This article lists living orders and families of birds. In total there are about 10,000 species of birds described worldwide, though one estimate of the real number places it at almost twice that. The order passerines (perching birds) alone accounts for well over 5,000 species. Taxonomy is very fluid in the age of DNA analysis, so comments are made where appropriate, and all numbers are approximate. In particular see Sibley-Ahlquist taxonomy for a very different classification.

Phylogeny

Cladogram of modern bird relationships based on Jarvis, E.D. et al. (2014) with some clade names after Yuri, T. et al. (2013).

Subclass Palaeognathae

The Palaeognathae or "old jaws" is one of the two superorders recognized within the taxonomic class Aves and consist of the ratites and tinamous. The ratites are mostly large and long-legged, flightless birds, lacking a keeled sternum. Traditionally, all the ratites were place in the order Struthioniformes. However, recent genetic analysis has found that the group is not monophyletic, as it is paraphyletic with respect to the tinamous, so the ostriches are classified as the only members of the order Struthioniformes and other ratites placed in other orders.

Order Struthioniformes

Africa; 2 species

Infraclass Notopalaeognathae

Order Rheiformes

South America; 2 species

Order Casuariiformes

Australasia; 4 species

Order Apterygiformes

Australasia; 5 species

Order †Aepyornithiformes

Madagascar

Order †Dinornithiformes

New Zealand

Order Tinamiformes

South America; 45 species

Subclass Neognathae

Nearly all living birds belong to the subclass Neognathae or "new jaws". With their keeled sternum (breastbone), unlike the ratites, they are known as carinatae.

Infraclass Galloanserae

Order Galliformes

Worldwide; 250 species

Order †Gastornithiformes

Order Anseriformes

Worldwide; 150 species

Superorder Mirandornithes

Order Podicipediformes

Worldwide; 19 species

Order Phoenicopteriformes

Worldwide; 6 species

Superorder Columbimorphae

Order Columbiformes

Worldwide; 300 species

Order Pterocliformes

Africa, Europe, Asia; 16 species

Order Mesitornithiformes

Madagascar; 3 species

Grandorder Cypselomorphae

Order Caprimulgiformes

Worldwide; 97 species

Order Steatornithiformes

South America; 1 species

Order Nyctibiiformes

Americas; 7 species

Order Podargiformes

Asia and Australasia; 14 species

Order Aegotheliformes

Australasia; 10 species

Order Apodiformes

Worldwide; 478 species

Grandorder Otidimorphae

Order Cuculiformes

Worldwide; 150 species

Order Musophagiformes

Africa; 23 species

Order Otidiformes

Africa and Eurasia; 27 species

Superorder Gruae

Order Opisthocomiformes

South America; 1 species

Order Gruiformes

Worldwide; 164 species

Order Charadriiformes

Worldwide; 350 species

Grandorder Phaethontimorphae

Order Eurypygiformes

Neotropics and New Caledonia; 2 species

Order Phaethontiformes

Oceanic; 3 species

Grandorder Aequornithes

Order Gaviiformes

North America, Eurasia; 5 species

Order Sphenisciformes

Antarctic and southern waters; 17 species

Order Procellariiformes

Pan-oceanic; 120 species

Order Ciconiiformes

Worldwide; 19 species

Order Suliformes

Worldwide; 59 species

Order Pelecaniformes

Worldwide; 108 species

Grandorder Afroaves

Order Accipitriformes

Worldwide; 260 species

Order Strigiformes

Worldwide; 250 species

Order Coliiformes

Sub-Saharan Africa; 6 species

Order Leptosomiformes

Madagascar; 1 species

Order Trogoniformes

Sub-Saharan Africa, Americas, Asia; 35 species

Order Bucerotiformes

Old World, New Guinea; 64 species

Order Coraciiformes

Worldwide; 144 species

Order Piciformes

Worldwide except Australasia; 400 species

Grandorder Australaves

Order Cariamiformes

South America; 2 species

Order Falconiformes

Worldwide; 60 species

Order Psittaciformes

Pan-tropical, southern temperate zones; 330 species

Order Passeriformes

Worldwide; 6,500 species