Phylogenetics and Biogeography of Amazonian Spiny Rats, Genus Proechimys (Mammalia: Echimyidae)

9317685 Patton该提案要求资助研究南美洲热带森林啮齿动物属Proechimys的生物地理模式和物种形成过程的一系列相互关联的问题。这是一个大型的分类组合，由至少9个物种群和大约25个物种组成，但其中的物种边界是模糊的，也没有系谱关系的假设存在。作为新热带森林陆生小型哺乳动物群落中最丰富和分布最广泛的组成部分之一，这些老鼠为研究亚马逊盆地的生物地理历史以及确定该地区的分化过程提供了很大的希望。PI建议补充他正在进行的分析，强调颅齿形态，核学和蛋白质分子与线粒体DNA序列数据，以确定物种边界和物种群的系统发育重建。我们将采用酶法扩增DNA从细胞色素b编码基因，通过聚合酶链反应的方法。我们还将探讨核序列的效用，检查珠蛋白和醛缩酶基因家族的变异。重点将放在物种边界的确定和河流假设作为亚马逊盆地内多样化的力量的检验上。

9317685 Patton This proposal requests funding to examine a set of interrelated questions regarding the biogeographic patterns and speciation processes in the South American tropical forest rodent genus Proechimys. This is a large taxonomic assemblage, composed of at least nine species groups and approximately 25 species, but in which species boundaries are fuzzy and for which no hypothesis of genealogical relationships exists. As one of the most locally abundant and broadly distributed components of the terrestrial small mammal community of the Neotropical forests, these rats offer great promise as model organisms to examine the biogeographic history of the Amazon Basin, as well as to determine processes of divergence in that region. The PI proposes to complement his ongoing analyses that have emphasized craniodental morphology, karyology, and protein molecules with mitochondrial DNA sequence data for determination of species boundaries and phylogenetic reconstruction of the species groups. We will employ enzymatic amplification of DNA from the Cytochrome-b coding gene, via the polymerase chain reaction methodology. We will also explore the utility of nuclear sequences, examining variation in the globin and aldolase gene families. Emphasis will be placed on the determination of species boundaries, and on the examination of the riverine hypothesis as a force in diversification within the Amazon Basin.