[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Kingdom Animalia Linnaeus, 1758 - animals
     Branch Eumetazoa Butschli, 1910 see [unranked] Eumetazoa Bütschli, 1910
       Division Bilateria Hatschek, 1888 see Subkingdom Bilateria Hatschek, 1888
         Subdivision Deuterostomia Grobben, 1908 see Infrakingdom Deuterostomia Grobben, 1908
           Phylum Chordata Bateson, 1885 - chordates
             Subphylum Vertebrata Cuvier, 1812 - vertebrates
               Superclass Tetrapoda Goodrich, 1930 - tetrapods see Clade Tetrapoda Hatschek & Cori 1896 [Gauthier, Kluge & Rowe 1988]
                 Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
                   Subclass Neornithes Gadow, 1893 see Clade Neornithes Gadow, 1893
                     Superorder †Odontognathae Wetmore, 1930 see Subclass Archaeornithes Gadow, 1893
                       Genus †Hesperornis Marsh, 1872
                       Genus †Ichthyornis Marsh, 1872