COMPLETE MITOCHONDRIAL GENOME SEQUENCES AND THE PHYLOGENY OF CRANES (GRUIFORMES: GRUIDAE)

We estimated phylogenetic relationships among all 15 extant species of cranes in the gruiform family Gruidae from complete sequences of their mitochondrial genomes. The gene order of crane mitochondria I genomes corresponds to that of the chicken and present few structural novelties compared with previously described birds. Sequences of the control region, particularly domains I and III, are highly divergent among species and include tandem repeats, duplications, and numerous indels. Phylogenetic analyses confirmed the well-established, reciprocal monophyly of clades Balearicinae (crowned cranes) and Gruinae (anatomically derived cranes), as well as previously identified lineages within Gruinae: Leucogeranus and the species groups Anthropoides, Canadensis, Antigone, and Americana. As in previous molecular phylogenies, Leucogeranus is resolved as sister to all other gruines. In addition, the Sandhill Crane (Grus canadensis) is resolved as sister to the Antigone species group, resulting in a Pacific Rim clade that has not previously been suggested. Only relationships among the Anthropoides, Americana, and Pacific Rim groups remain unresolved in our analyses. The crane fossil record provides reasonable calibration points for the most recent common ancestor of Gruinae (Middle Miocene) and the minimum age of Grus americana (Late Pliocene). Bayesian estimates of divergence dates from mitochondrial DNA sequences suggest that balearicines and gruines separated in the late Oligocene and that radiations of living species within these clades took place in the Neogene. Received 25 June 2009, accepted 25 November 2009.