Simultaneous Stone Age tool use: signs of early hand-ax making not limited to eastern Africa.
Ryan Gibbon of the University of Witwatersrand in Johannesburg and his colleagues dated hand axes and related stone implements, collectively known as Acheulean artifacts, using measures of the relative decay of radioactive forms of aluminum and beryllium in quartz from the soil and gravel bearing the artifacts. The team identified 465 tools brought out of a diamond-mining pit bordering South Africa's Vaal River, near the town of Windsorton. Those implements included 10 hand axes, two hand axes with large chopping edges known as cleavers and two elongated, three-sided picks.
The findings at Windsorton, published online December 20 in the Journal of Human Evolution, raise the question of whether human ancestors developed Acheulean tools independently in southern and eastern Africa at around the same time or developed the tools in only one area from which the tradition spread rapidly to distant regions.
The team's findings support a preliminary age estimate of 1.6 million years reported by other researchers for Acheulean artifacts from South Africa's Wonderwerk Cave, located about 100 kilometers northwest of Windsorton.
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|Article Type:||Brief article|
|Date:||Jan 31, 2009|
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