RUI: Systematics and Genetic Biogeography of Mielichhoferia (Bryopsida)

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9419772 Shaw Some of the more spectacular cases of evolutionary adaptation to novel environments include the mosses, and in particular those species that grow on mine tailings and other substrates rich in mineral ores. Dr. Jonathan Shaw of Ithaca College, with assistance from several undergraduate students, is studying population and species-level genetic variation in northern species of the moss genus Mielichhoferia, so-called copper mosses, with the goal of understanding historical and ecological controls on the present distribution of the four northern species in North America and Europe. In addition to morphological features of the small gametophyte and sporophyte stages of the plant, Dr. Shaw is analyzing variation at allelic loci by protein electrophoresis, and will be adding new data from analysis of chloroplast DNA variation as well. Prior studies have demonstrated unique marker alleles of individual populations of the moss species, enabling study of the path of historical migration and of possible hybridization between species. The pattern of genetic variation among related species of mosses has been little studied, despite the interesting haploid nature of the major vegetative (gametophytic) stage found in nature. This study poses several challenging contrasts between widespread and narrowly restricted taxa, between species with wide genetic variability and those quite limited, and between reproductively isolated taxa and those potentially able to hybridize with relatives.