Phylogeny and biogeography of dabbling ducks (genus : Anas): a comparison of molecular and morphological evidence

We constructed a phylogeny for the dabbling ducks (tribe Anatini) based on cytochrome-b and ND2 mitochondrial gene DNA sequences. This phylogeny diffe red in several important respects from a morphological phylogeny developed by Livezey (1991), including the distinctiveness of the blue-winged ducks f rom other dabbling ducks, the inclusion of the genus Tachyeres and exclusio n of Callonetta from the subtribe Anateae, and the lack of support for Mare ca as a genus separate from Anas. Characters from three other data sets sho wed greater consistency with the molecular topology than with the morpholog ical topology. The molecular phylogeny divides the dabbling ducks into four distinct groups: (1) four South American genera, including Amazonetta, Lop honetta, Speculanas, and Techyeres; (2) the Baikal Teal (Anas formosa); (3) the blue-winged ducks and allies; and (4) a large clade including wigeons, pintails, mallards, and several teal lineages. An examination of the distr ibutions of species in light of the phylogeny indicates relatively little b iogeographic structure. Geographic origin for most internal branches is amb iguous using several reconstruction methods. We suggest that the high dispe rsal ability of birds (especially dabbling ducks) has important implication s for recovery of branches using molecular systematics.