Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
   Subclass Neornithes Gadow, 1893 see Clade Neornithes Gadow, 1893
     1 Infraclass Eoaves Sibley et al., 1988 see Cohort Palaeognathae Pycraft, 1900
     2 Infraclass Neoaves Sibley et al., 1988 see Subcohort Neoaves Sibley et al., 1988