The American Mastodon (Mammut americanum), lived during the Pleistocene between 10 and 12 thousand years ago. This 11 foot cast, was created by Dr. Cliff Jeremiah. The mastodon was found in the Aucilla River near Tallahassee. He was discovered on a dive in 1968, and the underwater excavation took three years. Mastodons were smaller than wooly mammoths and their appearance was closer to that of modern elephants, their distant relatives.