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Full-Text Articles in Biology
Scorpion Phylogeography In The North American Aridlands, Matthew Ryan Graham
Scorpion Phylogeography In The North American Aridlands, Matthew Ryan Graham
UNLV Theses, Dissertations, Professional Papers, and Capstones
Understanding the geographic, geologic, and climatic forces responsible for generating current patterns of biodiversity has been a central objective of phylogeography. To develop a better understanding of these processes in the North American arid lands, I used DNA sequence data and species distribution modeling to conduct three phylogeographic assessments incorporating four species of arid-adapted scorpions:Hadrurus arizonensis, H. jedediah, H. spadix,and Paruroctonus becki. In an assessment of H. arizonensis, phylogeographic patterns indicate that Pleistocene climate cycles and associated glacial refugia played a central role in structuring the genetic diversity of this species in the Mojave and Sonoran deserts, mostly supporting predictions …
Stoneflies Of Unusual Size: Population Genetics And Systematics Within Pteronarcyidae (Plecoptera), John S. Sproul
Stoneflies Of Unusual Size: Population Genetics And Systematics Within Pteronarcyidae (Plecoptera), John S. Sproul
Theses and Dissertations
Chapter 1. The family Pteronarcyidae (Plecoptera) is a highly studied group of stoneflies and very important to a wide variety of aquatic studies. Several phylogenies have been proposed for this group recent decades, however there is little congruence between the various topologies. The present study revises the phylogeny of the group by combining molecular data from mitochondrial cytochrome oxidase subunit II, ribosomal subunit 12S, ribosomal subunit 16S, and nuclear loci ribosomal subinit 18S and Histone H3, with published morphological data in a parsimony-based total evidence analysis. The analysis produced a well-supported phylogeny with novel relationships within the genus Pteronarcys. …
Diversification And Conservation In The South American Dry Biomes: Distribution Modeling And Multilocus Lizard Phylogeography, Fernanda Werneck
Diversification And Conservation In The South American Dry Biomes: Distribution Modeling And Multilocus Lizard Phylogeography, Fernanda Werneck
Theses and Dissertations
The understanding of diversification of intraspecific lineages can shed light on speciation processes and ultimately biogeographic patterns across multiple spatial and temporal scales. In this dissertation I investigated the geographical and ecological factors promoting diversification across the South American dry diagonal biomes (i.e. Cerrado, Chaco, and Seasonally Dry Tropical Forests - SDTFs), through a coupled approach between multilocus phylogeographic and geospatial methods, in the larger context of interpreting the consequences of the resulting patterns for the conservation of biodiversity and evolutionary processes. In Chapter 1 I evaluate biogeographic hypotheses previously proposed and emphasize that the dry diagonal biomes are particularly …
Evolution And Biogeography Of Fire-Eye Antbirds (Genus Pyriglena): Insights From Molecules And Songs, Marcos Maldonado Coelho
Evolution And Biogeography Of Fire-Eye Antbirds (Genus Pyriglena): Insights From Molecules And Songs, Marcos Maldonado Coelho
Dissertations
The importance of climatic and geologic factors as drivers of population differentiation and speciation in the Neotropical region has long been appreciated. However, many questions remain regarding their roles underlying the processes and patterns of diversification. Studies conducted in distinct regions containing a suite of geological and ecological conditions constitute ideal scenarios to assess the role of Pleistocene climatic changes, rivers, and mountain building as historical diversification mechanisms. In chapters 1 and 2, I used an integrative approach combining molecular phylogenetics, phylogeography and population genetics to elucidate the importance of climatic and geological factors as engines of diversification. I focused …
Molecular Phylogenetics And Phylogeography Of The American Box Turtles (Terrapene Spp.), Bradley T. Martin
Molecular Phylogenetics And Phylogeography Of The American Box Turtles (Terrapene Spp.), Bradley T. Martin
Biology Theses
The classification of the American box turtles (Terrapene spp.) has remained enigmatic to systematists. Previous comprehensive phylogenetic studies have focused primarily on morphology. The goal of this study was to re-assess the classification of Terrapene spp. by obtaining DNA sequence data from a broad geographic range and from all four species and 11 subspecies within the genus. Tissue samples were obtained for all taxa except for T. nelsoni klauberi. DNA was extracted, and the mitochondrial DNA (mtDNA) cytochrome b (Cytb) and nuclear DNA (nucDNA) glyceraldehyde-3-phosphate-dehydrogenase (GAPD) genes were amplified via polymerase chain reaction and sequenced. The sequence data were analyzed …
The Phylogeography Of The Mountain Sucker [Catostomus (Pantosteus) Platyrhynchus], Nina Johanna Laitnen
The Phylogeography Of The Mountain Sucker [Catostomus (Pantosteus) Platyrhynchus], Nina Johanna Laitnen
Theses and Dissertations
Pantosteus, a subgenus of Catostomus, includes the mountain sucker (Catostomus playthyrnchus), whose speculated older origins in the Miocene/Pliocene can provide insight into the ancient geographical events of western North America. We believe that major geologic events influencing the diversification of mountain suckers include the rise of the Colorado Plateau, the connections between the ancient Snake River system and the Lahontan system and subsequently the connection of the Snake River system to the Columbia Basin, dispersal of mountain suckers across the continental divide, as well as the Pleistocene Bonneville flood. If this is true, we should see …
Conservation And Population Biology: Genetics, Demography And Habitat Requirements Of The Atlantic Coast Beach Mice, Haakon Myklevoll Kalkvik
Conservation And Population Biology: Genetics, Demography And Habitat Requirements Of The Atlantic Coast Beach Mice, Haakon Myklevoll Kalkvik
Electronic Theses and Dissertations
The conservation biology field seeks to preserve biodiversity and the processes shaping that variation. Conservation biology is intimately tied to evolutionary research, in order to identify evolutionary distinct lineages that may be in danger of disappearing. Interestingly, patterns and processes of lineage divergence and persistence change with respect to spatial and temporal scale. I seek to evaluate biodiversity, the factors that have shaped this heterogeneity, and how this variability persists. To accomplish this I used a phylogeographic approach as well as niche and population modeling on the Peromyscus maniculatus species group found widely distributed in North America. My emphasis was …
The Effects Of Pleistocene Climatic Change On The Phylogeography Of Euploea Mulciber (Lepidoptera; Nymphalidae; Danainae), Elva Yang
Dissertations and Theses
No abstract provided.
Comparative Analysis Of Microsatellite And Mitochondrial Genetic Variation In Ixodes Scapularis, Cynthia Tak Wan Chan
Comparative Analysis Of Microsatellite And Mitochondrial Genetic Variation In Ixodes Scapularis, Cynthia Tak Wan Chan
Electronic Theses and Dissertations
Ixodes scapularis, the black legged tick, is a species endemic to North America with a range including most of the eastern-half of the United States and portions of Canada and Mexico. The tick is an important vector of diseases transmitted to humans and animals. Since its first description in 1821, the taxonomy of the species has been controversial. Biological differences have been identified in the northern and southern populations, yet no consensus exists on population structure and the causes of this disparity. Earlier molecular studies utilizing nuclear and mitochondrial genetic markers have revealed the occurrence of two distinct lineages: …