Accipitriformes

Accipitriformes is an order which includes most of the diurnal birds of prey: hawks, eagles, vultures, and many others, about 225 species in all. 

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.Hackett S.J. et al 2008. A phylogenomic study of birds reveals their evolutionary history. Science 320 (5884): 1763–1768. 

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.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.  

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