Woolly mammoth

The woolly mammoth ( Mammuthus primigenius ) is extinct Éléphantidé S and one of the representatives of the Mammuthus . Appeared there are 200 to 300.000 years, it occupied all the Eurasia, of the Iberian peninsula and the Scotland until in Siberia and even the North America which it reached by the Bering Strait, exondé during the Glaciation S. He was described scientifically for the first time in 1799 by Johann Friedrich Blumenbach, naturalist and anatomist of Göttingen, under the name of Elephas primigenius starting from made discoveries with Osterode.

Appearance

The species owes its name with its coarse fur of winter, made up of the hairs which can reach 90 centimetres. As for the Musk ox, this fur formed an apron on the belly and the sides. These hairs of cover covered a dense under-wool and a layer of grease of almost 10 centimetres, insulation which got a supplement of heat to him. The fur of summer was definitely shorter and less dense than the fur of winter.

Corpses of Mammouth S found in the ice often present a fur of reddish and relatively clear color, undoubtedly because of discoloration. The live animals had rather a color going from brown dark to the black. The adaptation to the cold climate of its habitat was marked by its very small ears and a short horn compared to current elephants. Their size was not so gigantic that it is believed. The adult males reached 2,80 to 3,40 meters with the garrot. The weight of such an animal could rise up to six tons. The woolly mammoth was as tall as a Indian elephant and a little smaller as a African elephant. The last representatives of the kind were usually smaller than the older mammoths which, by their size, still somewhat recalled the powerful mammoth of the steppes ( Mammuthus trogontherii ) from which they resulted. A dwarf form, probably Holocene, of woolly mammoth was described in the Wrangel island in Siberia. They reached nothing any more but 1,80 m height to the garrot. However, the woolly mammoth was the largest animal of the grassy Steppe at the glacial era. The differences striking with the kinds of elephants living today are the defenses very bent, a bump in the shape of cupola on cranium, a high bump on the shoulder as well as a falling croup. The defenses found until now reach 4,20 meters length for a weight going up to 84 kg. However, on average, they are only 2,5 meters long and weigh only 45 kilos. Another characteristic for this species is also the great number of plates on the molars.

Surface of distribution

The woolly mammoth spread itself at the glacial era in Eurasia and North America. At the coldest times, it is advanced as far as Central Europe, in China and on the current territory of the United States while being withdrawn regularly towards the North-East during the interglacial phases. The southernmost discoveries concerning this species were made in Europe, Spain and, in America, to Mexico. In the Far East, it reached Huang He in China.

Lifestyle

The preferred habitat of the woolly mammoth was the grassy steppe, a landscape where plants of steppes and plants of Toundra mixed. The examination of corpses of mammoths preserved in the ice showed that the woolly mammoths nourished mainly grass like, to a lesser extent, of branches of Saule S and of Mélèze S. In the stomach of the mammoth of Indigirka, one found branches of pines beside grasses. The presence of the woody plants in its food indicates that these animals were not only animals of steppes, but which they also advanced in forest ground. An animal alone was to introduce daily up to 180 kg of food (200 to 300 kg for a large adult male) and was probably occupied most of the day being sought some.

The woolly mammoths probably lived like the current elephants, i.e. in groups based on the matriarchy. The oldest female directed the group, normally made up from two to nine individuals. The adult males on the contrary carried out a solitary life and joined the females only during the rut.

Mammoths preserved in the ice

It is in Siberia, Alaska and in Canada, which one found best preserved the woolly mammoths in the ice. One of the best specimens was a young individual found close to Fairbanks, in Alaska. Only the head, the forefeet and the shoulders of the animal were preserved, but in particular the skin and the muscles were in excellent state. The analyzes of DNA which this discovery allowed were an essential contribution to establish the history of the evolution of this animal specie.

In 1799 mammoth of Adam celebrates it whom one admires today with the zoological museum of the Academy of Science of Saint-Pétersbourg was found in the delta of Lena. In 1864, on the Indigirka river in Siberia a well preserved corpse was discovered; it still carried remainders of fur and made it possible to know the contents of its stomach. In 1900, one found on the Kolyma river the mammoth known as of Beresowka, also preserved in the ice. A mammoth frozen in the ice was discovered in 1977 on the Juribei river in Siberia. It was approximately 10.000 years old.

Many of other corpses were found until today in the Siberian Pergélisol and in Alaska, where were the majority of the mammoths which lived there until approximately 40.000 years before the present. Some were so well preserved that scientists cherish the idea of being able the “ressusciter” by the methods of genetic technique. It is in particular the case of the babies mammoth “Dima” (found in a gold mine of the district of Magadan) and “Mascha” (coming from the gulf of Ob) which raised great hopes. But, until now, all these attempts failed, primarily because the DNA of the mammoths is too fragmented.

Dogs and wolves would have eaten meat of cold mammoths without harmful effects. On the other hand, it seems that the meat consumption of mammoths frozen by modern researchers or explorers is not veracious.

Extinction

The species disappeared at the end from the Pléistocène with a whole series from other large mammals. In Europe, it disappeared a little earlier than in Siberia and North America. On the continent, it seems to have disappeared approximately 10.000 years before Jesus-Christ.

A relictuelle population still lived in the island of Wrangel in Siberia approximately 4.000 years ago, i.e. at the time of the Egyptian Pharaons. As the traces of human presence in this island go up also at that time, one put forth the assumption according to which the man would have exterminated these animals in their making a too intense hunting. In the same way, in North America and Siberia, the disappearance of the mammoths coincides exactly with the first appearance of the men. The extinction of the mammoths must have had in each case a similar cause, it coincides besides with that of many of other large mammals at the end of Pleistocene. In addition to the assumption of surchasse, one also thinks of climate changes, and the question is not yet distinct. Most probable is that the two factors acted together. However the mammoth and much of other mammals of the glacial era had already survived strong fluctuations of climate, and influences it men was not at the time unimportant. Recently there is advanced the assumption of a supervirus to explain this wave of disappearance.

References

Claude Guerin, “Superordre of Proboscidiens”, in the large mammals plio-pleistocenes of Europe , Masson, coll “Prehistory”, Paris, 1996.

Note

Random links: