Prof. Wu Xiaohong, Director of China's National Lab of Quaternary Chronology, poses for photos in a radiocarbon lab of Peking University in Beijing Thursday, June 28, 2012. Wu and her archaeologist ... more 
Prof. Wu Xiaohong, Director of China's National Lab of Quaternary Chronology, poses for photos in a radiocarbon lab of Peking University in Beijing Thursday, June 28, 2012. Wu and her archaeologist team members have determined pottery fragments found in a south China cave to be 20,000 years old, making them the oldest known pottery in the world. (AP Photo/Alexander F. Yuan) less 
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Associated Press | Photo By Alexander F. Yuan
Thu, Jun 28, 2012 3:12 PM EDT