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Climate Change And The Evolution Of Insect Immune Function, Danae Perry
Climate Change And The Evolution Of Insect Immune Function, Danae Perry
Electronic Theses and Dissertations
Insects are ectothermic organisms that have physiological, behavioral and life-history traits directly influenced by their environment. Investigations have shown that many insects use melanin to permanently darken their cuticles in cooler or drier climates to improve thermoregulation and desiccation resistance. Melanin is a major component of pathogen defense in insects. This suggests that environmentally driven adaptive changes in cuticular melanin may non-adaptively shape insect immune function. This hypothesis has been referred to as climate-related Cuticle Dependent Immune Investment (climate-related CDII). Climate-related CDII also suggests that a warming climate could lead to the evolution of a weakened melanin-based immune response due …
Advanced Castes At The Outset Of Eusociality In Wasps (Vespidae), Patrick Piekarski
Advanced Castes At The Outset Of Eusociality In Wasps (Vespidae), Patrick Piekarski
Electronic Theses and Dissertations
A dominating and widespread view is that evolutionary change is gradual and waits upon mutation. Likewise, it is thought that workers and queens of eusocial insects diverged gradually and stepwise. That is, rudimentary castes preceded advanced castes. This paradigm hinges on eusociality having evolved once in Vespidae, and primitively eusocial paper wasps lacking ontogenetic caste biasing (differentiation of castes during larval development). Using a phylogenomic approach this study shows strong evidence for two origins of eusociality in vespid wasps, wherein one origin is likely characterized by the sudden appearance of castes with physiological, and perhaps even morphological, differences established before …
Plasticity Of Central And Peripheral Nervous System: Effects Of Oxygen-Glucose Deprivation (Ogd) And Chronic Intermittent Hypoxia (Cih), Jin Chen
Electronic Theses and Dissertations
Transient receptor potential canonical 6 (TRPC6) channels are permeable to Na+ and Ca2+ and are widely expressed in the brain. In this study, we investigated the role of TRPC6 following ischemia/reperfusion (I/R) and oxygen-glucose deprivation (OGD). We found that TRPC6 expression was increased in wild type (WT) mice cortical neurons following I/R and in primary neurons with OGD, and that deletion of TRPC6 reduced the I/R-induced brain infarct in mice and the OGD- /neurotoxin-induced neuronal death. Using live-cell imaging to examine intracellular Ca2+ levels ([Ca2+]i), we found that OGD induced a significant higher increase in glutamate-evoked Ca2+ influx compared to …
The Behavior Of Humans And Wildlife With Respect To Roads: Insights For Mitigation And Management, Molly Grace
The Behavior Of Humans And Wildlife With Respect To Roads: Insights For Mitigation And Management, Molly Grace
Electronic Theses and Dissertations
Road ecology is the study of how roads and wildlife interact. Traditionally, road ecologists have primarily focused on one effect of roads: roadkill. Though roadkill can have devastating effects on wildlife populations, roads have sub-lethal impacts that are gaining more and more attention from the scientific community. These sub-lethal impacts include noise, light, and chemical pollution as well as altered habitat structure, which can all influence animal behavior. In this dissertation, I applied a behavioral ecology framework to study specific lethal and sub-lethal road effects with the goal of improving mitigation efforts. In Chapters 1 and 2, I evaluated how …
A Major Dna Double Strand Repair Pathway And Cancer-Associated Circulating Proteins Are Effecters Of Epigenetic Revision., Brittany Allen
A Major Dna Double Strand Repair Pathway And Cancer-Associated Circulating Proteins Are Effecters Of Epigenetic Revision., Brittany Allen
Electronic Theses and Dissertations
DNA methylation is a vital epigenetic process that acts as a major control mechanism for gene expression. In addition to its essential role in many normal cellular processes, it is also implicated in a wide variety of disease states and processes including cancer. Along with genetic mutations, aberrant DNA methylation patterns, specifically the inappropriate DNA methylation or demethylation of CpG residues, may activate oncogenes or suppress tumor suppressor genes, respectively. These changes can generate or facilitate the progression of tumorigenesis and tend to accumulate throughout the development of cancer. Although they play such a major role in cancer and in …
A Chemical And Genetic Approach To Study The Polyamine Transport System In Drosophila, Minpei Wang
A Chemical And Genetic Approach To Study The Polyamine Transport System In Drosophila, Minpei Wang
Electronic Theses and Dissertations
Polyamines are small cationic molecules that play important roles in most vital cellular processes including cell growth and proliferation, regulation of chromatin structure, translation and programmed cell death. Cellular polyamine pools are maintained by a balance between biosynthesis and transport (export and import). Increased polyamine biosynthesis activity and an active transport system are characteristics of many cancer cell lines, and polyamine depletion has been shown to be a viable anticancer strategy. Polyamine levels can be depleted by α-difluoromethylornithine (DFMO), an inhibitor of the key polyamine biosynthesis enzyme ornithine decarboxylase. However, malignant cells often circumvent DFMO therapy by up-regulating polyamine import; …
Go With The Flow: Patterns Of Connectivity In Low Dispersal Coral Reef Gobies (Coryphopterus Spp.) Throughout The Western Atlantic, Daniel Volk
Electronic Theses and Dissertations
Gene flow is an integral biological process that can mediate speciation. While many consider the ocean to be an open environment, there are many barriers that limit gene flow, particularly in the western Atlantic. I analyzed data from two widespread, coral reef fishes, the bridled goby (Coryphopterus glaucofraenum) and sand-canyon goby (C. venezuelae), throughout their range in the western Atlantic. Using two genetic datasets, mitochondrial DNA (mtDNA) and genomic SNPs, I investigated the evolutionary history of these species and inferred the location and strength of putative barriers. My results suggest that several unique lineages have genetically diverged from one another …
The Paths Less Traveled: Movement Of Gopher Tortoises Along Roads And Railways, Rhett Rautsaw
The Paths Less Traveled: Movement Of Gopher Tortoises Along Roads And Railways, Rhett Rautsaw
Electronic Theses and Dissertations
Urbanization and an expanding human population have led to a large degree of habitat destruction and fragmentation. These, in turn, reduce biodiversity and wildlife population sizes on a global scale. Transportation infrastructure, such as roads and railways, are some of the largest contributors to habitat fragmentation. Roads are well-established to negatively impact wildlife, but some studies suggest a potential use in habitat connectivity by functioning as wildlife corridors to connect distant populations. Railways are similarly known to impact wildlife by increasing mortality rates as well as provide unique risks such as electrocution and entrapment when compared to roads. However, the …
Mucking About: Hydrologic Regime And Soil Carbon Storage In Restored Subtropical Wetlands, Alicia Huber
Mucking About: Hydrologic Regime And Soil Carbon Storage In Restored Subtropical Wetlands, Alicia Huber
Electronic Theses and Dissertations
Wetlands are extremely important ecosystems that have declined drastically worldwide, continue to be lost, and are threatened globally. They perform a number of important ecosystem services such as flood control, provide habitat for many species, and have aesthetic and recreational value. Wetlands are also important to the global carbon (C) cycle. Wetland soils are especially effective C sinks because they have high primary productivity and low decomposition rates due to flooded, anoxic conditions. Increased recognition of wetlands' value has led to more ecological and hydrological restoration of degraded wetlands to mitigate the effects of wetland destruction. Hydrological restoration, which attempts …
Using Biomarkers To Assess The Migratory Ecology And Reproduction Of The Florida Green Turtle (Chelonia Mydas), Ryan Chabot
Using Biomarkers To Assess The Migratory Ecology And Reproduction Of The Florida Green Turtle (Chelonia Mydas), Ryan Chabot
Electronic Theses and Dissertations
Migratory connectivity between breeding and foraging areas is a vital component of the ecology of a diverse collection of marine vertebrates. Habitat quality, composition, and resource availability at these locations have direct ramifications for individual fitness. The green turtle (Chelonia mydas) is a long-lived, highly migratory species of conservation concern. Important green turtle nesting habitat in Florida is protected, but more information is needed to identify foraging habitats and the influence these habitats have on reproduction. Here, I used stable isotope analysis of δ13C, δ15N, and δ34S and satellite telemetry validation to determine the number of putative foraging areas used …
Cross-Continental Insights Into Jaguar (Panthera Onca) Ecology And Conservation, Joe Figel
Cross-Continental Insights Into Jaguar (Panthera Onca) Ecology And Conservation, Joe Figel
Electronic Theses and Dissertations
The jaguar (Panthera onca) is a widely distributed large carnivore and the focal species of a range-wide connectivity initiative known as the jaguar conservation network (JCN). Comprised of ~83 Jaguar Conservation Units (JCUs) and ~75 corridors from northern Mexico to Argentina, the JCN functions as a conduit for jaguar movement and gene flow. Key linkages in the network are imperiled by human population growth, large-scale agriculture, highway expansion, and other infrastructural development. Labeled "corridors of concern," these vulnerable linkages are imperative to the maintenance of connectivity and genetic diversity throughout jaguar distribution. I take a multi-faceted approach to analyze conservation …
Reproductive Life History And Signal Evolution In A Multi-Species Assemblage Of Electric Fish, Joseph Waddell
Reproductive Life History And Signal Evolution In A Multi-Species Assemblage Of Electric Fish, Joseph Waddell
Electronic Theses and Dissertations
Animals that co-occur in sympatry with multiple closely-related species use reproductive mate attraction signals not only to assess the quality of a potential conspecific mate (sexual selection), but also to discriminate conspecifics from heterospecifics (species recognition). However, the extent to which sexual selection and species recognition may interact, or even conflict, is poorly known. Neotropical electric fish offer unrivaled opportunities for understanding this problem. They generate simple, stereotyped mate attraction signals that are easy to record and quantify, and that are well-understood from the neurobiological perspective. Additionally, they live in electrically-crowded environments, where multiple congeners live and reproduce in close …
The Role Of The Y-Chromosome In The Evolution Of Autosomally Coded Traits, Ian Kutch
The Role Of The Y-Chromosome In The Evolution Of Autosomally Coded Traits, Ian Kutch
Electronic Theses and Dissertations
Recent work indicates that the Y-chromosome of the fruit fly Drosophila melanogaster can influence gene regulation on the autosomes and X chromosome. This newly discovered function of the Y has the potential to dramatically shape the regulatory evolution of numerous genes that reside throughout the genome; even for genes that code for both male and female traits. Given that the mechanism underlying the Y-linked influence on gene expression in D. melanogaster appears to exist in other independently evolved heterogametic sex chromosomes, the evolutionary implications of Y-linked regulatory variation (YRV) deserves to be explored. These implications include the potential for Y-chromosomes …
Using Molecular Genetic And Demographic Tools To Improve Management Of Ex Situ Avian Populations, Gina Ferrie
Using Molecular Genetic And Demographic Tools To Improve Management Of Ex Situ Avian Populations, Gina Ferrie
Electronic Theses and Dissertations
Small populations, specifically those that are isolated from others, are more prone to extinction than larger inter-connected populations. The risks that these small isolated populations face include loss of genetic diversity due to founder effects and inbreeding due to population bottlenecks, as well as demographic uncertainty due to fluctuating fecundity and mortality rates and impacts of external environmental factors. Ex situ populations, including those managed as conservation breeding programs with species recovery aims, as well as those that do not have reintroduction goals but are managed for long term population sustainability, suffer from the same extinction risks as small and …
The Effect Of Parental Population Density On Offspring Immune Function, Dana Davis
The Effect Of Parental Population Density On Offspring Immune Function, Dana Davis
Electronic Theses and Dissertations
It is well known that an individual's environment, genetic code, and gene by environment interactions have an effect on its overall phenotype. However, there is a growing body of work that shows that parents can have an effect on their offspring's phenotype beyond the inherited genetic code. Studies have shown that parents may affect their offspring through physiological mechanisms such as egg provisioning and epigenetic effects and through behavioral mechanisms such as maternal care. In many of these cases, the parental effect is triggered by an environmental cue. Previous work has shown that density can impact immune function and cuticle …