Elephant (gianat) birds are members of the extinct family Aepyornithidae.
Elephant birds were large to enormous, flightless birds that once lived on the island of Madagascar, which lies about 420 km (260 mi) off the southeast coast of Africa. They became extinct, probably in the 17th or 18th century, for reasons that are unclear, although human activity is the suspected cause.
Elephant birds comprised the genera Mullerornis and Aepyornis. Aepyornis was among the heaviest of birds (the extinct Dromornis stirtoni of Australia reached a similar weight). While they were in close geographical proximity to the ostrich, elephant birds' closest living relatives are kiwis, arguing that * ratites did not diversify by **vicariance during the breakup of Gondwana but instead evolved from more recent ancestors that dispersed by flying.
* Ratites: a bird with a flat breastbone; especially : any of various mostly flightless birds (as an ostrich, rhea, emu, moa, or kiwi) with small or rudimentary wings and no keel on the sternum that are probably of polyphyletic origin and are assigned to a number of different orders.
** Vicariance is a process by which the geographical range of an individual taxon, or a whole biota, is split into discontinuous parts by the formation of a physical or biotic barrier to gene flow or dispersal.