Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
   Subclass Neornithes Gadow, 1893 see Clade Neornithes Gadow, 1893
     Infraclass Neoaves Sibley et al., 1988 see Subcohort Neoaves Sibley et al., 1988
       Parvclass Passerae see Superorder Passerimorphae Sibley et al., 1988
         1 Superorder Cuculimorphae Sibley et al., 1988
         2 Superorder Psittacimorphae Huxley, 1867
         3 Superorder Apodimorphae see Order Apodiformes Peters, 1940
         4 Superorder Strigimorphae see Superorder Falconimorphae Seebohm, 1890
         5 Superorder Passerimorphae Sibley et al., 1988