This article lists living orders and families of birds. The links below should then lead to family accounts and hence to individual species.
The passerines (perching birds) alone account for well over 5,000 species. 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.[1]
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)[2] with some clade names after Yuri, T. et al. (2013).[3]
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.[6][7]
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.
^Barrowclough, GF; Cracraft, J; Klicka, J; Zink, RM (2016). "How Many Kinds of Birds Are There and Why Does It Matter?". PLOS ONE. 11 (11): e0166307. Bibcode:2016PLoSO..1166307B. doi:10.1371/journal.pone.0166307. PMC 5120813. PMID 27880775.
^Jarvis, E.D.; et al. (2014). "Whole-genome analyses resolve early branches in the tree of life of modern birds". Science. 346 (6215): 1320–1331. Bibcode:2014Sci...346.1320J. doi:10.1126/science.1253451. PMC 4405904. PMID 25504713.
^Yuri, T.; et al. (2013). "Parsimony and Model-Based Analyses of Indels in Avian Nuclear Genes Reveal Congruent and Incongruent Phylogenetic Signals". Biology. 2 (1): 419–444. doi:10.3390/biology2010419. PMC 4009869. PMID 24832669.
^Boyd, John (2007). "NEORNITHES: 46 Orders" (PDF). John Boyd's website. Retrieved 30 December 2017.[unreliable source?]
^Worthy, T.H.; Degrange, F.J.; Handley, W.D.; Lee, M.S.Y. (2017). "The evolution of giant flightless birds and novel phylogenetic relationships for extinct fowl (Aves, Galloanseres)". Royal Society Open Science. 11 (10): 170975. Bibcode:2017RSOS....470975W. doi:10.1098/rsos.170975. PMC 5666277. PMID 29134094.
^Hackett, S.J.; et al. (2008). "A Phylogenomic Study of Birds Reveals Their Evolutionary History". Science. 320 (5884): 1763–1768. Bibcode:2008Sci...320.1763H. doi:10.1126/science.1157704. PMID 18583609. S2CID 6472805.
^Yuri, T (2013). "Parsimony and model-based analyses of indels in avian nuclear genes reveal congruent and incongruent phylogenetic signals". Biology. 2 (1): 419–44. doi:10.3390/biology2010419. PMC 4009869. PMID 24832669.