Phylogenetic relationships and ancestral areas of the bustards (Gruiformes: Otididae), inferred from mitochondrial DNA and nuclear intron sequences

The taxonomy of the bustards is poorly understood phylogenetically and has not been extensively evaluated using molecular methods. We sequenced part of the mitochondrial cytochrome b gene, the control region (central domain II), and an intron-exon crossing fragment of the nuclear chromo-helicase-DNA binding gene (CHD1) in 27 bustard taxa (including multiple subspecies) representing 11 genera and four gruiform outgroup species. Molecular datings suggest a Miocene origin for the family. Inferred phylogenetic relationships include the following: (i) the basal polytomy consists of 10 branches (mostly consistent with traditional genera), suggesting a rapid early radiation; (ii) sister relationships between several couplets of genera include Ardeotis with Neotis, Afrotis with Eupodotis (excluding E. rueppellii), Otis with Chlamydotis, and Houbaropsis with Sypheotides; (iii) the genus Eupodotis may be polyphyletic; and (iv) the currently delimited genera Ardeotis and Neotis do not form independent monophyletic lineages. Molecular evidence for the Afro-tropical origin of the Otididae is provided.