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 Strigiformes Wagler, 1830 - owls
                     Family Strigidae Vigors, 1825 - owls
                       1 Genus Otus Pennant, 1769
                       2 Genus Bubo Duméril, 1806
                       3 Genus Glaucidium Boie, 1826
                       4 Genus Ninox Hodgson, 1837
                       5 Genus Strix Linnaeus, 1758
                       6 Genus Asio Brisson, 1760