Multilocus phylogeny and biogeography of the New World Pheucticus grosbeaks (Aves: Cardinalidae).

Using a multilocus approach, we investigated the tempo and pattern of diversification in a widely distributed New World songbird, the cardinalid genus Pheucticus. Each of the three geographic groups recovered (North American, Middle American, and South American) was comprised of a pair of currently recognized species, and four, three, and three geographically and genetically distinct phylogeographic lineages respectively. Diversification within Pheucticus appears to have occurred at a relatively constant pace throughout the Pleistocene and evenly across a broad latitudinal distribution. The Isthmus of Panama completion and Pleistocene glacial cycles both appear to have played prominent roles in the diversification of this group.