Philippe H, Germot A, Moreira D
Equipe Phylogénie, Bioinformatique et Génome, UMR CNRS 7622, 9 quai Saint-Bernard, Case 24 75252, Paris Cedex 05, France.
Curr Opin Genet Dev. 2000 Dec;10(6):596-601. doi: 10.1016/s0959-437x(00)00137-4.
Molecular phylogeny has been regarded as the ultimate tool for the reconstruction of relationships among eukaryotes-especially the different protist groups-given the difficulty in interpreting morphological data from an evolutionary point of view. In fact, the use of ribosomal RNA as a marker has provided the first well resolved eukaryotic phylogenies, leading to several important evolutionary hypotheses. The most significant is that several early-emerging, amitochondriate lineages, are living relics from the early times of eukaryotic evolution. The use of alternative protein markers and the recognition of several molecular phylogeny reconstruction artefacts, however, have strongly challenged these ideas. The putative early emerging lineages have been demonstrated as late-emerging ones, artefactually misplaced to the base of the tree. The present state of eukaryotic evolution is best described by a multifurcation, in agreement with the 'big bang' hypothesis that assumes a rapid diversification of the major eukaryotic phyla. For further resolution, the analysis of genomic data through improved phylogenetic methods will be required.
鉴于从进化角度解释形态学数据存在困难，分子系统发育学已被视为重建真核生物（尤其是不同原生生物类群）之间关系的终极工具。事实上，将核糖体RNA用作标记物已得出首个解析良好的真核生物系统发育树，从而产生了若干重要的进化假说。其中最重要的假说是，几个早期出现的、无线粒体的谱系是真核生物进化早期的现存遗迹。然而，使用替代蛋白质标记物以及对若干分子系统发育重建假象的认识，强烈挑战了这些观点。那些假定的早期出现的谱系已被证明是后期出现的，只是被人为错误地置于树的基部。真核生物进化的当前状态最好用多歧分支来描述，这与假设主要真核生物门类快速多样化的“大爆炸”假说一致。为了进一步解析，将需要通过改进的系统发育方法对基因组数据进行分析。
