DISSERTATION RESEARCH: Genetic Diversity in Different Forms of Rarity: Computer Models and Empirical Data from Lomatium (Apiaceae)

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0073137 Soltis and GitzendannerRecent estimates indicate that over 33,000 plant species (approx. 1/8 of the Earth's flora) are rare, and this number will certainly increase as human activities continue to erode habitat. In the U.S., one quarter of all plant species are considered rare. Most conservation efforts treat rare species similarly, assuming similar genetic and ecological characteristics. This view of rarity masks biological differences among rare species, prevents the emergence of general principles about rarity, and may hinder conservation efforts. Some researchers have instead recognized different forms of rarity, based on geographic range, population size in each location, and specific habitat requirements. For example, a species that occurs on a rare soil type scattered infrequently from Washington to California may be considered "rare", despite the fact that its range spans more than 1000 miles; in contrast, a species that occurs at five sites along a ridge top in central Oregon, with thousands of individuals at each site, is also considered "rare." This research is a study of the genetic differences among different forms of rare species, using both computer simulations and data from the plant genus Lomatium (desert parsley), of the parsley and carrot family. Leaf samples of different types of rare species and of related widespread species will be collected from natural habitats. These samples will be analyzed using a variety of genetic markers and statistical analyses.The research addresses the immediate conservation needs of several State- and Federally-listed rare plant species and will provide genetic data for use in managing these species. More importantly, the work will improve biologists' understanding of rare species, formulate generalizations about the genetic features of different types of rare species, make conservation biology more predictive, and contribute to improved conservation and management plans for other rare species.