|Diversity map of Accipitriformes (258 species). The colour gradient (from light to dark) indicates species richness.|
For a long time, the majority view was to include them with the falcons in the Falconiformes. However, a recent DNA study has shown that falcons are not closely related to the Accipitriformes. Instead, they are related to parrots and passerines.
Since then putting the falcons next to the parrots in taxonomic order has been adopted by most ornithologists. The DNA-based proposal includes the New World vultures in the Accipitriformes, but the American Ornithologists' Union (AOU) classifies the New World vultures as a separate order, the Cathartiformes.
- Nagy, Jenő (2020). "Biologia Futura: rapid diversification and behavioural adaptation of birds in response to Oligocene–Miocene climatic conditions" (PDF). Biologia Futura. 71 (1–2): 109–121. doi:10.1007/s42977-020-00013-9.
- Hackett S.J. et al 2008. A phylogenomic study of birds reveals their evolutionary history. Science 320 (5884): 1763–1768. 
- Remsen J.V. et al 2008. A classification of the bird species of South America (section ACCIPITRIDAE (HAWKS) 3, note 1). Version 11. American Ornithologists' Union.