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The last glacial period, popularly known as the Ice Age, was the most recent glacial period within the Quaternary glaciation occurring during the last 100,000 years of the Pleistocene, from approximately 110,000 to 12,000 years ago.〔(【引用サイトリンク】title=Glaciation of Wisconsin )〕 Scientists consider this "ice age" to be merely the latest glaciation event in a much larger ice age, one that dates back over two million years and has seen multiple glaciations. During this period, there were several changes between glacier advance and retreat. The Last Glacial Maximum, the maximum extent of glaciation within the last glacial period, was approximately 22,000 years ago. While the general pattern of global cooling and glacier advance was similar, local differences in the development of glacier advance and retreat make it difficult to compare the details from continent to continent (see picture of ice core data below for differences). From the point of view of human archaeology, it falls in the Paleolithic and Mesolithic periods. When the glaciation event started, ''Homo sapiens'' was confined to Africa and used tools comparable to those used by Neanderthals in Europe and the Levant and by ''Homo erectus'' in Asia. Near the end of the event, ''Homo sapiens'' spread into Europe, Asia, and Australia. The retreat of the glaciers allowed groups of Asians to migrate to the Americas and populate them. ==Origin and definition== The last glacial period is sometimes colloquially referred to as the "last ice age", though this use is incorrect because an ice age is a longer period of cold temperature in which ice sheets cover large parts of the Earth, such as Antarctica. Glacials, on the other hand, refer to colder phases within an ice age that separate interglacials. Thus, the end of the last glacial period is not the end of the last ice age. The end of the last glacial period was about 10,500 BCE, while the end of the last ice age has not yet come. Over the past few million years the glacial-interglacial cycle has been "paced" by periodic variations in the Earth's orbit via Milankovitch cycles which are thus the "cause" of ice ages. The last glacial period is the best-known part of the current ice age, and has been intensively studied in North America, northern Eurasia, the Himalaya and other formerly glaciated regions around the world. The glaciations that occurred during this glacial period covered many areas, mainly in the Northern Hemisphere and to a lesser extent in the Southern Hemisphere. They have different names, historically developed and depending on their geographic distributions: Fraser (in the Pacific Cordillera of North America), Pinedale (in the Central Rocky Mountains), Wisconsinan or Wisconsin (in central North America), Devensian (in the British Isles), Midlandian (in Ireland), Würm (in the Alps), Mérida (in Venezuela), Weichselian or Vistulian (in Northern Europe and northern Central Europe), Valdai in Eastern Europe and Zyryanka in Siberia, Llanquihue in Chile, and Otira in New Zealand. The geochronological Late Pleistocene comprises the late glacial (Weichselian) and the immediately preceding penultimate interglacial (Eemian) preiond. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Last glacial period」の詳細全文を読む スポンサード リンク
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