ATOL: Phylum Nematoda: Integrating Multidisciplinary Expertise and Infrastructure for Resolving Relationships in a Major Branch of the Tree of Life

新汉普郡大学的William K Thomas博士及其同事James Baldwin博士和Paul De Ley博士(加州大学河滨分校)、David Fitch博士(纽约大学)和Steven Nadler博士(加州大学戴维斯分校)被授予研究线虫的进化史和生物多样性。线虫门(蛔虫)被认为是地球上最丰富和遗传多样性的动物门之一。此外，它们在动物进化和理解有争议的无脊椎动物进化关系方面发挥着关键作用。这个庞大的门的系统发育研究一直受到处理如此多样化的分类群的困难的阻碍，这些分类群中的大多数是微观的，相对较少的专家知道。线虫的系统发育也受到不同学科之间分类学专家的分裂以及对经济或医学上重要的植物、脊椎动物和无脊椎动物寄生虫的偏见的阻碍。因此，了解它们的进化史是NSF组装生命树计划的关键组成部分。这个项目将为线虫开发一个更高层次的树，为解释它们的多样性提供一个框架。这项工作将使用1000多个物种的分子(18S核糖体基因)和形态数据。同时，他们将利用这项工作的结果作为选择50种线虫构建cDNA文库的基础，以更好地了解该门的遗传多样性，并可能解决有关线虫树最深的分支，甚至其在动物界的系统发育地位的长期存在的问题。

A grant has been awarded to Dr. William K Thomas at the University of New Hampshire and his colleagues Dr. James Baldwin and Dr. Paul De Ley (University of California, Riverside), Dr. David Fitch (New York University) and Dr. Steven Nadler (University of California, Davis) to examine the evolutionary history and biodiversity of nematodes. The phylum Nematoda (roundworms) is argued to be one of the most abundant and genetically diverse animal phyla on earth. In addition, they play a key position in animal evolution and understanding of controversial invertebrate evolutionary relationships. Phylogenetic studies of this enormous phylum have been impeded by the difficulty of working with such diverse taxa, most of which are microscopic and known by relatively few experts. Nematode phylogenetics has also been impeded by the fragmentation of taxonomic specialists among different disciplines and by bias toward economically or medically important parasites of plants, vertebrates and invertebrates. Accordingly, understanding their evolutionary history is a critical component in the NSF's Assembling the Tree of Life program. This project will develop a higher-level tree for the nematodes to provide a framework for interpreting their diversity. The work will use both molecular (18S ribosomal genes) and morphological data for over 1000 species. In a parallel effort, they will use the results of this work as a basis for selecting 50 nematode species for construction of cDNA libraries to provide greater insight into genetic diversity in the phylum and to possibly resolve the longstanding questions about of the deepest branches of the nematode tree or even its phylogenetic position in the animal kingdom.