Parker A, Kornfield I
Department of Zoology, University of Maine, Orono, ME 04469, USA.
J Mol Evol. 1997 Jul;45(1):70-83. doi: 10.1007/pl00006204.
Considerable controversy has surrounded the application of mitochondrial DNA data to reconstruction of evolutionary relationships among the endemic cichlids of Lake Malawi. Central to this debate has been the issue of whether lineage sorting is complete, and thus whether these data actually reflect species phylogeny, or simply gene genealogy. Review of all mtDNA control region sequences available for members of one monophyletic subset of this species flock, the Malawi rockfishes, or mbuna, strongly indicates that lineage sorting is incomplete: Character-based analyses of these sequences reconstruct gene, not species, interrelationships. Analysis of the pattern of nucleotide substitutions differentiating these mtDNA alleles suggests that pyrimidine residues undergo transition substitutions more often than do purines. Estimation of the magnitude of derived sequence differentiation in light of the reconstructed gene genealogy suggests that the mbuna may be of considerably more recent vintage than previous molecular characterizations have indicated.
将线粒体DNA数据应用于重建马拉维湖特有丽鱼科鱼类的进化关系，这一做法引发了相当大的争议。这场争论的核心问题是谱系分选是否完成，进而这些数据是否真的反映了物种系统发育，还是仅仅反映了基因谱系。对该物种群的一个单系子集——马拉维岩鱼或mbuna成员的所有线粒体DNA控制区序列进行回顾，强烈表明谱系分选并不完整：基于特征对这些序列进行分析所重建的是基因而非物种的相互关系。对区分这些线粒体DNA等位基因的核苷酸替换模式进行分析表明，嘧啶残基比嘌呤残基更常发生转换替换。根据重建的基因谱系对衍生序列分化程度进行估计，结果表明mbuna的起源可能比之前分子特征分析所显示的要近得多。
