"Wisdom begins with putting the right name on a thing"
(Old Chinese Proverb)

Orders of Birds

DRAFT, 4/01/2017

The revised sequence of Orders previewed here is a step towards our goal of an evolutionary phylogeny of the major groups of birds. Our  policy  is to change higher level classification and sequences of taxa cautiously and conservatively.

Improving sets of DNA sequences and analytical approaches are  revolutionizing the Avian Tree of Life.  and call for substantial revisions of  the higher classification of birds, especially the sequence of the Orders (Hackett et al. 2008, Cracraft 2013, Jarvis et al. 2014, Prum et al. 2015, Suh et al. 2015). The consensus-based Avian Tree of Life, however,  includes up to 9 hard polytomies at its base   Their sequence in a linear classification awaits resolution.

Proposed reclassifications are summarized below.  Our goal is to revise the IOC Master List in late 2017 after final review.

 PALEOGNATHAE Ratites The ratites (paleognaths) are the sister group to the rest of living birds.
 Struthioniformes Ostriches
 Rheiformes Rheas
 Apterygiformes Kiwis Kiwis are sister to tinamous/emus+cassowaries (Cracraft 2013, Prum et al. 2015).
 Casuariiformes Emu, cassowaries
 Tinamiformes Tinamous Tinamou relationships within the ratites are uncertain (Hackett et al. 2008,  Baker et al. 2010, Haddrath and Baker 2012), but are treated provisionally as sister to emus, cassowaries (Prum et al. 2015).
 NEOGNATHAE
GALLOANSERES Landfowl (Galliformes) and Waterfowl (Anseriformes) together (Galloanseres) are sister to all other extant non-paleognath birds (Neoaves).
 Galliformes Landfowl: Grouse, quail, pheasants, francolins, guineafowl, moundbuilders A basal lineage of the Neognathae, Landfowl (Galliformes) are sister to the Waterfowl (Anseriformes).
 Anseriformes Waterfowl: Ducks, geese, swans, screamers Waterfowl (Anseriformes) are sister to the Landfowl (Galliformes).
NEOAVES Neoaves includes three major components: (1) a basal unresolved polytomy of at least 9 Orders, (2) a Core Waterbird Clade (Aequornithes) and (3) a Core Landbird Clade (Telluraves) (Prum et al. 2015, Suh et al. 2016).
 Caprimulgiformes Nightjars, frogmouths, potoos, oilbirds, owlet-nightjars, swifts, hummingbirds Propose to merge Apodiformes, including owlet-nightjars as well as swifts and hummingbirds, with the Caprimulgiform nightbirds to define a  spectacular basal adaptive radiation of Neoaves.
Musophagiformes Turacos Turacos (Musophagiformes) are sister to cuckoos (Cuculiformes) (Jarvis et al. 2014, Prum et al. 2015).
 Otidiformes Bustards Move bustards (Otididae) from the Gruiformes to their own Order, the Otidiformes, related to turacos (Musophagiformes) and cuckoos (Cuculiformes) (Hackett et al. 2008, Jarvis et al. 2014, Prum et al. 2015).
 Cuculiformes Cuckoos Cuckoos (Cuculiformes) are sister to turacos (Musophagiformes) and bustards (Otidiformes) (Jarvis et al. 2014, Prum et al. 2015)
 Mesitornithiformes Mesites Move mesites (Mesitornithidae) from the Gruiformes to their own Order, the Mesitornithiformes (Hackett et al. 2008). Mesites are sister to sandgrouse (Pterocliformes) and in turn pigeons (Columbidae) (Hackett et al. 2008, Jarvis et al. 2014, Prum et al. 2015).
 Pterocliformes Sandgrouse Sandgrouse (Pterocliformes) are sister to the Malagasy mesites (Hackett et al. 2008, Jarvis et al. 2014, Prum et al. 2015).
 Columbiformes Pigeons Pigeons (Columbiformes) are the sister group to an Old World clade consisting of sandgrouse (Pterocliformes) and the  mesites (Mesitornithiformes). Together they form the clade Columbimorphae at or near the base of Neoaves (Hackett et al. 2008, Jarvis et al. 2014, Prum et al. 2015).
 Gruiformes Diverse terrestrial and marshbirds: rails, coots, flufftails, sungrebes, cranes, limpkin, buttonquails, trumpeters Long recognized to be an artificial assemblage of taxa, the core Gruiformes is now restricted to flufftails, finfoots, rails, trumpeters, cranes, and Limpkin (Hackett et al. 2008, Prum et al. 2015).
Podicipediformes Grebes Grebes and flamingos are ancient sister taxa and members of the basal polytomy, potentially related to shorebirds (Charadriiformes) (Hackett et al. 2008, Mayr 2008, Prum et al. 2015).
 Phoenicopteriformes Flamingos Flamingos and grebes are ancient sister taxa, potentially related to shorebirds (Charadriiformes) (Hackett et al. 2008, Mayr 2008, Prum et al. 2015).
 Charadriiformes Shorebirds and relatives: sandpipers, plovers,phalaropes, stilts, jacanas, painted snipes, pratincoles, gulls and terns, seedsnipes, sheathbills, skimmers, skuas, auks Shorebirds and diving birds included traditionally in the Charadriiformes are an ancient clade and member of the unresolved basal polytomy.
 Eurypygiformes Sunbittern, Kagu The Kagu (Rhynochetidae) and Sunbittern (Eurypygidae) are removed from the Gruiformes to a new Order Eurypygiformes (Hackett et al. 2008), which (with tropicbirds Phaethontiformes) is sister to the Core Waterbird clade (Prum et al. 2015).
 Phaethontiformes Tropicbirds Tropicbirds are sister (with Sunbittern) to Core Waterbird clade (Prum et al. 2015).
Aequornithes Core Waterbirds (Prum et al. 2015, Suh 2016)
 Gaviiformes Loons Loons are the outgroup to penguins (Sphenisciformes) + tube-nosed seabirds (Procellariiformes) (Prum et al. 2015).
 Sphenisciformes Penguins Penguins (Sphenisciformes) are sister to the tube-nosed seabirds (Procellariiformes).
 Procellariiformes Tube-nosed seabirds: petrels, shearwaters, albatrosses, storm petrels, diving petrels. The tube-nosed seabirds (Procellariiformes) are sister to penguins (Sphenisciformes).  Albatrosses are  the sister group to all other tubenoses (Prum et al. 2015, cf Hackett et al. 2008).
 Ciconiiformes Storks  The Order Ciconiiformes includes only the storks (Ciconiidae). Ibises and spoonbills (Threskiornithidae) and herons (Ardeidae) are members of the Pelecaniformes (Hackett et al. 2008, Jarvis et al. 2014, Prum et al. 2015).
 Suliformes Frigatebirds, cormorants, anhingas, boobies  The totipalmate water and diving birds (Suliformes) are sister to the wading birds (ibis, herons) and pelican allies (Pelecaniformes) (Prum et al. 2005).
 Pelecaniformes Ibis, herons, pelican,  Hammerkop, Shoebill  The relationships among groups in the terminal waterbird clade (Pelecaniformes) differ among analyses (Hackett et al. 2008, Prum et al. 2015).
Opisthocomiformes Hoatzin The Hoatzin (Opisthocomiformes) is one of the most ancient, living bird lineages (Prum et al. 2015).
Telluraves
 Accipitriformes Raptors incl Cathartiformes  Raptors (Accipitriformes) are a basal member of the Core Landbird clade Telluraves. New World vultures are deep basal split and sister to the rest of the Accipitriformes (Prum et al. 2015).  SACC elevates the New World Vultures (Cathartidae) to a separate order, the Cathartiformes.
 Strigiformes Owls  Owls (Strigiformes) and raptors (Accipitriformes) are basal members of the Core Landbirds.
Coliiformes Mousebirds  Mousebirds (Coliiformes) are basal members of the Core Landbirds.
 Leptosomiformes Cuckoo Roller  The Cuckoo Roller is the only member of an ancient lineage  with no known relatives among modern birds and thus put into a separate Order. Leptosomiformes distantly related to mousebirds and trogons among other Core Landbirds (Hackett et al. 2008, Prum et al. 2015).
 Trogoniformes Trogons, quetzals Trogons (Trogoniformes) are embedded in the Core Landbirds (Prum et al. 2015).
 Bucerotiformes Hornbills, hoopoes, wood hoopoes Separation of the hoopoes and hornbills from the Coraciiformes as the Order Bucerotiformes maintains monophyly of the Coraciiformes (Hackett et al. 2008, Prum et al. 2015).
 Coraciiformes Kingfishers and allies: todies, motmots, bee-eaters The Coraciiformes (sensu stricto) is the sister group to the monophyletic Piciformes (Prum et al. 2015).
 Piciformes Woodpeckers and allies The diverse, monotypic and traditional Piciformes includes honeyguides, wrynecks, barbets and toucans as well as woodpeckers worldwide (Hackett et al. 2008, Prum et al. 2015).
 Cariamiformes Seriamas Move seriemas (Cariamidae) from the Gruiformes to their own Order, the Cariamiformes, related in turn to the terminal landbird clade Australaves  (Hackett et al. 2008, Jarvis et al. 2014, Prum et al. 2015).
 Falconiformes Falcons The falcons and caracaras (Falconiformes) are not relatives of the Accipitriformes, but rather a separate lineage and Order in the terminal landbird clade Australavis which includes parrots and in turn the Passeriformes (Hackett et al. 2008, Jarvis et al. 2014, Prum et al. 2015). See Fuchs et al. 2015 for phylogeny of falcons.
 Psittaciformes Parrots Parrots (Psittaciformes) are the sister group to the Passeriformes (Hackett et al. 2008, Jarvis et al. 2014, Prum et al. 2015).
 Passeriformes Perching birds The Passeriformes, or perching birds, include the majority of world bird species. The New Zealand Wrens (Acanthisittidae) are the sister group to all passerines, including both suboscines and oscines.