapid warming events. We found that rapid warming events, defined using rates of temperature change across different thresholds, occurred more …

Occupancy Modeling Of Western Monarch Thanksgiving Counts: Negative Impacts Of Incomplete Resurveys And Uneven Sampling Efforts, Keegan M. Mclean

Biological Sciences

Western monarch butterflies (sp. Danaus plexippus) are undergoing a severe decline that rivals those occurring among insects across the globe. Despite the estimation of population abundance, growth rates, and extinction probabilities, no analyses have investigated spatiotemporal patterns of decline in the western monarch population. I performed occupancy modeling of Western Monarch Thanksgiving Count (WMTC) data. The data was constrained spatially and temporally, with sites grouped into occupancy bins by latitude and year. Occupancy probabilities (psi) were estimated for each intersection of a latitude and time bin and detection probabilities (p) were estimated for each time bin. Psi increased slightly …

Comparative Effects Of Chemical And Physical Sunscreen On Fertilization Of Purple Sea Urchins (Strongylocentrotus Purpuratus), Marilla Lippert, Maurice Codespoti Goodman, Nikki Adams

Biological Sciences

Organic compound-based “chemical” sunscreens dominate the commercial sunscreen market, but recent research has revealed the ingredients of these products are detrimental to the health of marine organisms. This revelation has led to increased popularity of mineral-based “physical” sunscreens, primarily containing zinc-oxide (ZnO), as environmentally safe alternatives. While they are marketed as environmentally safe, these claims are largely untested, and it is important to consider potential effects of ZnO-based sunscreens on the development of marine organisms. Though Zn is a necessary micronutrient in the ocean, excess Zn is released into marine environments from anthropogenic sources has negative effects on marine life. …

Study Of Plants Used Against Infections By California Native American Tribes, Maria J. Rojas

Master's Theses

The objectives of this research were to evaluate the antibacterial activity and to determine the chemical composition of a list of medicinal plants used by Native Americans in California. Artemisia californica, Mimulus aurantiacus, Equisetum telmateia, Equisetum hyemale, and Marah fabacea were selected from a list of plants reported as having been used for ailments related to infections by tribes located in California. The extracts obtained through steam distillation from E. telmateia, E. hyemale and M. fabacea were assayed for in vitro antibacterial activity against 16 Gram-negative and 6 Gram-positive bacteria using disk diffusion assays and measuring the diameters of inhibition …

Sensory Stressors Impact Species Responses Across Local And Continental Scales, Ashley A. Wilson

Master's Theses

Pervasive growth in industrialization and advances in technology now exposes much of the world to anthropogenic night light and noise (ANLN), which pose a global environmental challenge in terrestrial environments. An estimated one-tenth of the planet’s land area experiences artificial light at night — and that rises to 23% if skyglow is included. Moreover, anthropogenic noise is associated with urban development and transportation networks, as the ecological impact of roads alone is estimated to affect one-fifth of the total land cover of the United States and is increasing in space and intensity. Existing research involving impacts of light or noise …

Transgenerational Plasticity Causes Differences In Uv-Tolerance Of Intertidal And Subtidal Populations Of The Purple Sea Urchin, Strongylocentrotus Purpuratus, Yareli Alvarez, Nikki L. Adams

Master's Theses

Planktonic larvae of marine organisms are increasingly being exposed and required to respond to a changing physical environment. Adult sea urchins occupy both intertidal and subtidal waters and broadcast spawn gametes into the water column to contend with variable physical conditions. To answer how populations of invertebrates residing at different depths adequately prepare their offspring to cope with different levels of ultraviolet radiation (UVR), we collected adult purple sea urchins, Strongylocentrotus purpuratus, from four sites (two intertidal and two subtidal (~15 m deep)) on the central coast of CA to compare UV tolerance in offspring. Our measurements of UVA …

Feeling Out Your Food: A Histological Analysis Of The Whisker System In Seals, Cameron Cooper

Master's Theses

The vibrissal (whisker) system is present in nearly all mammals and is especially important in deep-diving mammals. Pinnipeds (seals, sea lions, and walruses) have highly sensitive whiskers that are used to follow hydrodynamic trails created by their swimming prey. Each pinniped vibrissa is surrounded by a tripartite blood sinus system composed of an upper cavernous sinus (UCS), a ring sinus (RS), and a lower cavernous sinus (LCS). The UCS has been hypothesized to play a thermoregulatory role, insulating temperature sensitive mechanoreceptors located within the vibrissal follicle. The aim of this study was to examine this hypothesis by measuring and comparing …

Pismo Clams (Tivela Stultorum) In Califorina: Population Status, Habitat Associations, Reproduction, And Growth, Alexandria R. Marquardt

Master's Theses

Marine shellfish play a vital role in intertidal ecosystems and coastal communities, but many of these fisheries are small-scale and lack the necessary monitoring to ensure long-term sustainability. Effective management often requires information on key demographic parameters, such as population status, reproduction and growth. Pismo clams (Tivela stultorum) are a culturally important and iconic species in California, which supported a thriving commercial and recreational fishery throughout much of the 1900’s. However, Pismo clam populations have declined statewide in recent decades and are attributed to human harvest and predation by California sea otters (Enhydra lutris); However, no …

Seasonal And Interannual Variability Of Phytoplankton Abundance And Community Composition On The Central Coast Of California, Alex Barth, Ryan K. Walter, Ian C. Robbins, Alexis Pasulka

Physics

Variations in the abundance and composition of phytoplankton greatly impact ecosystem structure and function. Within the California Current System (CCS), phytoplankton community structure is tightly coupled to seasonal variability in wind-driven coastal upwelling, a process that drives changes in coastal water temperatures and nutrient concentrations. Based on approximately a decade (2008-2018) of weekly phytoplankton measurements, this study provides the first characterization of the seasonal and interannual variability of phytoplankton abundance and composition in San Luis Obispo (SLO) Bay, an understudied region within the CCS. Overall, the seasonality of phytoplankton in SLO Bay mirrored that of the larger CCS; diatoms dominated …

Thermal Ecology Of The Federally Endangered Blunt-Nosed Leopard Lizard, Kathleen N. Ivey

Master's Theses

Recognizing how climate change will impact populations can aid in making decisions about approaches for conservation of endangered species. The Blunt-nosed Leopard Lizard (Gambelia sila) is a federally endangered species that, despite protection, remains in extremely arid, hot areas and may be at risk of extirpation due to climate change. We collected data on the field-active body temperatures, preferred body temperatures, and upper thermal tolerance of G. sila. We then described available thermal habitat using biophysical models, which allowed us to (1) describe patterns in lizard body temperatures, microhabitat temperatures, and lizard microhabitat use, (2) quantify the …

Heavy Metal Dissolution Mechanisms From Electrical Industrial Sludge, Viraj Gunarathne, Anushka Upamali Rajapaksha, Meththika Vithanage, Nadeesh Adassooriya, Asitha Cooray, Sudantha Liyanage, Bandunee Athapattu, Nishanta Rajakaruna, Avanthi Deshani Igalavithana, Deyi Hou, Daniel S. Alessi, Yong Sik Ok

Biological Sciences

In this paper, we investigate the release of heavy metals from sludge produced from an electrical industry using both organic and inorganic acids. Single and sequential extractions were conducted to assess heavy metals in different phases of the sludge. Metal release from sludge was investigated in the presence of three inorganic acids (nitric, sulfuric, and phosphoric) and three organic acids (acetic, malic, and citric) at concentrations ranging from 0.1 to 2.0 mol L−1. Sequential extraction indicated the presence of Cu primarily in the carbonate fraction, Pb in the residual fraction, and Ni in the FeMn oxide fraction. The cumulative release …

Evaluation Of Pheromone Mating Disruption For California Red Scale Control In Commercial California Citrus, Joel Timothy Leonard

Master's Theses

California red scale (CRS), Aonidella aurantii, is an increasingly injurious insect pest for the California citrus industry due to insecticide resistance, changing weather patterns, and shifting trade regulations. The presence of the insect on fruit, damages the rind of the fruit and high populations can cause dieback of branches as well as lower yields. Pheromone mating disruption of CRS has the potential to alleviate population control concerns and reduce insecticide use. The efficacy of the pheromone mating disruption technique for pest management of CRS was determined using the products CheckMate® CRS and Semios CRS Plus. CheckMate® CRS was evaluated …