Cas′sowary, a large running bird, native to New Guinea and northeastern Australia. Although related to the ostrich, it belongs to a different family and lives in dense forests, while the ostrich lives on open plains and deserts. It has black plumage, with a naked neck, and bright-colored (red, blue, yellow) wattles. It is about five feet high, with rudimentary wings, a swift runner and a good swimmer. On the head is a hard bony cap or helmet. The head is carried low while running, and the vines and branches strike this cap and slide over the back. It feeds mostly at night on fruits and berries. The birds may be tamed. If teased, they kick powerfully sideways.