Hoeveel klimaatveranderingen trotseerde de mensheid?
1995
Paepe R.
For the last 15 million years (Ma), Mankind has gone through at least five cycles of climate changes which were characterized by a range of extreme cold/dry and warm/humid climate variations between which there could be interference. Durig the first cycle from 15 Ma until 5 Ma, hominids such as Ramapithecus developed into perfect bipeds such as Australopithecus. During the second cycle from 5 Ma until 2,4 Ma, Australopithecus kept on diversifying. A general cooling due to the development of the Antarctic ice cap prevailed for both these cycles. The third cycle started with the glaciation of the northern hemisphere and the evolution of Australopithecus afarensis Lucy around 2.6-2.4 Ma, several branches of them developed between 2.0 Ma and 1.4 Ma. They vanished after suffering 35 climate changes of which three extremely long and cold periods around 2.4, 2.0 and 1.4 Ma successively. Then came Homo erectus who again went through about twenty climate changes including two extremely cold periods around 900 and 600 Ka (thousand years). He was finally followed by Homo sapiens neanderthalensis from 700 Ka who, while going through about ten climate changes, survived the cold periods of 600 and 200 Ka. Homo sapiens neanderthalensis reached the fourth cycle from 127 Ka until 10 Ka and faced 8 climate changes before being replaced from 45 Ka onwards by Homo sapiens sapiens who went through 5 climate changes again. The fifth cycle, our Present interglacial period, from the last 10 Ka until today, included 20 climate changes during which the cultural phases of the Mesolithic, the Neolithic, the Bronze Age and the least 100 known climate changes since Lucy (2.6 Ma). However, considering the interglacial and interstadial subcycles of the last 2.6 Ma, a total figure of 1500 climate changes does not seem excessive.
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