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 Anseriformes Wagler, 1831 - waterfowl and screamers
                     Suborder Anseres Linnaeus, 1758 - waterfowl
                       Family Anatidae Vigors, 1825 - ducks, geese, swans
                         1 Genus Cygnus Bechstein, 1803 - mute swan
                         2 Genus Anser Brisson, 1760
                         3 Genus Branta Scopoli, 1769 - Canada goose
                         4 Genus Anas Linnaeus, 1758 - Pacific black duck
                         5 Genus Aythya Boie, 1822 - hardhead
                         6 Genus Somateria Leach, 1819
                         7 Genus Mergus Linnaeus, 1758
                         8 Genus Oxyura Bonaparte, 1828 - blue-billed duck