The Ostrich Struthio camelus is the tallest bird in Australia, and is flightless, lacking a keel on the sternum. Individuals are characterised by their strong legs, feet that lack a hind toe (possessing only two forward facing toes), and loose barbless feathers. Males undertake nesting duties while the females are polygamous. The Ostrich occurred in isolated parts of Australia (occasional sightings still from Barham (-35.620789, 144.140736) as a result of released birds from captive populations that most closely resemble (mitochondrially) the eastern African populations.