The emu (Dromaius novaehollandiae) is the largest bird native to Australia and the only extant member of the genus Dromaius. It is the second-largest extant bird in the world by height, after its ratite relative, the ostrich. There are three subspecies of emus in Australia. The emu is common over most of mainland Australia, although it avoids heavily populated areas, dense forest, and arid areas. The soft-feathered, brown, flightless birds reach up to 2 meters (6.6 ft) in height. They have long thin necks and legs. Emus can travel great distances at a fast, economical trot and, if necessary, can sprint at 50 km/h (31 mph). Their long legs allow them to take strides of up to 275 centimeters (9.02 ft)