Flightless bird Flightless bird Flightless birds are birds that through evolution lost the ability to fly. There are over 60 extant species including the well known ratites (ostrich, emu, cassowary, rhea and kiwi) and penguins. The smallest flightless bird is the Inaccessible Island rail (length 12.5 cm, weight 34.7 g). The largest (both heaviest and tallest) flightless bird, which is also the largest living bird, is the ostrich (2.7 m, 156 kg). Ostriches are farmed for their decorative feathers, meat and their skins, which are used to make leather. Many domesticated birds, such as the domestic chicken and domestic duck, have lost
Crotophaginae Crotophaginae The Crotophaginae are a small subfamily, within the cuckoo family Cuculidae, of four gregarious bird species occurring in the Americas. They were previously classified as a family Crotophagidae. The subfamily is notable for the development of cooperative breeding where several females lay eggs in a communal nest. It contains the three anis and the guira cuckoo. Among the anis, there is considerable variation in nesting habits. One species, The greater ani "C. major" lays 2 or 3 eggs, while the groove-billed ani "C. sulcirostris" lays seven. However the smooth-billed ani "C. ani" will share one nest between several females,