Elephant birds were a group of large, flightless birds that lived in Madagascar. The genera *Elephantus*, *Elephantus mummie*, and *Elephantus maculata* comprised three genera, and they were extinct at least until the 16th century. Elephant birds were once considered the largest birds to have ever existed, reaching over three meters in height and weighing up to half a ton, until they were surpassed in October 2006 by fossils of the terror bird *Phorusrhacidae*. Adults and eggs of *Elephant birds* have been discovered, with some eggs having a long axis as long as one foot (34 cm). Currently, four species are classified under the genus *Elephant birds*: *A. childhoodbrandti*, *A. gracilis*, *A. medius*, and *A. maximus* (Brodkorb, 1963), but this classification is not entirely without controversy; some authors group them under the same species, *A. maximus*. Elephant birds belonged to the superorder *Palagnathae*, were more closely related to ostriches, were flightless, and lacked a keel on their sternum.
The National Geographic Society in Washington, D.C., displays a robin's egg discovered by Louis Madden in 1967. The egg is completely undamaged and contains the skeletal remains of an unhatched bird embryo.
The extinction of the elephant bird was related to humans, but not because they hunted it. Rather, it was because new immigrants from Madagascar continued to live a slash-and-burn lifestyle, constantly destroying forests to open up farmland, leaving less and less place for the elephant bird to inhabit.
In the afterword to Jin Yong's wuxia novel "The Return of the Condor Heroes", Jin Yong stated that the image of the "Condor" in the book was partly derived from the characteristics of the elephant bird.
