Mammoth construction of the Great Pyramid of ancient Egypt. The earliest known proboscideans, the clade that contains the elephants, existed about 55 million years ago around the Tethys Sea area. The closest relatives of the Proboscidea are the sirenians and the hyraxes. The family Elephantidae is known to have existed six million years ago in Africa, and includes the living elephants and the mammoths. Among many now extinct clades, the mastodon is only a distant relative of the mammoths, and part of the separate Mammutidae family, which diverged 25 million years before the mammoths evolved. The following cladogram shows the placement
Manis Mastodon Site tests dated the Manis site at 13,800 years old. Since the 1950s, archaeologists have believed the Clovis people were the first human inhabitants of North America and that they lived here 13,000 years ago. However the discovery of sites pre-dating Clovis, such as Monte Verde in Chile and Meadowcroft Rockshelter in Pennsylvania, have been challenging this presumption at least since the 1990s. The Manis Mastodon Site is 800 years older than the Clovis people. This site, among others, is helping to change the long-held beliefs of many archaeologists about the earliest human inhabitants of North America. The Manis Mastodon Site