Reconstructing Phylogenetic Frameworks Using Marsupials as a Test System, With Implications For Marsupial Biogeography and the Evolution of Morphological and Molecular Characters

小行星9419617 有袋目和有袋目之间的进化关系（例如：考拉、袋鼠、负鼠）已经被古生物学家、解剖学家、生理学家和生物化学家研究。然而，一些问题仍然没有答案，包括澳大利亚和美国分类群之间的关系。建议研究的是来自两个编码核糖体RNA的线粒体基因的DNA序列。 这项研究将评估分子与解剖数据在破译进化关系中的有用性。分子数据也将用于估计有袋类谱系之间的分歧时间。这些分歧时间将在已知的海平面变化和大陆板块在地质过去的运动的背景下进行评估，为有袋动物的早期进化发展一个动物地理学假说。在这项研究中产生的DNA序列数据库，结合已经可用于胎盘哺乳动物的序列（例如，啮齿动物、灵长类动物、鲸鱼、海豹），将允许详细研究哺乳动物核糖体RNA基因的进化。

9419617 Springer Evolutionary relationships among orders and families of marsupials (eg. koalas, kangaroos, opossums) have been studied by paleontologists, anatomists, physiologists and biochemists. However, a number of questions remain answered including relationships between Australian and American taxa. Proposed for study are DNA sequences from two mitochondrial genes that code for ribosomal RNAs. The study will evaluate the usefulness of molecular vs. anatomical data in deciphering evolutionary relationships. Molecular data will also be used to estimate divergence times among marsupial lineages. These divergence times will be evaluated in the context of what is known about sea level change and the movement of continental plates in the geologic past to develop a zoogeographic hypothesis for the early evolution of marsupials. The database of DNA sequences generated in this study, in conjunction with sequences that are already available for placental mammals (eg. rodents, primates, whales, seals) , will allow for detailed study of the evolution of ribosomal RNA genes in mammals.