cassowary (kăsˈəwârˌē) [key], common name for a flightless, swift-running, pugnacious forest bird of Australia and the Malay Archipelago, smaller than the ostrich and emu. The plumage is dark and glossy and the head and neck unfeathered, wattled, and brilliantly colored, with variations in the coloring in different species. The head bears a horny crest. The female is larger than the male, though both sexes are similar in color. They are monogamous and nest in shallow nests of leaves on the ground in forests. Only the male incubates the female's three to six dark-green eggs. Cassowaries are primarily nocturnal. Their diet consists mainly of fruits and berries, although some eat insects and small animals. Cassowaries are notoriously vicious and have attacked and killed men with their sharp, spikelike toenails. They are fast runners, attaining speeds up to 30 mi (48 km) per hr. Cassowaries are classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Struthioniformes, family Casuariidae.