The purpose of this research is to provide eneral guidelines for assessing risks of extinction in rare plants on oceanic islands by studying their genetic and morphological variation and aspects of the reproductive biology/. Allozymes and RAPDs will be used to measured diversity within populations of different sizes in selected species of rare plants on the Juan Fernandez Islands that differ in reproductive biology. This will determine whether smaller populations may be at greater risk of extinction because of lower genetic diversity and/or reduced seed set due to inbreeding depression, lack of pollinators, or skewed sex ratios in dioecious species. The level and apportionment of genetic diversity within and among populations of species differing in aspects of reproductive biology such as breeding systems, pollinators, and seed dispersers will also be assessed. The data generated in this study should provide guidelines for assessing the risk of extinction in the many endangered and threatened species endemic to oceanic islands, as well as for fragmented and small populations in contin ental areas. The proposed work will have a strong educational component because National Park guides on the islands, Chilean graduate students, and Chilean faculty members will receive training in various aspects of conservation biology.
