http://www.philly.com/inquirer/magazine/20090831_Studying_ancient_man_to_learn_to_prevent_disease.html今天的费城询问报登了一篇文章说根据对南美的调查，说明人类一从事定居农业后，疾病就多了。打猎很长寿。
along the Georgia coast, the Pacific Northwest, and coastal Brazil, people grew tall and strong and lived relatively free of disease. They ate game, fish, shellfish, and wild plants.
But as corn farming spread through various regions of the Americas, people got shorter. Many became prone to anemia and began dying of tuberculosis and other infectious diseases
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