living organisms see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Superkingdom Eukaryotae see Domain Eukaryota Chatton, 1925
     Kingdom Animalia Linnaeus, 1758 - animals
       Subkingdom Eumetazoa Butschli, 1910 see [unranked] Eumetazoa Bütschli, 1910
         Phylum Chordata Bateson, 1885 - chordates
           Subphylum Vertebrata Cuvier, 1812 - vertebrates
             Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
               Subclass Neornithes Gadow, 1893 see Clade Neornithes Gadow, 1893
                 Superorder Neognathae Pycraft, 1900 see Cohort Neognathae Pycraft, 1900
                   Order Galliformes Temminck, 1820 - fowl
                     Family Tetraonidae Vigors, 1825
                       1 Genus Dendragapus Elliot, 1864
                       2 Genus Lagopus Brisson, 1760 - ptarmigan
                       3 Genus Tetrao Linnaeus, 1758
                       4 Genus Bonasa Stephens, 1819
                       5 Genus Centrocercus Swainson, 1832
                       6 Genus Tympanuchus Gloger, 1841