Chordata Bateson, 1885 - chordates
Count: -
   Vertebrata Cuvier, 1812 - vertebrates
  Count: -
     Homotherma
    Count: -
       Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
      Count: -
         Ornithurae Haeckel, 1866 see Clade Ornithurae Haeckel 1866 [Gauthier 1986] {Chiappe 1991}
        Count: -
           1 Ratitae (Merrem, 1813)
          Count: -
           2 Carinatae Merrem, 1813
          Count: -