The roles of history, geography, and environment in shaping landscape genetic variation and its applied significance

The decline and loss of species and genetic diversity as a result of anthropogenic change is occurring at an unprecedented rate, reshaping biodiversity and restructuring ecosystems. Population genetic variation is shaped by evolutionary processes and in turn determines the evolutionary potential of...

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Bibliographic Details
Main Author: Galland, Lanie
Other Authors: Parchman, Thomas, Peacock, Mary, Forister, Matthew, Feldman, Chris, Matocq, Marjorie
Format: Doctoral or Postdoctoral Thesis
Language:unknown
Published: 2022
Subjects:
Online Access:http://hdl.handle.net/11714/8233
Description
Summary:The decline and loss of species and genetic diversity as a result of anthropogenic change is occurring at an unprecedented rate, reshaping biodiversity and restructuring ecosystems. Population genetic variation is shaped by evolutionary processes and in turn determines the evolutionary potential of natural populations. Facilitated by recent improvements in DNA sequencing technologies, population genomic analyses can resolve patterns of genetic differentiation and evolutionary history, characterize the effects of evolutionary process on genome variation, and facilitate an understanding of how response to environmental variation may underlie local adaptation. Such analyses can inform conservation and restoration by establishing baseline patterns of genetic variation across the landscape, recognizing evolutionary significant units, sourcing propagules for restoration, and predicting species response to changing environmental conditions. Here, I applied high throughput DNA sequencing approaches to characterize the historical, spatial, and environmental factors shaping genetic variation in several systems of conservation and restoration significance. First, I investigated hierarchical genetic structure and evolutionary history of Hucho taimen (taimen, the world’s largest salmonid), listed as vulnerable by the International Union for Conservation of Nature (IUCN), across multiple river basins in Russia and Mongolia. Second, I characterized patterns of emergent population genetic structure of nonnative Oncorhynchus mykiss (rainbow trout) in the Lake Tahoe basin to inform reintroduction of the U.S. Endangered Species Act listed native cutthroat trout Oncorhynchus clarkii henshawi (Lahontan cutthroat trout). Rainbow trout have been widely introduced across the globe, stocked for >50 years into Lake Tahoe, and an understanding of population genetic structure may help inform strategies for successful native species reintroduction. Finally, I quantified spatial genetic structure, identified environmental variables ...