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Concept
Steppe à mammouths
Résumé
During the Last Glacial Maximum, the mammoth steppe, also known as steppe-tundra, was once the Earth's most extensive biome. It stretched east-to-west, from the Iberian Peninsula in the west of Europe, across Eurasia to North America, through Beringia (what is today Alaska) and Canada; from north-to-south, the steppe reached from the arctic islands southward to China. The mammoth steppe was cold and dry, and relatively featureless, though topography and geography varied considerably throughout. Some areas featured rivers which, through erosion, naturally created gorges, gulleys, or small glens. The continual glacial recession and advancement over millennia contributed more to the formation of larger valleys and different geographical features. Overall, however, the steppe is known to be flat and expansive grassland. The vegetation was dominated by palatable, high-productivity grasses, herbs and willow shrubs.
The animal biomass was dominated by species such as reindeer, muskox, saiga antelope, bison, horses, woolly rhinoceros and woolly mammoth. This ecosystem covered wide areas of the northern part of the globe, thrived for approximately 100,000 years without major changes, but then diminished to small regions around 12,000 years ago.
At the end of the 19th century, Alfred Nehring (1890) and Jan Czerski (Iwan Dementjewitsch Chersky, 1891) proposed that during the last glacial period a major part of northern Europe had been populated by large herbivores and that a steppe climate had prevailed there. In 1982, the scientist R. Dale Guthrie coined the term "mammoth steppe" for this paleoregion.
The last glacial period, commonly referred to as the 'Ice Age', spanned from 126,000 YBP–11,700 YBP and was the most recent glacial period within the current ice age which occurred during the last years of the Pleistocene epoch. This arctic environment was very cold and dry and probably dusty, resembling mountaintop environments (alpine tundra), and was very different from today's swampy tundra.
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