Phylum Chordata Bateson, 1885 - chordates
   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 Apodiformes Peters, 1940 - swifts
           1 Family Apodidae Hartert, 1897 - swifts
           2 Family Hemiprocnidae Oberholser, 1906 - treeswifts
           3 Family Trochilidae Vigors, 1825 - hummingbirds