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Master's Theses

California Polytechnic State University, San Luis Obispo

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Full-Text Articles in Biology

Effects Of Anthropogenic Noise On The Provisioning Behavior Of Western Bluebirds And Artificial Light At Night On Nestling Development, Kerstin H. Ozkan Mar 2024

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 Mar 2024

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 …


Deep Ocean Vehicle Applications And Modifications, Nichole "Nikki" T. Arm Dec 2023

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 Dec 2023

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 …


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 Aug 2023

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 …


Mate Choice And Sexual Conflict In A Livebearing Fish, Julia C. Kasper Aug 2023

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 …


Effects Of Intertidal Position On The Response To Oxygen And Desiccation Stress In The Common Acorn Barnacle, Balanus Glandula, Megan M. Dotterweich Jun 2023

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 Jun 2023

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 …


Southern Sea Otter (Enhydra Lutris Nereis) Fur Morphology, Thermal Function, And Buoyancy Across Ontogeny, Kate Riordan Jun 2023

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 …


Psf Sampling In Fluorescence Image Deconvolution, Eric A. Inman Mar 2023

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 …


Seed Longevity And Climatic Tolerance Of San Joaquin Wooly-Threads (Monolopia Congdonii; Asteraceae) An Endangered Plant From The San Joaquin Desert, California, Paul Excoffier Jun 2022

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 …


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 Jun 2022

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 …


Study Of Plants Used Against Infections By California Native American Tribes, Maria J. Rojas Dec 2020

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 Sep 2020

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 Sep 2020

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 Jul 2020

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 May 2020

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 …


Thermal Ecology Of The Federally Endangered Blunt-Nosed Leopard Lizard, Kathleen N. Ivey Mar 2020

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 …


Evaluation Of Pheromone Mating Disruption For California Red Scale Control In Commercial California Citrus, Joel Timothy Leonard Dec 2019

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 …


Effects Of Intertidal Position On Metabolism And Behavior In The Acorn Barnacle, Balanus Glandula, Kali Horn Nov 2019

Effects Of Intertidal Position On Metabolism And Behavior In The Acorn Barnacle, Balanus Glandula, Kali Horn

Master's Theses

The intertidal zone is characterized by persistent, tidally-driven fluctuations in both abiotic (e.g., temperature, [O2], salinity) and biotic (e.g., food availability, predation) conditions, which makes this a very physiologically challenging habitat for resident organisms. The magnitude and degree of variability of these environmental stressors differs between intertidal zones, with the most extreme physiological stress often being experienced by organisms in the high intertidal. Given that many of the fluctuating conditions in this environment are primary drivers of metabolic rate (e.g., temperature, [O2], food availability), we hypothesized that sessile conspecifics residing in different tidal zones would exhibit …


Development Of A Prolyl Endopeptidase Expression System In Lactobacillus Reuteri To Reduce The Clinical Manifestation Of Celiac Disease, Kara Lynn Jew Jul 2019

Development Of A Prolyl Endopeptidase Expression System In Lactobacillus Reuteri To Reduce The Clinical Manifestation Of Celiac Disease, Kara Lynn Jew

Master's Theses

Celiac Disease (CD) is an autoimmune disorder that emerges due to the ingestion of gluten, a protein found in a variety of common grains such as wheat, rye, and barley. Approximately 1 in 100 individuals in the US suffer from CD, making it the most commonly diagnosed gastrointestinal disorder (Ciclitira et. al., 2005). These proline-rich gluten peptides are resistant to proteolysis and accumulate in the duodenum of the small intestine. Once in the duodenum, these peptides illicit an autoimmune response resulting in villous atrophy. Current treatment for CD requires a rigorous adherence to a gluten-free diet. Nevertheless, gluten-containing grains are …


Dna And Protein Sequence Analysis Of Neuronal Markers Neuronal Nuclei (Neun) And Doublecortin (Dcx) In The Northern Pacific Rattlesnake (Crotalus Oreganus) And Western Fence Lizard (Sceloporus Occidentalis)., Brett M. Vassar Jun 2019

Dna And Protein Sequence Analysis Of Neuronal Markers Neuronal Nuclei (Neun) And Doublecortin (Dcx) In The Northern Pacific Rattlesnake (Crotalus Oreganus) And Western Fence Lizard (Sceloporus Occidentalis)., Brett M. Vassar

Master's Theses

Neuronal Nuclei (NeuN) and Doublecortin (DCX) are neuron specific proteins that are used in histological studies of brain structure in a variety of vertebrate taxa.Antibodies against NeuN (anti-NeuN) bind to the Fox-3 protein, an RNA binding protein common in mature neurons. Anti-DCX labels a microtubule-associated protein expressed in actively dividing neural progenitor cells and migrating neurons. The DCX gene encodes a protein that is well conserved across mammalian, avian, and a few reptilian species, therefore anti-DCX staining has been used successfully across a range of vertebrate taxa. Successful neuronal staining using anti-NeuN has been demonstrated in mammals, birds, and the …


The Development Of Diving Capabilities In Weddell Seal (Leptonychotes Weddellii) Pups Throughout Early Ontogeny, Emma Weitzner Jun 2019

The Development Of Diving Capabilities In Weddell Seal (Leptonychotes Weddellii) Pups Throughout Early Ontogeny, Emma Weitzner

Master's Theses

Weddell seals (Leptonychotes weddellii) are among the deepest diving pinnipeds (i.e., seals, sea lions, and walrus) and one of the best studied marine mammals in the world; as such, these seals are considered a model species for the study of diving physiology and behavior. Adult Weddell seal dive physiology is rather comprehensively understood, yet previous research has excluded an examination of pups’ initial independent diving attempts, beginning instead with the diving capabilities of near-weaning individuals at four to five weeks of age. This is beyond the point many pups have attempted their first independent dives; pups begin to …


Development Of A Pediatric Model Of Nafld In Neonatal Iberian Pigs, Gabriella Veronica Hernandez, Victoria Alice Smith, Morgan Coffin, Daniel Columbus, Matthew Burd, Kimberly Sprayberry, Mark Edwards, Daniel Peterson, Darin Bennett, Robert Fanter, Christopher Kitts, Michael La Frano, Margaret Rice, Douglas Burrin, Magdalena Maj, Rodrigo Manjarin Jun 2019

Development Of A Pediatric Model Of Nafld In Neonatal Iberian Pigs, Gabriella Veronica Hernandez, Victoria Alice Smith, Morgan Coffin, Daniel Columbus, Matthew Burd, Kimberly Sprayberry, Mark Edwards, Daniel Peterson, Darin Bennett, Robert Fanter, Christopher Kitts, Michael La Frano, Margaret Rice, Douglas Burrin, Magdalena Maj, Rodrigo Manjarin

Master's Theses

The prevalence of non-alcoholic fatty liver disease (NAFLD) in children has increased over the past decades, creating a need for animal models that recapitulate the features of the pediatric disease. Iberian pigs have a leptin-resistant phenotype characterized by hyperleptinemia, hyperphagia, and extreme adipogenesis. We hypothesized that neonatal Iberian pigs fed a high fat high-fructose (HFF) diet will develop a pattern of liver injury resembling pediatric NAFLD. In addition, we sought to determine if a mixture of probiotics would prevent the disease. Animals were fed 1 of 4 diets containing (g/kg body weight × d) 0 g fructose, 11 g fat …


Comparative Thermal Ecology Of Coastal And Inland Pacific Rattlesnakes (Crotalus Oreganus), Hayley Layne Crowell May 2019

Comparative Thermal Ecology Of Coastal And Inland Pacific Rattlesnakes (Crotalus Oreganus), Hayley Layne Crowell

Master's Theses

Global biodiversity is declining as a direct result of anthropogenic climate change. Ectothermic species have become focal organisms for studying the ecological effects of altered climates due to the clear relationship between environmental temperatures and ectotherms’ basic physiological functions. Historically, examinations of these effects have focused heavily on heliothermic lizards, and most others have tended to focus on single populations or sympatric species within a single community. Addressing the longterm energetic implications of environmental temperature variation will provide valuable insight into the cascading physiological effects that certain populations or species may experience as a result of altered climates.

In this …


Cold Acclimation Response Of Non-Native Italian Wall Lizard (Podarcis Siculus) Populations From New York And California, Daniel Haro Dec 2018

Cold Acclimation Response Of Non-Native Italian Wall Lizard (Podarcis Siculus) Populations From New York And California, Daniel Haro

Master's Theses

Understanding how organisms respond to climatic variability and novel conditions is becoming an increasingly important task for ecologists. For ectotherms in the northern hemisphere, the response to cold is of special interest, considering that poleward range expansion events and increasing variability of temperatures during winter are already being observed as consequences of a warming planet. Though direction of change in physiological variables in response to cold is well studied in ectotherms, the extent to which traits can change and the rate at which they can change is not.

We compared the extent and rate of change in cold tolerance (CT …


Indirect Food Web Interactions: Sea Otter Predation Linked To Invasion Success In A Marine Fouling Community, Maggie F. Jenkins Dec 2018

Indirect Food Web Interactions: Sea Otter Predation Linked To Invasion Success In A Marine Fouling Community, Maggie F. Jenkins

Master's Theses

Humans have caused grave ecological and economic damage worldwide through the introduction of invasive species. Understanding the factors that influence community susceptibility to invasion are important for controlling further spread of invasive species. Predators have been found to provide biotic resistance to invasion in both terrestrial and marine systems. However, predators can also have the opposite effect, and facilitate invasion. Therefore, recovery or expansion of native predators could facilitate the spread of invasive species. Needles et al. (2015) demonstrated that the threatened southern sea otter (Enhydra lutris nereis) facilitated the invasion of an exotic bryozoan, Watersipora subatra. …


The Thermal Ecology Of Sceloporus Occidentalis, Luis Patricio Burgos Dec 2018

The Thermal Ecology Of Sceloporus Occidentalis, Luis Patricio Burgos

Master's Theses

With temperatures rising globally, assessing the possible impacts of the changing climate becomes more and more urgent. Ectotherms are excellent indicators of potential climatic ramifications on biodiversity because of their heavy reliance on the environment for their thermoregulation. Studies have historically looked at thermal tolerance values to establish predictive models for population and species extinctions.

In chapter 1, we looked at recent studies that suggest that thermal tolerance may be a plastic trait and test the effects empirically. Most studies are based on captive lizards acclimated to laboratory conditions that do not necessarily reflect natural environments, and if thermal tolerance …


The Roles Of Tid1, Ndj1, And Spo16 In Distributive Segregation During Saccharomyces Cerevisiae Meiosis, Ethan Atticus Shaw Aug 2018

The Roles Of Tid1, Ndj1, And Spo16 In Distributive Segregation During Saccharomyces Cerevisiae Meiosis, Ethan Atticus Shaw

Master's Theses

Meiosis is a specialized form of cell division in sexually reproducing eukaryotes. Crossovers are physical connections formed between homologous chromosomes during meiosis; these connections help ensure normal segregation of homologous chromosomes at meiosis I. However, the yeast Saccharomyces cerevisiae and other eukaryotes can still segregate homologs properly even in the absence of some crossovers. This is due to a backup mechanism known as distributive segregation, which correctly segregates non-crossover chromosomes at a higher rate than if segregation were completely random. To study distributive segregation, we have generated diploid yeast with one homeologous chromosome pair consisting of a Saccharomyces cerevisiae chromosome …


Zinc Sunscreens Affect Development Of Strongylocentrotus Purpuratus Embryos, Brittany E. Cunningham, Nikki L. Adams Jun 2018

Zinc Sunscreens Affect Development Of Strongylocentrotus Purpuratus Embryos, Brittany E. Cunningham, Nikki L. Adams

Master's Theses

The growing popularity of physical sunscreens will also lead to an increased release of the ingredients from zinc oxide (ZnO) sunscreens into marine environments. Though zinc (Zn) is a necessary micronutrient in the ocean, greater than natural Zn concentrations are being released into marine environments by use of sunscreens. The extent of the consequences of the addition of Zn to the ocean are not fully understood. We investigated effects of materials released by zinc oxide (ZnO) sunscreens on the development of California purple sea urchin, Strongylocentrotus purpuratus. Embryos developed in various concentrations of Zn, the sources of which included …