Description and Taxonomy
Elephant birds were very large, approximately 10 feet tall and weighing around 880 pounds. Elephant bird egg remains have been found have a circumference of 3 feet 3 inches and up to 13 inches long.
Elephant birds were unable to fly and their breast bones had no keel, which is an extension of the sternum that runs perpendicular to the ribs. It helps birds that are able to fly, by providing them with adequate leverage.
Two entire elephant bird eggs have been found in southwestern Australia, although the birds only lived in Madagascar. They were eggs of Aepyornis maximus and are thought to have floated through the ocean from Madagascar to Australia. This happened before with penguin eggs from the Kerguelen Islands and an ostrich egg that was found floating in the Timor Sea.
There is not adequate fossil remains to determine what elephant birds ate but it is thought that they fed on certain fruits found within the jungles of Madagascar.
Genera and Species
There were two genera of elephant birds; Aepyornis and Mullerornis. In the genus Aepyornis, there were four species, A. gracilis, A. hildebrandti, A. maximus and A. medius. In the genus Mullerornis, there were three species, M. betsilei, M. agilis and M. rudis.
Originally, these birds lived all over the island of Madagascar. One theory states that the birds were hunted to extinction and their homes were destroyed. Since eggshell remains were found along with the remains from human fires, it is thought that humans took the eggs of the elephant birds and used them for food.
Another theory says that the birds died as a secondary effect of human impact resulting from the transfer of diseases from chickens and other birds.
- It is possible that these birds grew so large due to a phenomenon called island gigantism. Island gigantism is when the animals of an island grow drastically larger than their mainland relatives.