Why do flightless birds such as ostrich and emu have wings?
R. KESAVAN Chennai Flightless birds are grouped under Ratitae. Generally ratites are large which have independently lost the ability to fly. These birds are found in South America, South Africa, New Zealand and Australia. They are quoted as example for discontinuous distribution. This discontinuity is believed to have happened millions of years ago due to continental drift. It is believed by scientists that the most flightless birds evolved in the absence of predators on islands and lost the power of flight, because they had few enemies, although this is likely not the case for ostrich, emu and cassowary as all have claws on their feet/wings to use as a weapon against predators. Many ratites live on isolated oceanic islands where there are no predators. Structurally these birds’ sternum (breast bone) is without keel to which flight muscles could be anchored. All species of ratites are thus unable to fly. They have more feathers than flying birds. The wings of these birds may be conside
