17 Mart 2013 Pazar

Nebraska State Fossil

Nebraska State Fossil

Woolly Mammoth (common name)
Mammuthus primigenius 
(scientific name)

A woolly mammoth is an extinct species of mammal belonging to the same family as modern African and Asian elephants, although recent research shows that the mammoth is more closely related to the African elephant. The woolly mammoth and modern elephants also belong to the same order as mastodons. The woolly mammoth lived in Pleistocene North America, Asia, and Europe. It is believed to have lived at the end of the last ice age, about 10,000 years ago to possibly as long as 1.6 million years ago.
During the last major glaciation, called the Wisconsin glaciation, many species of cold-climate adapted mammals occupied the Bering Land Bridge and adjacent parts of Siberia-Chukotka, Alaska, and the Yukon, collectively called Beringia. Bison, caribou, woolly mammoths, and several different species of horses were the most abundant large mammals at that time. After entering North America on the land bridge about 65,000 years ago, woolly mammoths migrated as far south as what is now Kansas.
Although the best mammoth remains are usually found in the western part of Nebraska, frequently near major rivers, mammoth fossils have been found in all 93 of Nebraska’s counties. Three species of mammoth have been found in Nebraska: woolly, Columbian, and imperial mammoths. The most famous discovery in the state was a 15-ton, 14-foot specimen found in Lincoln County in 1922. This specimen is the world’s largest exhibited elephant skeleton. It resides at the University of Nebraska State Museum in Lincoln. The mammoth was designated the official fossil of the state of Nebraska on March 1, 1967, the 100th anniversary of the state.
In 1983, a woolly mammoth skeleton was found at Colorado Creek, Alaska. In 1986, the woolly mammoth became the official fossil of the state of Alaska.
German scientist Johann Friedrich Blumenback first described mammoths in 1799. He gave them the scientific name Elephas primigenius, but changed it to Mammuthus primigenius after discovering the woolly mammoth to be a distinct species. In addition to a thick layer of long hair, the woolly mammoth also had an undercoat of wool. This undercoat, as well as the animal’s size, gave it its common name
Only slightly larger than modern Asian elephants, full-grown mammoths reached heights of about nine to 13 feet (2.7 to 4.0 m) and weighed six to eight tons (5,450 to 7,300 kg). The woolly mammoth’s tusks weighed up to 200 pounds (91 kg) and measured over 12 feet (3.7 m) in length. Tusks, carried by both sexes, displayed status and fitness. As has been observed among modern elephants, woolly mammoths are also believed to have engaged in heated physical battles often leading to fatal injuries. 
The ice-age woolly mammoth, in contrast to its present-day African and Asian cousins, was strictly an herbivorous grazer. Mammoth tooth and bone fossils are frequently found in the midwestern United States. Mammoth teeth are composed of a set of cemented enamel plates, making them very resistant to wear. This property was essential for these vegetarians, as eating grass wears teeth quickly.
Looking very much like a short elephant with a shaggy coat of insulating hair, the woolly mammoth had droopy hindquarters. Its dome-shaped skull was topped with a tuft of hair. While its back end had a tiny hairy tail, its front end sported a hand-like trunk that was split at the tip. 
Scientists do not know definitively what killed the woolly mammoth. Theories as to what caused the great mammalian extinction at the end of the last ice age include climate change, overhunting by humans, a deadly virus, or perhaps some combination of these factors. The species died out about 10,000 years ago, around the same time that many other North American mammals became extinct.
Rather than actually fossilizing, most woolly mammoths were mummified. Many cases of mummified mammoth remains have been discovered in Alaska and Russia. Mammoth mummies form when a specimen becomes buried by sediment relatively quickly following its death. At the same time, a rise in the permafrost table has to take place, at which point the carcass would freeze while suspended in a more or less preserved state on account of the sediment. The result is mummification, which has allowed scientists to learn much about these ancient animals.
A reindeer breeder and hunter in Siberia discovered an almost perfectly preserved baby woolly mammoth in 2007. She was six months old at her death, which is believed to have been about 40,000 years ago. Named Lyuba, the mammoth is on exhibit at Chicago’s Field Museum from March to September 2010.
In the 2002 animated movie Ice Age, a saber-toothed tiger, a sloth, and a woolly mammoth find a lost human infant and try to return him to his tribe.
In 2008, scientists at Penn State University in University Park, Pennsylvania, sequenced the genome of the woolly mammoth. They were the first team to report the nuclear genome sequence of an extinct animal.

Click to enlarge an image
State Prehistoric Creature
Woolly Mammoth Dig Site
State Prehistoric Creature
Woolly Mammoth Skeleton
State Prehistoric Creature
Woolly Mammoth Reconstruction

Species:M. primigenius
Author: World Trade Press

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