AVES | NEORNITHES | +-PALEOGNATHS | \-+--Struthioniformes | | \--Struthionidae (Ostriches) | | | \-+--Rheiformes | | \--Rheidae (Rheas) | | | \-+--+--+--Apterygiformes | | | | \--Apterygidae (Kiwis) | | | \-?Aepyornithiformes | | | \--Aepyornithidae (Elephant Birds) [extinct] | | | | | \--Casuariiformes | | \--+--Casuariidae (Cassowaries) | | \--Dromaiidae (Emus) | | | \-+--Dinornithiformes | | \--Dinornithidae (Moas) [extinct] | | | \--Tinamiformes | \--Tinamidae (Tinamous) | \-NEOGNATHS |--GALLOANSERAE | \--NEOAVES |--METAVES \--CORONAVES