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. |