RUI: Systematics and Genetic Biogeography of Mielichhoferia (Bryopsida)

9419772 Shaw对新环境的进化适应的一些比较引人注目的例子包括苔藓，特别是那些生长在矿山尾矿和其他富含矿物的基质上的物种。伊萨卡学院（Ithaca College）的乔纳森·肖（Jonathan Shaw）博士在几名本科生的帮助下，正在研究Mielichhoferia藓属（即所谓的铜藓）北部物种的种群和物种水平的遗传变异，目的是了解这四种北部物种在北美和欧洲目前分布的历史和生态控制。除了该植物的小配子体和孢子体阶段的形态特征外，肖博士还通过蛋白质电泳分析等位基因位点的变异，并将增加叶绿体DNA变异分析的新数据。先前的研究已经证明了苔藓物种个体群体中独特的标记等位基因，从而可以研究历史迁移路径和物种之间可能的杂交。尽管在自然界中发现的主要营养（配子体）阶段具有有趣的单倍体性质，但对近缘种间的遗传变异模式研究甚少。这项研究提出了几个具有挑战性的对比：广泛分布的分类群和狭窄限制的分类群，遗传变异性广泛的分类群和遗传变异性有限的分类群，生殖隔离的分类群和可能与近亲杂交的分类群。

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.