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History, Evolution, and The Darwin Debate

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Early man in Africa

June 29th, 2009 · 1 Comment

Human History Written in Stone and Blood

Two bursts of human innovation in southern Africa during the Middle Stone Age may be linked to population growth and early migration off the continent

This is an interesting article on the double series innovative periods in the emergence of modern man.
Note that natural selection is hardly mentioned, since this isn’t a question of slow evolution.
Despite pro forma attempts to produce hypotheses that can explain all this the clear tone is a veiled agnosticism (as it should be).

Catalysts of Creativity
Answers about the ages of these artifacts, of course, lead only to more questions. What stimulated the Still Bay and Howieson’s Poort industries? Why did they last so briefly and end so abruptly? And what was responsible for their—in archaeological terms—instantaneous appearance and subsequent disappearance across a vast expanse of southern Africa? Human responses to environmental change have long intrigued archaeologists, so climate change must top the list of suspects. The last interglacial/glacial cycle stretched from about 130,000 to 12,000 years ago, which includes the time span of the Still Bay and Howieson’s Poort. During this period, southern Africa experienced marked changes in temperature and precipitation associated with global changes in ice volume, sea level and patterns of oceanic and atmospheric circulation. The timing and magnitude of these climatic fluctuations have been detected by international climate research groups in the pattern of change in the ratio of oxygen isotopes (and the concentration of atmospheric greenhouse gases) in ice cores retrieved from Greenland and Antarctica. These records share many general features, but the Southern Hemisphere climatic records from Antarctica are the most relevant to southern Africa.

Tags: Evolution

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