Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
   Subclass Neornithes Gadow, 1893 see Clade Neornithes Gadow, 1893
     Infraclass Eoaves Sibley et al., 1988 see Cohort Palaeognathae Pycraft, 1900
       Parvclass Ratitae (Merrem, 1813) see Subcohort Ratitae Merrem, 1813
         1 Order Struthioniformes Latham, 1790
         2 Order Tinamiformes Huxley, 1872