Multilocus Tests of Speciation Models and Comparative Phylogeography of Australian Birds

scott V. EdwardsPeter beera博士获得了一项资助。华盛顿大学的Scott Edwards和Peter Beerli利用分子遗传学工具来研究澳大利亚鸟类的进化。具体来说，该项目将使用遗传数据来推断：(1)在地质时代，一系列鸟类物种何时跨越澳大利亚北部重要的生态屏障——木匠屏障；(2)澳大利亚这一系列现代鸟类的祖先物种的种群规模；(3)分布在这一屏障上的鸣禽种群之间的遗传差异程度。这项研究将利用这些鸟类基因组中许多不同位置的一类被称为单核苷酸多态性（SNPs）的分子遗传标记中的DNA序列变异，以及新的统计方法来进行这些推断。这个项目意义重大，因为它将有助于弄清在一个孤立的大陆（澳大利亚）上鸟类多样化的时间和地点，从而有助于与其他大陆上鸟类和其他动物的多样化进行比较。这个项目将区分关于现代动物物种起源的两种相互竞争的理论，其中一种理论认为，这种分化大部分发生在最近，不到200万年前，另一种理论认为，这些分化事件可能发生得更早。研究结果将有助于记录生物多样化的全球模式，将这些模式与环境变化联系起来，从而为保护甚至预测进化历史提供历史背景。此外，这些数据将提供澳大利亚鸟类物种遗传变异数量的测量方法，从而提供一个可以比较其他物种（包括人类）遗传变异的标准。

DEB-0108249Scott V. EdwardsPeter BeerliA grant has been awarded to Drs. Scott Edwards and Peter Beerli at the University of Washington to apply molecular genetic tools to study the evolution of Australian birds. Specifically, the project will use genetic data to make inferences about (1) when in geological time a series of avian species diverged across an important ecological barrier in northern Australia, the Carpentarian barrier; (2) the size of the populations of the ancestral species from which this series of present-day bird species in Australia arose; and (3) the magnitude of genetic differences between populations of songbirds distributed across this barrier. The research will use DNA sequence variation in a class of molecular genetic markers known as single-nucleotide polymorphisms (SNPs) at many different places in the genomes of these birds, as well as novel statistical methods, to make these inferences.This project is significant because it will help clarify the timing and places of diversification of birds on an isolated continent (Australia), and thereby will facilitate comparisons with diversification of birds and other animals on other continents. This project will distinguish between two competing theories for the origin of current-day animal species, one of which says that much of this divergence took place very recently, less than 2 million years ago, the other of which, says that these divergence events probably took place much earlier. The results will help document global patterns of biological diversification, relate these patterns to environmental change, and thereby provide an historical context for conserving and even predicting evolutionary history. In addition, the data will provide measures of the amount of genetic variation within Australian bird species, thereby providing a gauge by which the genetic variability found in other species, including humans, can be compared.