Sequences analysed in this study are available at the EMBL database (Accession nos AJ298336–AJ298348 and AJ299592–AJ299711).
Speciation, introgressive hybridization and nonlinear rate of molecular evolution in flycatchers
Article first published online: 7 JUL 2008
Volume 10, Issue 3, pages 737–749, March 2001
How to Cite
Sætre, G.-P. , Borge, T., Lindell, J., Moum, T., Primmer, C. R., Sheldon, B. C., Haavie, J., Johnsen, A. and Ellegren, H. (2001), Speciation, introgressive hybridization and nonlinear rate of molecular evolution in flycatchers. Molecular Ecology, 10: 737–749. doi: 10.1046/j.1365-294x.2001.01208.x
- Issue published online: 7 JUL 2008
- Article first published online: 7 JUL 2008
- Received 4 June 2000; revision received 22 August 2000;accepted 22 August 2000
- Haldane’s rule;
- single nucleotide polymorphism
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.