MASTODONS

Mastodons are extinct proboscideans that range from Miocene age (about 15 million years ago) to about 10,000 years ago. Mastodons belong to family Mammutidae. They preferred to live in woodland savannahs areas and browsed primarily on leaves and other foliage. Their earliest fossil record is in Africa, Asia, and Europe. They were, in fact, the dominant megamammals in the world during the mid Miocene, and at this time, they migrated into North America, most likely via the Beringia 2 land bridge (see one of my previous posts).

The earliest “relatives” of mastodons are 1) the Eocene anthracobunids (no tusks) from northeast Pakistan and northwest India, and 2) the Oligocene paleomastodons from Africa. Some reports of co-called “Mastodon” fossils are actually gomphotheres (see one of my previous posts). 

The term Miomastodon” (in the diagram above) is in quotes because some workers consider it to be a mastodon, whereas others consider it to be a gompothere. “Miomastodon” is found in the Miocene-age basal bone bed at Sharktooth Hill, southern central California. 

In contrast to the controversy surrounding MIomastodon, Mammut americium was definitely a mastodon. Its most widespread distribution was during the Pleistocene, with occurrences in Alaska, Ontario (Canada), New England, Florida, New Mexico, California, and Honduras in Central America.

Mammut americanum is especially well known from latest Pleistocene (about 10,000 years old) asphalt deposits at Ranch La Brea tar pits in Los Angeles County, southern California.  Well preserved specimens of this elephant-like mammal are 6 feet tall at the shoulder. They have long elephant-like trunks. Their teeth consist of low-rounded cusps separated by wide gaps. They fed on leaves and twigs rather than grass.

Three views are shown here of “Simi mastodon” Mammut americanum, late Pleistocene (50,000 yrs), Simi Valley, CA. This specimen is now on display at the “Age of Mammals Hall,” Natural History Museum of Los Angeles County, southern California.