Saetre G P, Borge T, Lindell J, Moum T, Primmer C R, Sheldon B C, Haavie J, Johnsen A, Ellegren H
Department of Evolutionary Biology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18d, SE-752 36 Uppsala, Sweden.
Mol Ecol. 2001 Mar;10(3):737-49. doi: 10.1046/j.1365-294x.2001.01208.x.
Evolutionary history of Muscicapidae flycatchers is inferred from nuclear and mitochondrial DNA (mtDNA) sequence comparisons and population genetic analysis of nuclear and mtDNA markers. Phylogenetic reconstruction based on sequences from the two genomes yielded similar trees with respect to the order at which the species split off. However, the genetic distances fitted a nonlinear, polynomial model reflecting diminishing divergence rate of the mtDNA sequences compared to the nuclear DNA sequences. This could be explained by Haldane's rule because genetic isolation might evolve more rapidly on the mitochondrial rather than the nuclear genome in birds. This is because hybrid sterility of the heterogametic sex (females) would predate that of the homogametic sex (males), leading to sex biased introgression of nuclear genes. Analyses of present hybrid zones of pied (Ficedula hypoleuca) and collared flycatchers (F. albicollis) may indicate a slight sexual bias in rate of introgression, but the introgression rates were too low to allow proper statistical analyses. It is suggested, however, that the observed deviation from linearity can be explained by a more rapid mutational saturation of the mtDNA sequences than of the nuclear DNA sequences, as supported by analyses of third codon position transversions at two protein coding mtDNA genes. A phylogeographic scenario for the black and white flycatcher species is suggested based on interpretation of the genetic data obtained. Four species appear to have diverged from a common ancestor relatively simultaneously during the Pleistocene. After the last glaciation period, pied and collared flycatchers expanded their breeding ranges and eventually came into secondary contact in Central and Eastern Europe and on the Baltic Isles.
通过对核DNA和线粒体DNA（mtDNA）序列的比较以及对核DNA和mtDNA标记的群体遗传分析，推断了鹟科捕蝇鸟的进化历史。基于两个基因组序列的系统发育重建产生了相似的树状图，显示了物种分化的顺序。然而，遗传距离符合非线性多项式模型，这反映出与核DNA序列相比，mtDNA序列的分歧率在降低。这可以用霍尔丹法则来解释，因为在鸟类中，遗传隔离可能在线粒体基因组上比在核基因组上进化得更快。这是因为异配性别（雌性）的杂种不育会早于同配性别（雄性），导致核基因的性别偏向渐渗。对斑姬鹟（Ficedula hypoleuca）和白领姬鹟（F. albicollis）当前杂交区的分析可能表明渐渗率存在轻微的性别偏差，但渐渗率过低，无法进行适当的统计分析。然而，有人认为，观察到的与线性的偏差可以用mtDNA序列比核DNA序列更快的突变饱和来解释，这得到了对两个蛋白质编码mtDNA基因第三密码子位置颠换分析的支持。基于对所获得遗传数据的解释，提出了黑白捕蝇鸟物种的系统地理学情景。四个物种似乎在更新世期间相对同时地从一个共同祖先分化出来。在上一个冰川期之后，斑姬鹟和白领姬鹟扩大了它们的繁殖范围，并最终在中欧、东欧和波罗的海岛屿上再次接触。
