This week will be the final fossil bird week to close out the year. I had contemplated discussing one of the oldest extant species of birds, the Magpie Goose (Anseranas semipalmata), but decided to be entirely fossil oriented to close out the bird topic. The fossil bird this week is the genus Aepyornis, a group of extinct ratites endemic to Madagascar. Known colloquially as Elephant Birds, the genus consisted of four species (A. gracilis Monnier 1913; A. hildebrandti Burckhardt 1893; A. maximus I. Geoffroy Saint-Hilaire 1851; and A. medius Milne-Edwards and Grandidier 1866) and is touted as the heaviest group of birds to have ever lived. The largest, A. maximus, is known to have weighed up to 400 kg (880 lbs). This is a known number because Elephant Birds have only been extinct for approximately 1000 years. Being a ratite, and weighing 400 kg, Aepyornis species were not capable of flight, no matter how much they may have wanted to escape Madagascar. Ratites tend to look vaguely like chicks throughout ontogeny, and such "youthful" appearances may have caused early explorers to assume that Aepyornis was not fully grown, even at 400 kilograms. However, use of the name Elephant Bird by many, including Marco Polo, may have actually referenced raptors living on or near Madagascar more than the giant ratites. Despite a confused nomenclature, Elephant Birds are enormous recently extinct ratites, like Moas, that went extinct partially because of human interaction (i.e. hunting). Considering an Aepyornis egg was large enough to feed a small family hunting the animals to extinction does not seem very far-fetched at all.
Left to right: Aepyornis maximus, Struthio camelus, Homo sapiens |
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