Rapid radiation of canaries (genus Serinus)

Mitochondrial cytochrome b (mit cyt b) DNA from 20 out of 37 extant canarie s (genus Serinus) has been sequenced from living specimens photographed aro und the world. Phylogenetic analysis has consistently resulted in the same groupings of birds, which have generally been related to geographical proxi mity. The fossil registry of chicken and pheasant and its divergence time h ave been used to calibrate the molecular clock; mit cyt b DNA dendrograms s uggest that the Serinus bird lineage appeared in the Miocene (9 MYA), a tim e when the Mediterranean Sea was closing its western and eastern oceanic co nnections. Pleistocene,glaciations (starting 2 MYA) may have only been impo rtant in the subspeciation and isolation of birds in the Northern and South ern hemispheres around the world, and not only in North America, where it h as already been described. The European-isolated Serinus citrinella (Citril finch) is not a canary but rather a true goldfinch. Only about 4% average nucleotide divergence is found among the different Serinus species; this su ggests a remarkably rapid radiation when compared to other passerine (songb ird) genera radiations. In addition, reproductive barriers are observed bet ween closely related species but not between other more distant ones. Final ly, a tentative classification for the genus Serinus species is put forward .