Climate Change, Possible Dispersals, and Afrocentrism

From about the time of the first definitive tool use, the climate has started fluctuating more rapidly, ocillating on about a 40 thousand year cycle. This transisitons to higher intensity flutuations at about 1 million years ago. Many have suggested that the glacial-interglacial cycles are associated with early Homo erectus spreading to Eurasia because the Sahara Desert becomes savannah-like at some points during these fluctuations. Also, as our ancestors became more adept tool makers, many have speculated that they would have been able to master new environments. With so many fluctutations in paleoclimate, many have wondered about haw many migrations of hominids might have emerged from Africa and how complicated the interchange events might have been. The record of paleoclimate is more complete than fossil or artifact records, and it is much more difficult to see movements of our ancestors than it is to see changes in global ecology. One thing is consistent, however. From the advent of the first stone tool use all the way to the agricultural revolution, things invariably happen first in Africa and then spread to Eurasia. This phenomenon is regular enough that many have speculated that many waves of migration have emerged from Africa over the last 1.5 million years, each spreading across and affecting Eurasia is a slightly different manner.

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