Probing Evolutionary Patterns in Neotropical Birds Through DNA Barcodes

KERR, KEVIN C. R.; LIJTMAER, DARÍO A.; BARREIRA, ANA S.; HEBERT, PAUL D. N.; TUBARO, PABLO L.

PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON. SERIES B: BIOLOGICAL SCIENCES.

Año: 2008

0962-8452

Do differing species ages or patterns of regional divergence explain the much higher diversity of Neotropical than Nearctic birds? Critical examination of these issues is currently constrained by the limited genetic information available, especially for the South American avifauna. This study begins to address this gap by assembling a library of mitochondrial COI sequences for Argentinian birds and comparing their patterns of genetic diversity to those of North American birds. Our results indicate that most Neotropical bird species show deep sequence divergence from their nearest-neighbour, indicating that the high diversity of this fauna is not based on an elevated incidence of young species radiations. The lack of shared polymorphisms in species, even in species with less than 0.5M years of reproductive isolation, further suggests that selective sweeps regularly excise ancestral mitochondrial polymorphisms. Although species ages appear similar in the North and South American avifaunas, patterns of regional divergence are more complex in the Neotropics, suggesting that the high diversity of the Neotropical avifauna has been fueled by greater opportunities for regional divergence.