锟斤拷学锟揭测定锟斤拷锟斤拷锟斤拷锟斤拷为锟斤拷锟斤拷锟角憋拷锟斤拷锟斤拷锟斤拷锟斤拷锟�“农锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷”锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟饺伙拷锟斤拷锟捷碉拷Bruce Smith 锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷凇锟斤拷锟斤拷锟斤拷锟窖г涸猴拷锟斤拷锟斤拷锟�
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锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷学院院锟斤拷锟斤拷锟斤拷
PNAS锟斤拷锟斤拷doi: 10.1073/pnas.0901846106 锟斤拷Bruce D. Smith锟斤拷Richard A. Yarnell锟斤拷
