This order comprises a single family, Otididae (bustards).
Phylogeny of Otididae (bustards), with the distribution of each family being indicated by the colour-code used throughout this website (see Distribution code). The depicted cladogram is based on Cohen (2011), who didn´t provide a timescale.
Cohen, C. (2011), The phylogenetics, taxonomy and biogeography of African arid zone terrestrial birds: the bustards (Otididae),
sandgrouse (Pteroclidae),coursers (Glareolidae) and Stone Partridge (Ptilopachus), Ph.D. Dissertation, University of Cape Town. (pdf)
Yang, R., X. Wu, P. Yan, X. Su, and B. Yang (2009) Complete mitochondrial genome of Otis tarda (Gruiformes: Otididae) and phylogeny of Gruiformes
inferred from mitochondrial DNA sequences, Mol. Biol. Rep. 37(7), 3057-3066. DOI: 10.1007/s11033-009-9878-7. (pdf)