Molecular Phylogeny and Evolution of Dasyurid Marsupials Based on Protamine P1 Genes

Dasyurid有袋类动物是澳大利亚和新几内亚的主要陆生食肉动物。这项拟议的研究将延续对dasyurid关系进行调查的丰富传统，这项研究始于近一个世纪前的基本解剖描述，最近又纳入了基因序列的直接比较。该项目在结合来自三个基因的信息方面开辟了新的领域，一个是来自线粒体基因组的快速和缓慢进化位点（分别是细胞色素b和12rDNA），另一个来自细胞核（鱼精蛋白P1）。精蛋白是精子细胞中包裹染色体DNA分子的短肽，其基因序列在阐明几种哺乳动物类群的关系方面被证明是有价值的。一旦收集了所有的dasyurid物种，这个基因数据库将完善我们对系统发育的估计，使有关dasyurid进化的具体问题能够得到解决。最重要的是，这些问题的答案是精确的。用于探测物种及其区域的共同进化关系（如果有的话）的新分析方法，以及重建祖先适应的方法，都是强大的，因为它们基于已知的系统发育。实际上，系统发生学是一个框架，它将生物多样性的近似生态学解释与最终的进化解释相结合。

9419907 Krajewski Dasyurid marsupials are the dominant terrestrial carnivores of Australia and New Guinea. The proposed study will continue the rich tradition of investigation into dasyurid relationshisp, one that began nearly a century ago with basic anatomical descriptions and has lately incorporated direct comparisons of gene sequences. The project breaks new ground in combining information from three genes, one rapidly and one slowing evolving locus from the mitochondrial genome (cytochrome b and 12rDNA, respectively), and one from the nucleus (protamine P1). Protamines are short peptides that package chromosomal DNA molecules in sperm cells, and their gene sequences have proven valuable in elucidating the relationships of several mammalian groups. Once assembled for all dasyurid species, this genetic database will refine our estimate of phylogeny to the point where specific questions about dasyurid evolution can be addressed. Most importantly, the answers to such questions can be made precise. New analytical procedures for detecting the coevolutionary relationships (if any) of species and their areas, as well as methods for reconstructing ancestral adaptations, are powerful because they operate on a known phylogeny. In effect, phylogeny is the framework for integrating, proximate, ecological explanations of biological diversity with their ultimate, evolutionary counterparts.