any member of a group of large, flightless birds that includes two families native to Australasia. The family Dromaiidae, made up of the single living species of emu (Dromaius novaehollandiae), is found only in Australia, whereas the family Casuariidae, made up of three species of cassowaries (Casuarius), is restricted to northern Australia, New Guinea, and nearby islands. Of the two groups, the emu is far better known, both biologically and popularly, being exhibited in zoos around the world. The common characteristics of emus and cassowaries are described in this article; however, most authorities place casuariiforms with ostriches, rheas, kiwis, and others in order Struthioniformes.
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