African and Indian Elephants are the only proboscideans (Order
Proboscidea) alive today, but there is a vast number of different
species in the order that are now extinct. There are also many cases of
parallel and convergent evolution. The closest living relatives of the
modern-day elephant are in fact the dassie, or hyrax, and sea cows:
manatees and dugongs. Sea cows and dassies are thought to have evolved
from a common ancestor to the Proboscidae.
The earliest known ancestors to the elephant were
herbivores that lived about 40 million years ago, and were roughly the
sizes of pigs and cows. The direct ancestor to the modern-day elephant
is unknown, but fossils of numerous evolutionary off-shoots, such as the
moerithenes (40 million years ago), the barythenes (40 to 35 million
years ago), paleomastodons (40 million years ago), gomphotheres such as
the mastodon, the stegodon, and the mammoth have all been found and
studied.
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