Proboscidea is an order containing only one family of living animals, Elephantidae, the elephants, with three living species (African Bush Elephant, African Forest Elephant, and Asian Elephant).

During the period of the last ice age there were more, now extinct species, including the genus of elephants Mammuthus (mammoths) and the elephant-like species the mastodons. Further back in time, in the late Tertiary, there were many more different types, including the "shovel tuskers" like Platybelodon and Amebelodon. The earliest known proboscidean is Phosphatherium dating from paleocene deposits of Morocco. From the Eocene, several very primitive proboscideans are known, including the African Numidotherium, Barytherium, Moeritherium and the Anthracobunidae from the Indian subcontinent.

Origins

Paleontologists know of about 170 fossil species which they classify as belonging to the Proboscidea (Gr. proboskis, elephant's trunk, from pro, before, + boskein, to feed) group. The oldest dates from the early Tertiary period, over 56 million years ago. A discovery in December, 2003 has forced a new estimate of the age of elephant-like species to around 27 million years. Most of these early elephants had four short tusks; two on the upper jaw and two on the lower. Primelephas, the ancestor of mammoths and modern elephants, appeared in the late Miocene epoch, about 7 million years ago. The evolution of the elephant-like animals mainly concerned the proportions of the cranium and jaw and the shape of the tusks and molar teeth.

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