Some researchers have doubts that mammoths lived in the cold climate zones. Recently, Russian scientists have received strong evidence of woolly mammoths' frost-resistance - they possessed sebaceous glands. The trip to visit mammoths was paid by the International Scientific and Technical Center, and the researchers' search for sebaceous glands was supported by the Federal Target Scientific and Technical Program entitled "Investigations and Developments for Science and Engineering Priority Guidelines in 2002-2006".
Specialists of the VECTOR State Research Center for Virology and Biotechnology and the Zoological Institute (Russian Academy of Sciences) have discovered sebaceous glands in the skin of woolly mammoths, the scientific community unsuccessfully looking for sebaceous glands for more than a hundred years. As sebaceous glands are an instrument of adaptation to cold climate, the discovery by Russian scientists serves a convincing argument in the dispute whether the mammoths did live in the frost.
The doubting researchers claim that we can restore appearance of zoolites, but not the conditions they used to live in. According to some data, the ice age climate was much warmer then it is believed, and therefore, the mammoths probably did not have to endure long ice-cold winters. However, questions arise not only about the climate of Beringia, but also about the mammoth's constitution. Although its appearance is habitual to us, many physiological peculiarities of this fur mountain with tusks are hard to reconstruct. For example, researchers failed to find mammoth's cutaneous, sudoriferous and sebaceous glands. The hair was known to be present, but sebaceous glands accompanying it were not in place. However, the elephant, mammoth's alive next-of-kin, does not possess them. Nevertheless, mammoths used to live in other latitudes and they are somehow entitled to differ anatomically from elephants.
It is known that sebaceous glands are well preserved in permafrost, they were found in the skin of the fossil bison. Unfortunately, there are few mammoths' remains suitable for detailed investigation. Starting from 1892, researchers have carefully investigated every new discovery, but no trace of sebaceous glands was found. However, in late 1980s, the Magadan scientists announced the finding of sebaceous glands in the skin of mammoth's leg, but they did not publish scientific description of their discovery. It turned out that mammoths had walked about with absolutely dry hair and skin, which does not accord with the appearance of the animal that spent major part of life in the snow-covered steppe.
In 2002, the Novosibirsk and St. Petersburg scientists expedition set off for Yakutia, in the region of the Muksunuoka River. The scientists extracted from the frozen ground the hand of the woolly mammoth's foreleg and the foot of the hind leg. A piece of skin about 6 centimeters thick was taken for investigation. It has turned out very difficult to prepare specimens for microexamination from the sample that spent several thousand years in permafrost. Having coped with this task, the researchers saw that the skin retained its texture in general. In the deep layer of derma that consisted of strong collagen fiber bundles, there were hair follicles and the hair itself, small blood vessels, and sudoriferous and sebaceous glands. The glands and their ducts are clearly seen on the slices. The scientists managed to make pictures of glands, produced their detailed description and have recently published a research article. Now the presence of sebaceous glands with wooly mammoths can be considered documentary proof. Therefore, these animals were pretty well protected from cold and could survive in the deep-frozen, blown-through steppe.
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