Betancur-R Ricardo, Ortí Guillermo
Department of Biological Sciences, The George Washington University, 2023 G St. NW, Washington, DC 20052, United States; Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, PO Box 37012, MRC 159, Washington, DC 20013-7012, United States.
Department of Biological Sciences, The George Washington University, 2023 G St. NW, Washington, DC 20052, United States.
Mol Phylogenet Evol. 2014 Apr;73:18-22. doi: 10.1016/j.ympev.2014.01.006. Epub 2014 Jan 18.
Proliferation of phylogenetic studies based on poor taxonomic sampling or insufficient molecular evidence usually leads to conflicting results. As a consequence, advancement of systematic knowledge yields to confusion. The problem is exacerbated for taxonomic groups with historically difficult resolution of evolutionary relationships such as the flatfishes. Molecular evidence to support monophyly for this emblematic group of fishes and their interrelationships has been elusive, and a recent paper published in this journal went as far as to claim that flatfish monophyly can be rejected with molecular data, implying that the asymmetric body plan unique to these fishes had two independent origins. A reanalysis of this evidence suggests the contrary and combination of the new data with existing datasets unequivocally supports the monophyly of this group based on analyses of concatenated data as well as species tree approaches. Resolution of difficult phylogenetic problems requires analysis of larger datasets with adequate taxonomic coverage and sound hypothesis-testing procedures. Proliferation of partial studies claiming extraordinary results should be avoided in order to advance the field of molecular phylogenetics.
基于分类抽样不足或分子证据不充分的系统发育研究激增，通常会导致相互矛盾的结果。因此，系统知识的进步反而导致了混乱。对于像比目鱼这样在历史上进化关系难以解析的分类群来说，问题更加严重。支持这一标志性鱼类群体的单系性及其相互关系的分子证据一直难以捉摸，最近发表在本杂志上的一篇论文甚至声称，比目鱼的单系性可以被分子数据否定，这意味着这些鱼类独特的不对称身体结构有两个独立的起源。对这一证据的重新分析表明情况恰恰相反，新数据与现有数据集的结合明确支持了基于串联数据分析和物种树方法的该类群的单系性。解决复杂的系统发育问题需要分析具有足够分类覆盖范围的更大数据集，并采用合理的假设检验程序。为了推动分子系统发育学领域的发展，应避免声称有非凡结果的局部研究激增。
