It was heavier than "Aepyornis" and taller than the moa. The tibiotarsus is extremely large in comparison to "Aepyornis" and "Mullerornis". "Mullerornis" is smaller than the more well-known "Aepyornis". The pore arrangement and structure of "Incognitoolithus" is similar to that of "Aepyornis". Elephant birds comprised the genera "Mullerornis", "Vorombe" and "Aepyornis". It was heavier than the moa and taller than "Aepyornis", though slightly smaller than "Vorombe". The Melbourne Museum has two "Aepyornis" eggs. It is widely believed that the extinction of "Aepyornis" was a result of human activity. It is widely believed that the extinction of "Aepyornis" was the result of human activity. "Vorombe titan" was first described by Charles William Andrews as "Aepyornis titan" in 1894. They also recognized "Aepyornis ingens" as a synonym of "Vorombe titan". A second, side-blown "Aepyornis" egg was acquired at a later date. "Aepyornis maximus", the "elephant bird" of Madagascar, was the heaviest bird ever known.