Ratite birds
(ostrich & allies)
Taxonomic families: 6
Extant species: 59

Galliformes
(grouse, quail, & allies)
Taxonomic families: 5
Extant species: 282

Anseriformes
(ducks, geese, & swans)
Taxonomic families: 3
Extant species: 162

Sphenisciformes
(penguins)
Taxonomic families: 1
Extant species: 17

Gaviiformes
(loons)
Taxonomic families: 1
Extant species: 5

Procellariiformes
(tube-nosed seabirds)
Taxonomic families: 4
Extant species: 112

Podicipediformes
(grebes)
Taxonomic families: 1
Extant species: 22

Phoenicopteriformes
(flamingos)
Taxonomic families: 1
Extant species: 5

Ciconiiformes
(storks, herons, & allies)
Taxonomic families: 3
Extant species: 116

Pelecaniformes
(pelicans & allies)
Taxonomic families: 8
Extant species: 65

Falconiformes
(hawks, eagles, & allies)
Taxonomic families: 3
Extant species: 304

Gruiformes
(cranes, rails, & allies)
Taxonomic families: 12
Extant species: 220

Charadriiformes
(gulls, shorebirds, & allies)
Taxonomic families: 17
Extant species: 466

Columbiformes
(pigeons & doves)
Taxonomic families: 1
Extant species: 308

Psittaciformes
(parrots & allies)
Taxonomic families: 1
Extant species: 364

Musophagiformes
(turacos & louries)
Taxonomic families: 1
Extant species: 23

Cuculiformes
(cuckoos, anis, & allies)
Taxonomic families: 1
Extant species: 138

Strigiformes
(owls)
Taxonomic families: 2
Extant species: 195

Caprimulgiformes
(nightjars & allies)
Taxonomic families: 5
Extant species: 119

Apodiformes
(hummingbirds & swifts)
Taxonomic families: 3
Extant species: 430

Coliiformes
(mousebirds)
Taxonomic families: 1
Extant species: 6

Trogoniformes
(trogons)
Taxonomic families: 1
Extant species: 40

Coraciiformes
(kingfishers, motmots, & allies)
Taxonomic families: 11
Extant species: 209

Piciformes
(woodpeckers, puffbirds, & allies)
Taxonomic families: 5
Extant species: 420

Passeriformes
(perching birds)
Taxonomic families: 97
Extant species: >6000

Opisthocomiformes
(hoatzin)
Taxonomic families: 1
Extant species: 1