有尾目是两栖动物的三大类群之一，包含了10科67属600多个物种，常被用做模式生物来研究胚胎学、发育生物学、生理学、解剖学、遗传学、动物行为、动物地理上的问题，而关于有尾目中不同分类单元间、各物种间的可靠的系统发育关系则是关键的背景知识，在这些研究中起着重要的指导作用。然而，关于有尾目动物内部系统发育关系目前还没有得到全面的阐明，其主要瓶颈在于缺少适用于两栖动物、数量足够的核基因分子标记。针对这一问题，本研究基于实验室前期的工作基础，计划为两栖动物开发30-50个高度通用的核基因分子标记，使之成为两栖动物分子系统学通用的分析工具集；同时，我们还会将这些核基因标记在有尾两栖类中进行实际应用，利用系统发育基因组学分析方法解决有尾两栖动物的3个主要系统发育问题（科级间关系、无肺螈科内部关系、小鲵科内部关系）,基本完成有尾两栖动物生命树的主干构建工作，推进两栖动物整体生命之树计划的完成。

Salamanders (Caudata), one of three major groups of living amphibians, comprise more than 600 extant species, most commonly grouped into 67 genera and 10 families. Because salamanders are often used as model systems to assess fundamental issues of morphological, developmental and biogeographical evolution, robust phylogenetic hypotheses concerning relationships among these animals are basic necessities. However, there is a lack of consensus regarding the stem tree of life for living salamanders, mostly because of insufficient data. The bottleneck is the lack of nuclear markers that can work with amphibians. To this end, based on our recent studies on marker screening and development, we plan to develop 30-50 nuclear markers, highly universal across all amphibian species, for amphibian phylogenomic studies. These new developed markers will be applied to resolve three important but unresolved phylogenetic questions of salamanders: the family-level relationships among living salamanders, the interrelationships within the family Plethodontidae, and the interrelationships within the family Hynobiidae. This project will provide an universal nuclear marker toolkit for future molecular systematic works on amphibians, construct a reliable stem tree for living salamanders, and accelerate the completion of the Amphibia Tree of Life.