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Full-Text Articles in Life Sciences
Comparative Phylogeography Across Multiple Scales: Small Mammals, Their Ecology, Pathogens, And Drivers Of Diversification, Schuyler W. Liphardt
Comparative Phylogeography Across Multiple Scales: Small Mammals, Their Ecology, Pathogens, And Drivers Of Diversification, Schuyler W. Liphardt
Biology ETDs
Comparative phylogeography has historically been defined as the study of how genetic variation of co-distributed species has been shaped by biogeographical history. This is a mature field of study out of which several techniques have been developed directed at identifying the role ecology and geography in diversification patterns across time. I employ the tools developed in classical comparative phylogeography across multiple taxonomic scales and across regions that historically have been understudied. My first two chapters study the complex history of host-switching, codiversification, and reassortment of hantaviruses in their mammal hosts across North America. By taking a host-centric comparative phylogeographic approach …
Global Population Divergence Of A Cosmopolian Desert Plant, Victor Ryan Alfaro
Global Population Divergence Of A Cosmopolian Desert Plant, Victor Ryan Alfaro
Biology ETDs
Genetic and phenotypic variation can have different patterns within a species if it has populations with contrasting histories. Populations can have discrete differences that are shaped by different evolutionary scenarios, but within each population, range, or region, traits and association with fitness can also be affected by both edaphic and landscape variation. For my dissertation, I surveyed and experimentally analyzed variation and adaptive potential in Sahara mustard (Brassica tournefortii), a desert annual that has endemic, invasive, and agricultural populations in Africa, Asia, and the Americas. Although my multi-trait analysis generated complex results, my findings can be applied to …
The Phylogeography And Molecular Systematics Of Woodrats (Genus: Neotoma) In The American Southwest, Katrina Derieg
The Phylogeography And Molecular Systematics Of Woodrats (Genus: Neotoma) In The American Southwest, Katrina Derieg
Biology ETDs
The American Southwest is a region where many biomes converge, harboring a wide variety of habitats ranging from desert to alpine environments. Habitat heterogeneity and the confluence of multiple species ranges make the American Southwest a biodiversity hotspot. Climate cycling throughout the Quaternary has driven the dynamics of changes in species’ ranges that are recorded by genetic signatures. For example, range expansion may lead to secondary contact between previously isolated populations or species. Contact can result in multiple evolutionary outcomes, including hybridization or the reinforcement and maintenance of independent lineages. I used multi-locus species tree methods to re-examine the nominal …
"Climatic Controls Of Plant Productivity, Phenology, And Physiology In Drylands, Alesia Hallmark, Scott L. Collins, Marcy E. Litvak, Christopher D. Lippitt, Andrew D. Richardson
"Climatic Controls Of Plant Productivity, Phenology, And Physiology In Drylands, Alesia Hallmark, Scott L. Collins, Marcy E. Litvak, Christopher D. Lippitt, Andrew D. Richardson
Biology ETDs
Drylands play a critical role in global carbon dynamics. Anthropogenic climate change is causing these hot and dry regions to become increasingly hotter, drier, and more variable. This is especially concerning as drylands are some of the most sensitive regions to changes in aridity. It is critical to understand how dryland plant species might react to a changing climate. In this dissertation, I explored the relative effects of plant community composition and dominant species abundance on determining ecosystem-wide carbon dynamics. I compared the population stability of 98 dryland plant species and related stability to phenological traits. Lastly, I related branch …