Mastodons were large, proboscidean mammal species of the extinct genus Mammut that inhabited North and Central America during the late Miocene or late Pliocene up to their extinction at the end of the Pleistocene 11,000 years ago. The American mastodon is the most recent and best-known species of the genus.
While mastodons had a size and appearance similar to elephants and mammoths, they were not particularly closely related. Their teeth differ dramatically from those of members of the elephant family; they had blunt, conical, nipple-like projections on the crowns of their molars, which were more suited to chewing leaves than the high-crowned teeth mammoths used for grazing; the name mastodon (or mastodont) means “nipple teeth” and is also an obsolete name for their genus. Their skulls are larger and flatter than those of mammoths, while their skeleton is stockier and more robust.
The American mastodon (Mammut americanum), the most recent member of the genus, lived from about 3.7 million years ago until it became extinct about 10,000 years BCE. It is known from fossils found ranging from present-day Alaska and New England in the north, to Florida, southern California, and as far south as Honduras.
The American mastodon resembled a woolly mammoth in appearance, with a thick coat of shaggy hair. It had tusks that sometimes exceeded five meters in length; they curved upwards, but less dramatically than those of the woolly mammoth. Its main habitat was cold spruce woodlands, and it is believed to have browsed in herds.
They are generally reported as having disappeared from North America about 12,700 years ago, as part of a mass extinction of most of the Pleistocene megafauna, widely presumed to have been as a result of rapid climate change in North America, as well as the sophistication of stone tool weaponry used by the Clovis hunters. The latest Paleo-Indians entered the American continent and expanded to relatively large numbers 13,000 years ago, and their hunting may have caused a gradual attrition of the mastodon population.