Their hunting caused a gradual attrition of the mastodon and mammoth populations, significant enough that over time the mastodons may have been hunted to extinction. However, it is not considered plausible that the disease could have caused the extinction on its own.Īnother factor contributing to their eventual extinction in America during the late Pleistocene may have been the presence of Paleo-Indians, who entered the American continent in relatively large numbers 13,000 years ago. Recent studies indicate that tuberculosis was common in late Pleistocene American mastodons, and it has been suggested that this could have contributed to their extinction 10,000 years ago. However more recent radiocarbon dates have been found, such as 5200 BCE in Seneca, Michigan, 5140 BCE in Utah, 4150 BCE in Washtenaw, Michigan, 4080 BCE in Lapeer, Michigan. Mammut americanum is generally reported as having disappeared from North America about 10,000 years ago, as part of a mass extinction of the Pleistocene megafauna. Mastodon fossils have been found on the Olympic Peninsula of Washington, USA (Manis Mastodon Site), in Kentucky (particularly noteworthy are early finds in what is now Big Bone Lick State Park) the floodplain of the East Branch of the DuPage River, near Glen Ellyn, Illinois the Kimmswick Bone Bed in Missouri in Stewiacke, Nova Scotia, Canada at a number of sites in New York State in Richland County, Wisconsin (Boaz mastodon) La Grange, Texas Southern Louisiana north of Fort Wayne, Indiana Savannah, Georgia and Johnstown, Ohio USA. Their remains have been found as far as 300 kilometers offshore of the northeastern United States, in areas that were dry land during the low sea level stand of the last ice age. Though their habitat spanned a large territory, American mastodons were most common in the ice age spruce forests of the eastern United States, as well as in warmer lowland environments. The regularity of the damage in the growth patterns of the tusks indicates that this was an annual occurrence, probably occurring during the spring and early summer. The curved shape of the tusks would have forced them downward with each blow, causing damage to the newly forming ivory at the base of the tusk. It is theorized that the damage was caused when the males were fighting over mating rights. Microscopic examination showed damage to the dentin under the pits.
MASTODONTE MAMUT SERIES
Examination of fossilized tusks revealed a series of regularly spaced shallow pits on the underside of the tusks.
The tusks were probably used to break branches and twigs, although some evidence suggests males may have used them in mating challenges one tusk is often shorter than the other, suggesting that, like humans and modern elephants, mastodons may have had laterality. However, it has been proven that female mastodons had lower pairs of tusks. Young males had vestigial lower tusks that were lost in adulthood. The tusks of the American mastodon sometimes exceeded five meters in length they curved upwards, but less dramatically than those of the woolly mammoth. Their skulls are larger and flatter than those of mammoths, while their skeleton is stockier and more robust. Mastodons' 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. However, there are number of significant skeletal differences between mastodons and mammoths. It was about 3 metres (9.8 ft) in height at the shoulder, also similar to woolly mammoths. A few skeletons have been found with the fur still attached examination of the hair suggests that mastodons lacked the undercoat characteristic of mammoths. The American mastodon resembled a woolly mammoth ( Mammuthus primigenius) in appearance, with a thick coat of shaggy hair. Its main habitat was cold spruce woodlands, and it is believed to have browsed in herds. 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. It was the last surviving member of the mastodon family. The American mastodon ( Mammut americanum) is an extinct North American proboscidean that lived from about 3.7 million years ago until about 10,000 years B.C.
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