| Gaviiformes |
Podicipediformes, Procellariiformes |
Stresemann (1934); Verheyen (1959a, 1961); Storer (1956, 1971a, b) |
| Podicipediformes |
Gaviiformes, Pelecaniformes, Gruiformes, Heliornithidae, Phoenicopteridae |
Stresemann (1934); Verheyen (1959b, 1961); Tyler (1969); Olson (1985); Van Tuinen et al. (2001); Storer (2002); Mayr (2004a) |
| Pelecaniformes |
Polyphyly (multiple topologies) |
Beddard (1897); Chandler (1916); Simonetta (1963); Hedges & Sibley (1994); Bourdon, Boya & Iarochène (2005) |
| Balaenicipitidae |
Ciconiiformes, Pelecaniformes |
Parker (1860, 1861); Reinhardt (1860, 1862); Bartlett (1861); Giebel (1873); Beddard (1888); Shufeldt (1901a); Mitchell (1913); Böhm (1930); Cottam (1957); Feduccia (1977a); Cracraft (1985); Mayr (2003a); Mayr & Clarke (2003) |
| Scopidae |
Ciconiiformes, Pelecaniformes |
Beddard (1884); Shufeldt (1901a); Mayr (2003a) |
| Falconimorphae |
Polyphyly |
Fürbringer (1888); Gadow (1892); Sibley & Ahlquist (1990) |
| Cathartidae |
Falconiformes, Ciconiiformes |
Ligon (1967); Cracraft & Rich (1972); Emslie (1988); Avise, Nelson & Sibley (1994a); Helbig & Seibold (1995) |
| Phodilidae |
Tytonidae, Strigidae |
Milne-Edwards (1878a); Beddard (1890); Shufeldt (1900); Miller (1965); Hoff (1966); Marshall (1966) |
| Phoenicopteridae |
Anseriformes, Ciconiiformes, Charadriiformes |
Gadow (1877); Weldon (1883); Parker (1889a); Shufeldt (1889a, 1901b); Chandler (1916); Feduccia (1976, 1977b); Livezey (1997a, b, 1998a) |
| Turnicidae |
Gruiformes, Galliformes; indeterminate, basal Neornithines |
Parker (1862); Ogilvie-Grant (1889); Gadow (1893); Lowe (1923); Livezey (1998b); Rotthowe & Starck (1998) |
| Mesitornithidae |
Gruiformes, Cuculiformes |
Bartlett (1877); Milne-Edwards (1878b); Forbes (1882); Gadow (1893); Lowe (1924); Livezey (1998b); Mayr & Ericson (2004) |
| Pedionomidae |
Gruiformes, Charadriiformes |
Gadow (1891a); Bock & McEvey (1969); Olson & Steadman (1981); Livezey (1998b) |
| Rhynochetidae |
Ardeiformes, Gruiformes |
Bartlett (1862); Parker (1869); Murie (1871); Beddard (1891); Mitchell (1915); Steinbacher (1968); Livezey (1994, 1998b) |
| Opisthocomidae |
Tinamidae, Ratitae, Galliformes, Cuculiformes, Columbidae, Pteroclide, Rallidae, Otididae, Coliidae |
Perrin (1875); Garrod (1879); Von Nathusius (1881); Beddard (1889); Gadow (1891b); Parker (1891); Mitchell (1896); Shufeldt (1918); Böker (1929); Barnikol (1953); Parsons (1954); Verheyen (1956a); Sibley & Ahlquist (1973); Avise et al. (1994b); Hackett et al. (1995); Hedges et al. (1995); Hughes & Baker (1999); Johansson et al. (2001); Mayr & Clarke (2003); Sorenson et al. (2003) |
| Pteroclidae |
Columbiformes, Galliformes, Charadriiformes |
Parker (1862); Elliot (1878); Gadow (1882); Shufeldt (1901c); Chandler (1916); Stegmann (1957, 1959); Fjeldså (1976) |
| Caprimulgiformes |
Paraphyly or polyphyly, notably Aegothelidae, Steatornithidae |
Garrod (1873b); Shufeldt (1885); Beddard (1886); Parker (1889b); Bühler (1970); Johansson et al. (2001); Mayr (2002a) |
| Trochilidae |
Apodidae, Passeriformes |
Lowe (1939); Chandler (1916); Cohn (1968) |
| Coliidae |
Cuculiformes, Coraciiformes, Indicatoridae, Caprimulgiformes |
Murie (1872a); Garrod (1876); Verheyen (1956b); Sibley & Ahlquist (1972); Berman & Raikow (1982); Espinosa de los Monteros (2000) |
| Trogonidae |
Coliidae, Cuculiformes, Coraciiformes |
Forbes (1881); Espinosa de los Monteros (1998, 2000); Mayr (2003b) |
