Ratites are a group of flightless birds that include the emu. Emus are large, flightless birds native to Australia and the only living members of the family Dromaiidae. They are the second-largest living bird by height, after the ostrich. Emus can travel great distances, and when necessary can sprint at 50 km/h (31 mph). They forage for a variety of plants and insects, but have been known to go for weeks without food.