Digital Commons Network^™

Thermotrophy Exploratory Study, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

The question of whether environmental heat energy could be utilized as a source of energy for biological metabolism is the center of this exploratory research. In 1979, this author postulated a hypothesis for the existence of thermotrophs that could isothermally utilize environmental heat energy as a source of their energy on Earth. According to this hypothesis, the thermotrophs could be the first primitive forms of life in the early Earth environment. The chemotrophs and phototrophs that we currently are all well familiar with might have been evolved somehow from the primitive thermotrophs. Furthermore, all the organisms currently regarded as the …

An Analysis Of Water Quality At Orange County, California Beaches, Naomi Meurice

Pomona Senior Theses

Beaches in Southern California are highly recreated by residents and visitors, making beaches socially and economically important. Public health departments in coastal communities are in charge of measuring water quality and ensuring it is safe for users. Research in the past has indicated that beach water quality gets worse after storms, with bacteria levels jumping on the day of a storm and staying high for up to five days. Studies have shown these spikes in bacteria to be associated with storm runoff, with beaches closer to runoff discharge locations experiencing more impact. However, prior research has not considered the period …

Traditional Ecological Philosophy, Michael J. Desrosier

Graduate Student Theses, Dissertations, & Professional Papers

A collection of creative essays that span a range of topics centered on Indigenous environmental wisdom.

Quantifying Antarctic Krill Connectivity Across The West Antarctic Peninsula And Its Role In Large-Scale Pygoscelis Penguin Population Dynamics, Katherine L. Gallagher, Michael S. Dinniman, Heather J. Lynch

CCPO Publications

Antarctic krill (Euphausia superba) are considered a keystone species for higher trophic level predators along the West Antarctic Peninsula (WAP) during the austral summer. The connectivity of krill may play a critical role in predator biogeography, especially for central-place foragers such as the Pygoscelis spp. penguins that breed along the WAP during the austral summer. Antarctic krill are also heavily fished commercially; therefore, understanding population connectivity of krill is critical to effective management. Here, we used a physical ocean model to examine adult krill connectivity in this region using simulated krill with realistic diel vertical migration behaviors across …

Utilizing Markov Chains To Estimate Allele Progression Through Generations, Ronit Gandhi

Honors Program: Senior Projects (Public)

All populations display patterns in allele frequencies over time. Some alleles cease to exist, while some grow to become the norm. These frequencies can shift or stay constant based on the conditions the population lives in. If in Hardy-Weinberg equilibrium, the allele frequencies stay constant. Most populations, however, have bias from environmental factors, sexual preferences, other organisms, etc. We propose a stochastic Markov chain model to study allele progression across generations. In such a model, the allele frequencies in the next generation depend only on the frequencies in the current one.

We use this model to track a recessive allele …

Variation In Behavioral Strategies For Coping With Environmental Uncertainty, Allison Mclaughlin

Theses and Dissertations--Biology

My dissertation investigates how animals behaviorally respond to environmental change, especially when there is limited information about that change. Uncertainty about the environment comes in various forms, including food resources which vary unpredictably and novel cues which present an unknown level of potential risk or benefit. Various behavioral strategies help animals cope with such uncertainty. Tactics to manage unpredictable variation in food include gathering information to reduce uncertainty (sampling) and strategically adjusting preference or aversion to variation in resources (variance-sensitivity). To manage the uncertainty of a novel cue, animals may generalize their previous experience with similar cues, or they may …

The Long-Term Effects Of Wildfire Severity On Oak-Pine Communities And Their Microclimates, Scott Glenn Culbert

Theses and Dissertations--Forestry and Natural Resources

In the eastern U.S., fire-dependent tree species have historically dominated upland forest communities, but are now experiencing widespread regeneration challenges as a result of 20^th century fire suppression policies, and are being replaced by mesophytic species. Wildfires that contain areas of high burn severity may provide an important means of mitigating these challenges and facilitating fire-dependent species regeneration and recruitment into larger size classes. One mechanism by which high-severity fire can accomplish this is by modifying understory microclimate characteristics to be more conducive to these species’ growth. A wildfire within the Daniel Boone National Forest, Kentucky, USA, provided the …

Chemical Immobilization Of Helicopter-Captured Elk (Cervus Canadensis) And Survival Of Elk Calves In Southeastern Kentucky, Kathleen E. Williams

Theses and Dissertations--Forestry and Natural Resources

Safe and effective chemical immobilization is critical to minimize stress and risk of injury when capturing free-ranging, wild ungulates. Many traditionally favored high potency opioids have been phased out or become unavailable because of increased regulations, leading to the development of two pre-mixed combination drugs, butorphanol-azaperone-medetomidine (BAM) and nalbuphine-medetomidine-azaperone (NalMed-A). Both drugs have been used to chemically immobilize ungulates, but their efficacy has not been documented in elk captured and transported via helicopter. During 2020 – 2022, we chemically immobilized helicopter-captured female elk (Cervus canadensis) with a single IM-injection of BAM (n = 41) or NalMed-A (n = …

Between Choice And Compulsion: An Examination And Critique Of The Evolution Of 'Original Sin', Matthew James Wynn

Graduate Theses/Dissertations

“Why are we the way that we are?” is one of the hardest questions to answer because it requires grasping the origin of human beings. This has left philosophers and theologians in century-long debates on forming a “cosmogony of ontology” (i.e., how the origin of the universe informs the human condition). The concept, “original sin” was developed by a North African theologian named Augustine (354 – 430 CE). Augustine’s reading of Genesis 3, and inaccurate translation of Romans 5:12, taught that a person is born morally culpable for a fault antecedent to their existence. This way of thinking about the …

Activity Patterns Of The Critically Endangered Central American River Turtle (Dermatemys Mawii), Cora Dyslin

Graduate Theses/Dissertations

The Central American River Turtle (Dermatemys mawii) is native to southern Mexico, eastern Guatemala, and Belize and is primarily restricted to watersheds that drain into the Gulf of Mexico and Caribbean Sea. Hunting, both for personal consumption and market meat, has been the primary driver of declines, and the species is now classified as critically endangered. Results from past studies that have used netting and visual surveys to detect D. mawii suggest that the species is chiefly nocturnal. However, it is unclear to what extent the perception of nocturnality has been biased by the timing of survey efforts …

The Anatomy And Phylogeny Of A New Large Plioplatecarpine Mosasaur From The Campanian Bearpaw Shale Of Montana (Usa), Richard A. Carr

Master's Theses or Doctor of Nursing Practice

In 2018, a large and associated plioplatecarpine mosasaur skull, pectoral girdle, and rib cage, whose total body length may have exceeded five meters, was uncovered in the Late Campanian Bearpaw Shale of Northeast Montana (USA). Phylogenetic analysis of this specimen, MOR 10855, recovers this individual as a basal member of the genus Plioplatecarpus. This specimen, is unique in that it is estimated to be nearly twice the size of any of the other species of Plioplatecarpus found in the Western Interior Seaway during this part of the Cretaceous. While the included phylogenetic study suggests MOR 10855 represents a new …

Advancing Assessments Of Climate Change Vulnerability Of West Virginia Watersheds, Joseph T. Molina

Graduate Theses, Dissertations, and Problem Reports (ETD)

As climate change is becoming increasingly recognized as a threat to aquatic ecosystems, climate adaptation planning, in both the long- and short-term, is becoming more common in natural resource management. There is a need within conservation agencies to develop methodologies and assessments that support adaptation planning to efficiently disperse conservation dollars and effectively strengthen ecological and community resilience as climate changes continue. My thesis aims to provide West Virginia natural resources managers with climate vulnerability assessments that can be used to determine where and how conservation efforts should be administered. Additionally, I demonstrate a methodology that can be built upon …

White-Tailed Deer In A Winter-Wonderland: Long-Term Deer Yard Use And Methodological Considerations For Ungulate Fecal Dna Metabarcoding, Melanie A. Ottino

Dissertations, Master's Theses and Master's Reports

Northern white-tailed deer (Odocoileus virginianus) mitigate the increased energetic costs of severe winter conditions through obligate migration to densely congregated areas with abundant conifer cover, a behavior referred to as yarding. “Deer yards” in the Western Upper Peninsula (UP) of Michigan are principally located within the reduced snowpack and increased ambient temperature microclimates of densely canopied eastern hemlock (Tsuga canadensis) stands, but specific drivers of long-term site fidelity and utilization are largely uncharacterized. As an important game species of high economic and cultural value and a keystone herbivore with critical impact of plant community composition and structure, identifying winter yarding …

Tropical Plant Physiological Responses To Experimental Warming And Hurricane Disturbance, Robert Tunison

Dissertations, Master's Theses and Master's Reports

Tropical forests exchange more carbon with the atmosphere than any other biome, but their responses to climate change are largely understudied. The work presented in this dissertation uses a tropical understory warming experiment that was hit by a hurricane disturbance to investigate how plant physiology responds to multiple types of climate change pressures. We measured the potential for root respiration, leaf photosynthesis & respiration, and leaf thermotolerance acclimation to experimental warming while recovering from hurricane disturbance. We found there was thermal acclimation via decreased ecosystem root respiration, increased photosynthetic thermal niche breadth, and decreased quantum efficiency for some species at …

Characterization Of Vernal Pools Across National Parks In The Great Lakes Region, Samantha R. Kurkowski

Dissertations, Master's Theses and Master's Reports

Vernal pools are small, ephemeral wetlands that become inundated each spring and provide many ecosystem services to the surrounding upland forests. They also provide critical habitat for amphibians and invertebrates, as their temporary nature keeps them free of fish and reduces predator populations. As part of a mapping project, we collected baseline field data on vernal pool characteristics throughout five Great Lakes National Parks: Pictured Rocks National Lakeshore, Sleeping Bear Dunes National Lakeshore, Apostle Islands National Lakeshore, Isle Royale National Park, and Voyagers National Parks. Our goals were to characterize and assess how vernal pools vary within and across the …

Identifying Spatial Heterogeneity In And Potential Biological Consequences Of River Thermal Environments, Keith Jeffrey Fritschie

Dartmouth College Ph.D Dissertations

Temperature is a nearly ubiquitous driver of ecological and evolutionary processes, especially for organisms whose body temperature changes with the environment. The overarching biological importance of environmental temperature and increased availability of temperature datasets have led to its inclusion in spatially continuous models of species’ performance, abundance, and distribution. However, variation in both environmental temperature and animal behavior at finer scales than captured by these models may reduce the accuracy of their scientific conclusions and conservation recommendations. Here I contribute to an improved understanding of thermal variability in river systems and its potential biological consequences for an iconic coldwater species, …

Biogeography Of Special Metabolites Produced By Ant-Associated Bacteria, Katherine Hansen

Scripps Senior Theses

There is an urgent and growing need for novel antibiotics with the growing prevalence of antibiotic-resistant pathogens. Ecologically-guided discovery is a strategy that focuses on how and where specially evolved metabolites such as antibiotics are used in nature. This strategy reveals unique active molecules with potential for human use. An unexplored niche with great potential for antibiotic discovery exists with Southwestern fungus-farming Trachymyrmex ants and their Actinobacteria symbionts. In exchange for nutrients from the ant, the ants’ bacterial symbiont produces antifungal molecules that protect the ants’ fungal cultivar from invasion by pathogenic microorganisms. They also produce antibacterial molecules to protect …

Developmental Consequences Of Hatching Asynchrony In Boat-Tailed Grackles (Quiscalus Major), Emily Radner

Scripps Senior Theses

Boat-tailed grackles (Quiscalus major) typically lay clutches of three eggs and begin incubation before the clutch is complete, resulting in hatching asynchrony. To study the developmental consequences of hatching asynchrony on boat-tailed grackles, data loggers measured nest temperatures and were compared to ambient temperatures to see when incubation began, and it appeared to begin after the second egg is laid. The third laid egg had a significantly shorter lay to pip time and lay to hatch time than the first laid egg, highlighting the need to investigate the consequences of a shortened incubation time on development. To do …

Integrating Human Dimensions In Decadal-Scale Prediction For Marine Social Ecological Systems: Lighting The Grey Zone, Jess Melbourne-Thomas, Desiree Tommasi, Marion Gehlen, Eugene J. Murphy, Jennifer Beckensteiner, Francisco Bravo, Tyler D. Eddy, Mibu Fischer, Elizabeth Fulton, Mayya Gogina, Eileen Hofmann, Maya Ito, Sara Mynott, Kelly Ortega-Cisneros, Anna N. Osiecka, Mark R. Payne, Romeo Saldívar-Lucio, Kim J.N. Scherrer

CCPO Publications

The dynamics of marine systems at decadal scales are notoriously hard to predict-hence references to this timescale as the "grey zone" for ocean prediction. Nevertheless, decadal-scale prediction is a rapidly developing field with an increasing number of applications to help guide ocean stewardship and sustainable use of marine environments. Such predictions can provide industry and managers with information more suited to support planning and management over strategic timeframes, as compared to seasonal forecasts or long-term (century-scale) predictions. The most significant advances in capability for decadal-scale prediction over recent years have been for ocean physics and biogeochemistry, with some notable advances …

Seasonal Habitat Preference And Foraging Behaviour Of Post-Moult Weddell Seals In The Western Ross Sea, Kimberly T. Goetz, Michael S. Dinniman, Luis A. Hückstädt, Patrick W. Robinson, Michelle R. Shero, Jennifer M. Burns, Eileen E. Hofmann, Sharon E. Stammerjohn, Elliott L. Hazen, David G. Ainley, Daniel P. Costa

CCPO Publications

Weddell seals (Leptonychotes weddellii) are important predators in the Southern Ocean and are among the best-studied pinnipeds on Earth, yet much still needs to be learned about their year-round movements and foraging behaviour. Using biologgers, we tagged 62 post-moult Weddell seals in McMurdo Sound and vicinity between 2010 and 2012. Generalized additive mixed models were used to (i) explain and predict the probability of seal presence and foraging behaviour from eight environmental variables, and (ii) examine foraging behaviour in relation to dive metrics. Foraging probability was highest in winter and lowest in summer, and foraging occurred mostly in …

Soil And Compost Tea: A New Restoration Technique?, Carol E. Day

Master's Theses and Doctoral Dissertations

Historically, prairie restorations have lacked the plant diversity seen in remnant prairies. Most restoration practices focus on reestablishing the plant community but overlook the soil microbial community even though microbes are critical to habitat functioning. Developing techniques that increase soil microbes in prairie restorations is critical to ensuring diverse restored habitats. We compared how microbial communities differed between remnant and restored prairie sites. We also investigated if soil and compost teas could be used to reintroduce microbes to restored prairie soil and if the teas affected native plant establishment. We found significant differences in the levels of bacterial taxa between …

Teaching Agroecology: Preparing Students For Navigating Uncharted Territory, Charles A. Francis, Steve Gliessman

Department of Agronomy and Horticulture: Faculty Publications

Agroecologists understand that farming and food systems are more complex than the aggregation of their components. This realization drives our choices of learning strategies and activities that will prepare students for complexity and uncertainty. Our quest for a just, sustainable, and nutritious food system adequate to equitably serve everyone on the planet today and into the future is an enormous challenge. An undertaking of this magnitude will be met only with major adjustments informed by thoughtful teaching and practicing problem solving skills through a new educational lens. The principles of agroecology help us focus this lens on the wicked problems …

Potential Effects Of Road Proximity On Zooplankton Communities And Water Quality In Lakes In The Northwest Territories, Marie N. Hannan

Theses and Dissertations (Comprehensive)

Studies conducted along Canada’s Dempster Highway in the Northwest Territories have shown that road dust can affect water quality in roadside lakes, leading to higher calcium, conductivity, and pH levels. These water quality changes have the potential to affect important members of the lower aquatic food web, such as zooplankton.

For my thesis research, I had two main objectives: 1) To determine if changes in water chemistry caused by deposition of road dust affects zooplankton communities; and 2) To examine if the type of roadside vegetation influences the effects of road dust on aquatic habitats. To achieve these objectives, I …

Plant Sentience Revisited: Sifting Through The Thicket Of Perspectives, Paco Calvo, Miguel Segundo-Ortin

Animal Sentience

In our target article (Segundo-Ortin & Calvo 2023), we proposed the intriguing possibility of plant sentience, drawing parallels with non-human animal studies. This response aims to sift through the rich thicket of perspectives offered by our commentators. To do so, we assess the risks of employing double standards, as well as the tendencies of anthropomorphizing and zoomorphizing in plant studies. We also emphasize the need for clarity in linguistic and conceptual terms, examine the neurophysiological evidence for plant sentience, and discuss the ethical implications of such recognition.

Harnessing Citizen Science And Collections Data For Invasive Plant Surveillance, Adin L. Ring

Library Map Prize

Our main source of information about the distribution of invasive plants in the United States comes from occurrence records in three categories: biological collections (physical plant specimens in museums), citizen science (opportunistic observations by untrained civilians), and invasion monitoring (structured observation by government or non-profit agencies). This study compiles a set of 3.1 million occurrence records of 3,578 introduced plant species in the continental United States, and infers spatial, temporal, and taxonomic biases by comparing the three categories of data. We find that citizen science contributes the largest bulk of records, and does better capturing visually conspicuous plants and very …

Unraveling A Paradox Of Habitat Relationships: Scale-Dependent Drivers Of Temporal Occupancy-Abundance Relationships In A Cooperatively Breeding Bird, Natasha D.G. Hagemeyer, Mario B. Pesendorfer, Walter D. Koenig, Eric L. Walters

Biological Sciences Faculty Publications

Context Spatial occupancy and local abundance of species often positively covary, but the mechanisms driving this widespread relationship are poorly understood. Resource dynamics and habitat changes have been suggested as potential drivers, but long-term studies relating them to abundance and occupancy are rare. In this 34-year study of acorn woodpeckers (Melanerpes formicivorus), a cooperatively breeding species, we observed a paradoxical response to changes in habitat composition: despite a reduction in the availability of high-quality breeding habitat, the population increased considerably.

Objectives We investigated the role of annual variation in food availability and long-term changes in habitat composition as predictors …

Western Gulls’ (Larus Occidentalis) Reproductive And Behavioral Responses To Human Disturbance, Lilamarie 'Asta Bowen

Cal Poly Humboldt theses and projects

Human disturbances can negatively affect wildlife by causing stress, altering behavior, or even impacting populations through changes in survival or productivity. Colonial-nesting seabirds are of particular concern due to population declines and their gregarious and conspicuous nature, which may attract human visitors. However, the effects of nearby human activities, though frequently negative, could be neutral or even positive through phenomena like habituation to human activities or subsidization by human-supplied food sources. In this observational study, I evaluated relative support for three hypotheses which may explain how Western Gulls are impacted by human activity: disturbance, habituation, and subsidization. I investigated this …

Genetic Evaluation Of The Current Distribution And Possible Diffrentations Between Lasiurus Borealis And Lasiurus Frantzii In Southwestern North America, Zeinab M. Haidar

Cal Poly Humboldt theses and projects

Several recent accounts of overlap and historic misidentifications regarding two species of the genus Lasiurus, Western red bat (Lasiurus frantzii) and Eastern red bat (Lasiurus borealis), have cast doubt on our understanding of their distribution, assumed spatial allopatry, and interactions in the United States Southwest. With the use of morphometrics and genetic sequencing, utilizing tissue collected from specimens throughout California and adjoining states, we have reassessed the current distribution, best practices for field identification, and genetic differentiation between both species. Appropriate species classification by region was achieved utilizing mitochondrial DNA, targeting the cytochrome c oxidase …

Using Multiscale Ensemble Habitat Models To Identify Wildfire Risk To Habitat For An Iconic Forest Species, Logan Baker Hysen

Cal Poly Humboldt theses and projects

Large and severe wildfires, exacerbated by climate change and human behavior, are occurring more frequently in many forests across the western United States. While wildfire is a natural part of most terrestrial ecosystems, rapidly changing fire regimes have the potential to alter habitat beyond the adaptive capabilities of species. Spatial assessments of wildfire risks to species habitat may allow managers to pinpoint locations for management activities. To illustrate this, I spatially assessed wildfire risk within habitat that supports the nesting activity of the federally threatened northern spotted owl (Strix occidentalis caurina) in the California redwood coast ecoregion. To …

Intestinal Parasite Infection In Tibetan Macaques (Macac Thebetana) In Eastern China, Miarisoa Ramilison

All Master's Theses

Grooming is one of the crucial social behaviors of primate species that functions to remove parasites and maintain social bonds. Although, much data exists to support the idea that grooming is essential in forming and sustaining social bonds among individuals, there is a lack of information about the extent to which it removes ectoparasites or contributes to the spread of internal parasites. To fill this gap in the literature, we investigated the relationship between social contact behavior including grooming and intestinal parasite infection in Tibetan macaques (Macaca thibetana). This species lives at Mt. Huangshan in China. We used …