How did humans spend the ice age?

With human activities, humans can move south and live in areas where glaciers have not reached. In the long geological history, the earth has experienced three periods of continuous temperature decline, which geographers call "ice age". Among them, the Precambrian and Paleozoic ice ages lasted for tens of millions of years, while the Cenozoic ice age lasted for two million years. There is still no definite theory about the origin of the ice age. Some scholars believe that it may be related to the change of the periodic inclination of the earth's axis when the earth rotates, which leads to the decrease of sunlight exposure. The occurrence of the ice age is still a mystery of natural science. Although scientists have been quite sure that the changes of the earth's orbit around the sun and its rotation axis are closely related to the occurrence of the ice age, these changes will not change the incident energy of the sun, but only change the distribution of the incident sunlight, which can cause great changes in the climate on the earth, which makes scientists very confused. About two million years ago, the third ice age "Quaternary Ice Age" in geological history began at the same time, and the global temperature began to drop. Europe, North America and Greenland in the mid-latitude region of the northern hemisphere are all covered by large ice sheets extending all the way from the North Pole. During this period, there were five ice ages in Europe and four ice ages in North America and Chinese mainland. As for Taiwan Province Province, only the glaciers of the last ice age have been confirmed, that is, the late Pleistocene from 70,000 to 1 10,000 years ago. Scholars call it the "Snow Mountain Ice Age". The rising temperature of the North and South Poles caused the melting of the polar ice sheets. We should know that the melting of ice is endothermic, so the rise of the temperature at the two poles will correspondingly cause the global temperature imbalance, that is, the temperature drop. The last ice age was more than 50,000 years ago, because the climate of the earth was very sultry at that time, land animals adapted to the perennial high temperature of more than 40 degrees, and finally the global temperature dropped due to the temperature imbalance between the two poles, but the decline was not obvious. However, for many warm-blooded animals, even if the living environment temperature drops 10 degrees, it is fatal. By the way, human ancestors spent that period 50,000 years ago because they knew how to use the most basic warm-keeping measures. /question/7832586.html The study of Quaternary glaciers in China began with the famous geologist Li Siguang. 192 1 year, Li Siguang discovered glacier boulders in Datong, Shanxi Province and the eastern foot of Taihang Mountain in Hebei Province, and identified the scratches formed by glacier flow. In the 1930s, he discovered glacial sediments in Lushan Mountain, Jiangxi Province, and sheepback stones with glacial scratches in Poyang Lake. Scratches on the U-shaped valley wall were found in Huangshan Mountain, Anhui Province, and pebbles with scratches were found in the sea behind the mountain. After these important discoveries, Li Siguang published papers such as Quaternary Glacier in the Yangtze River Basin and Quaternary Glacier Phenomenon in Huangshan Mountain, Anhui Province, and later published a monograph Lushan Mountain in the Ice Age. He proposed that Lushan Glacier can be divided into three glacial periods, the oldest being "Poyang Lake Glacier", which occurred in the early Pleistocene and was the largest, and the green gravel beside Poyang Lake was important evidence. Then came the "Dagu Ice Age", which belonged to the early Middle Pleistocene, represented by the ochre mud and gravel in Dagushan area. The relatively new one is the "Lushan Ice Age", which belongs to the late Middle Pleistocene, and its scale has been greatly reduced. After the founding of the People's Republic of China, some scholars suggested that the "Dali Ice Age" was later than the "Lushan Ice Age" and belonged to the late Pleistocene, represented by the moraine in Cangshan, Dali, Yunnan. In this way, the Quaternary has the above four glacial periods, which correspond to the four classical glacial periods proposed by German punk and brukner at the beginning of the 20th century based on the study of Quaternary glacial deposits in Alps. Li Siguang's theory about Quaternary Glaciers in eastern China had collaborators and supporters in the early days, including a group of China geologists such as Li Jie, and foreign geologists, such as Fessman in Austria, Narifkin in the former Soviet Union and Miller in the United States. The existence of Quaternary glaciers in China has attracted the attention of international geologists. Shi Yafeng, the pioneer of modern glacier research in China, questioned the existence of Quaternary glaciers in the middle and low mountainous areas in eastern China in the early 1980s. They believe that the so-called "ice bucket" in Lushan area does not have ice sill and ice bucket chassis topography, but is the result of simultaneous action of hillside block movement and flowing water erosion: "U-shaped valley" is a wide valley formed by flowing water acting on syncline valley or controlled by weak stratum; "Mud gravel" is the accumulation of gravity, ice-melting mud flow and ancient mud flow. They further concluded that the Quaternary temperature, snow line and area ratio of glacier accumulation area (AAR) in the middle and low mountainous areas in eastern China (below 3000m above sea level) were not suitable for glacier development. Whether there are glaciers in the Quaternary in eastern China has become an unsolved case. At present, this academic debate continues. But in the west of China, there is no doubt about the existence of Quaternary glaciers. As early as the early 1940s, when the famous geologist Huang led the petroleum geological survey in Xinjiang, he studied the Quaternary glacial sediments at the southern foot of Tianshan Mountain, published two papers, expounded the evidence of the existence of ice ages, and divided them into three ice ages, represented by different moraines. The above-mentioned moraine series can still be found in today's investigation, and it has been fully recognized in the whole academic community. The appearance of glaciers has a great influence on the global climate and biological development, especially the Quaternary glaciers, which directly affect the living environment of human beings. The study and confirmation of Quaternary glaciers has both special theoretical significance and universal practical significance, so it has always attracted people to make unremitting efforts. When the glacier came, not all continents were covered with ice and snow. There are no glaciers in many places because of the barrier of mountains and the difference of topography. Humans can live in these places or migrate to the warm south. The ice age was just cold, and there was no ice and snow all year round. In summer, glaciers will retreat and come back in winter.