Kingdom [Animalia] Linnaeus, 1758 - animals
   Subkingdom Metazoa Haeckel, 1874 see Kingdom Animalia Linnaeus, 1758
     Division Eumetazoa Butschli, 1910 see Subkingdom Eumetazoa Butschli, 1910
       Subdivision Bilateralia
         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
                 Order Pelecaniformes Sharpe, 1891
                   1 Family Phaëthontidae see Family Phaethontidae Brandt, 1831
                   2 Family Pelecanidae Rafinesque, 1815 - pelicans
                   3 Family Phalacrocoracidae Reichenbach, 1850 - cormorants
                   4 Family Anhingidae Reichenbach, 1849 - anhingas
                   5 Family Sulidae Reichenbach, 1849 - gannets, boobies
                   6 Family Fregatidae Degland & Gerbe, 1867 - frigatebirds