Other members of the group include rheas, emus, cassowaries and the largest bird ever, now extinct, Aepyornis. Ostriches have very long necks and legs and are capable of running at about 65 km/h (40 mph).
Their feathers do not function as airfoils, but the plumes used to be very popular as ornaments in ladies' hats and such. Ostriches are large enough for a small human to ride them and have been used in some areas of northern Africa and Arabia as racing mounts.
In popular mythology, the Ostrich is famous for hiding its head in the sand at the first sign of danger. There have been no recorded observations of this behaviour, although the birds are known to lay their head and neck on the ground to appear less conspicuous when predators are near. When threatened, ostriches can seriously injure with kicks from their powerful legs.
Ostriches are noted for communal nesting, where a number of females will lay their eggs in a single nest, to be incubated by the male. The Ostrich's egg is the largest of all eggs.