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Full-Text Articles in Population Biology

Geographic Population Structure And Taxonomic Identity Of Rhinichthys Osculus, The Santa Ana Speckled Dace, As Elucidated By Nuclear Dna Intron Sequencing, Liane Raynette Greaver Sep 2019

Geographic Population Structure And Taxonomic Identity Of Rhinichthys Osculus, The Santa Ana Speckled Dace, As Elucidated By Nuclear Dna Intron Sequencing, Liane Raynette Greaver

Electronic Theses, Projects, and Dissertations

Rhinichthys osculus (Cyprinidae), the speckled dace, is the most widely distributed freshwater fish in the western United States. The southern California populations of R. osculus are identified as the Santa Ana speckled dace (SASD), though the SASD has not yet been formally recognized as a distinct taxon. Current mtDNA analysis performed in the Metcalf Lab has shown a reciprocally monophyletic relationship among three California regions; southern, central coast, and Owens Valley. Similarly, microsatellite genotyping has shown significant levels of geographic population structure. The purpose of this study was to provide nuclear DNA sequence data to determine the taxonomic status of …


Response Of Early Life Stage Homarus Americanus To Ocean Warming And Acidification: An Interpopulation Comparison, Maura K. Niemisto Aug 2019

Response Of Early Life Stage Homarus Americanus To Ocean Warming And Acidification: An Interpopulation Comparison, Maura K. Niemisto

Electronic Theses and Dissertations

Anthropogenic carbon released into the atmosphere is driving rapid, concurrent increases in temperature and acidity across the world’s oceans, most prominently in northern latitudes. The geographic range of the iconic American lobster (Homarus americanus) spans a steep thermal gradient and one of the most rapidly warming oceanic environments. Understanding the interactive effects of ocean warming and acidification on this species’ most vulnerable early life stages is important to predict its response to climate change on a stage-specific and population level. This study compares the responses of lobster larvae from two sub-populations spanning New England’s north-south temperature gradient (southern …


Mixing It Up: The Impact Of Episodic Introgression On The Evolution Of High-Latitude Mesocarnivores, Jocelyn P. Colella Jul 2019

Mixing It Up: The Impact Of Episodic Introgression On The Evolution Of High-Latitude Mesocarnivores, Jocelyn P. Colella

Biology ETDs

At high latitudes, climatic oscillations have triggered repeated episodes of organismal divergence by geographically isolating populations. For terrestrial species, extended isolation in glacial refugia – ice-free regions that enable terrestrial species persistence through glacial maxima – is hypothesized to stimulate allopatric divergence. Alternatively, upon glacial recession, divergent populations expanded from independent glacial refugia and often contacted other diverging populations. In the absence of reproductive isolating mechanisms, this biogeographic process may trigger hybridization and ultimately, gene flow between divergent taxa. My dissertation research aims to understand how these episodic periods of isolation and contact have impacted the evolution of high latitude …


Using Environmental Dna And Occupancy Modeling To Estimate Rangewide Metapopulation Dynamics Of The Endangered Tidewater Goby Eucyclogobius Spp., Chad M. Martel Jan 2019

Using Environmental Dna And Occupancy Modeling To Estimate Rangewide Metapopulation Dynamics Of The Endangered Tidewater Goby Eucyclogobius Spp., Chad M. Martel

Cal Poly Humboldt theses and projects

Conservation of species is most effective when metapopulation dynamics are well understood and incorporated into management plans, allowing managers to target conservation efforts where they will be most effective. The development of environmental DNA (eDNA) methods provides an efficient and highly sensitive approach to generate presence and absence data needed to elucidate metapopulation dynamics. Combining sample detection histories from eDNA surveys with occupancy models that account for non-detection can offer unbiased estimates of rangewide metapopulation dynamics. However, traditional occupancy models do not allow direct evaluation of the drivers of site occupancy, extinction, and colonization. Herein, I utilize a novel dynamic …


Population Health Of Spotted Salamanders (Ambystoma Maculatum) In Created Vernal Pools: An Integrative Approach, Alice R. Millikin Jan 2019

Population Health Of Spotted Salamanders (Ambystoma Maculatum) In Created Vernal Pools: An Integrative Approach, Alice R. Millikin

Graduate Theses, Dissertations, and Problem Reports

Habitat creation is an important tool for conservation to counteract habitat loss and degradation. Vernal pools are susceptible to destruction due to limited detection, protection, and regulation. These wetlands provide fishless breeding habitat for many amphibian species including spotted salamanders (Ambystoma maculatum) in eastern North America. Determining whether created vernal pool habitat is successful is often determined by demographic data of colonizing populations. I suggest that hormone levels, population genetics, and disease prevalence can improve our understanding of population health in created habitat. The goal of this dissertation was to assess the health of spotted salamander larvae in …


A Novel Snp Genotyping Technique To Determine Orangutan Relatedness And Genetic Diversity At Camp Leakey In Tanjung Puting, Central Kalimantan, Ruth Ella Linsky Jan 2019

A Novel Snp Genotyping Technique To Determine Orangutan Relatedness And Genetic Diversity At Camp Leakey In Tanjung Puting, Central Kalimantan, Ruth Ella Linsky

All Master's Theses

Genetic studies of dispersal patterns in wild populations of orangutans (Pongo spp.) have sought to confirm behavioral observations that female orangutans tend to stay near their natal range while males disperse. In order to genotype a previously unsampled wild population of endangered orangutans at Tanjung Puting National Park I developed novel application of a methyl based magnetic capture for enrichment of fecal DNA and commercial human targeted single nucleotide polymorphism (SNP) microarray technology. I confirmed results of this new genotyping technique through standard microsatellite short tandem repeat (STR) micro-capillary genotyping. I estimate genetic diversity and relatedness (r) …


Spatial Genetic Structure And Local Adaptation Within And Among Foxtail Pine (Pinus Balfouriana Subsp. Balfouriana) Populations Located In The Klamath Mountains, California, Rebecca D. Piri Jan 2019

Spatial Genetic Structure And Local Adaptation Within And Among Foxtail Pine (Pinus Balfouriana Subsp. Balfouriana) Populations Located In The Klamath Mountains, California, Rebecca D. Piri

Theses and Dissertations

Foxtail pine (Pinus balfouriana) is a subalpine conifer endemic to California, notably separated into two disjunct subspecies. Previous studies have described the northern subspecies,Pinus balfouriana subsp. balfouriana,as having an uncommonly high level of genetic differentiation and no discernible spatial patterns in phenotypic variation. This study seeks to characterize the spatial genetic structure and patterns of selection of the northern subspecies (Pinus balfouriana subsp. balfouriana) using genome-wide data and to identify the influence of ecology and environment on the unique genetic patterns. I show that genetic differentiation among populations is much less than previously estimated …


Impact Of Seasonal And Host-Related Factors On The Intestinal Microbiome And Cestode Community Of Sorex Cinereus And Sorex Monticola, Katelyn D. Cranmer Jan 2019

Impact Of Seasonal And Host-Related Factors On The Intestinal Microbiome And Cestode Community Of Sorex Cinereus And Sorex Monticola, Katelyn D. Cranmer

Electronic Theses and Dissertations

The intestinal microbiome of mammals plays a significant role in host health and response to environmental stimuli and can include both beneficial native bacteria as well as parasitic worms. In this study, I examined the intestinal cestode and bacterial communities of two closely related species of shrew, Sorex monticola and Sorex cinereus, over a six month period in 2016. Specimens were collected approximately every three weeks from May to October from the Sangre de Cristo Mountains in Cowles, New Mexico. A total of 79 shrews were prepared with the gastrointestinal tracts removed and flash-frozen in liquid nitrogen. An additional …