ROW/RIA: Interrelationships of Salamanders of the genus Ambystoma

这项拟议的研究将首次对鼹鼠火蜥属的进化关系进行全面分析。关系将通过测量线粒体DNA的遗传差异来确定。有了支持良好的系统发育树，人们可以研究与群体适应性辐射有关的生物地理因素。该研究的这一部分还将提供关于两栖动物线粒体DNA进化机制的信息，本研究中使用的这一组可能有助于确定许多其他生物系统的遗传关系。良好的系统发展史将为本研究的第二部分提供背景。鼹鼠属包括几个独特的克隆繁殖(单性)形式；这些形式起源于不同物种之间的杂交。在拟议研究的第二部分，线粒体DNA将用于分析克隆种群的遗传变异。这将提供有关克隆形式母系祖先的信息。它还将显示是否有很多或很少这样的起源，无论是最近的还是古代的。因此，人们将能够重建这些血统的历史--它们来自哪里，如何传播，何时传播，传播到什么程度。这样的进化史将为更详细地研究克隆生物的遗传机制提供必要的背景。

The proposed study will provide the first comprehensive analysis of evolutionary relationships in the genus Ambystoma, the mole salamanders. Relationships will be determined by measuring genetic differences in mitochondrial DNA. With a well supported phylogenetic tree, one can study the biogeographical factors involved in the adaptive radiation of the group. This part of the study will also provide information on the mechanisms of evolution of mitochondrial DNA in amphibians, a group for which to be used in this study may prove useful for determining genetic relationships in many other biological systems. A good phylogeny will provide the context for the second part of this study. The mole salamander genus includes several distinctive clonally reproducing (unisexual) forms; these originated by hybridization between different species of Ambystoma. In the second part of the proposed study, mitochondrial DNA will be used to analyze genetic variation in the clonal populations. This will provide information on the maternal ancestors of clonal forms. It will also show whether there were many or few such origins, recent or ancient. One will therefore be able to reconstruct a history of these lineages-- where did they come from, how, when, and to what extent did they spread. Such an evolutionary history will provide the necessary background for more detailed studies of the genetic mechanisms involved in producing clonal organisms.