Researchers analyzed thousands of skeletons to get a general idea of the health of pre-Columbus Americans. They learned that in general they were fairly healthy 1,000 years before Columbus, but health was on a slow decline since then (interesting that EUrope was going through plagues and such in the Medevial ages while the American’s health was declining). Societies that relied on farming were generally less healthy, and the navites along the Brazilian coast most healthy (plains INdisans were also healthy). Urban envinronments appeared in America 2000 years ago, and agriculture 7000 years ago. And like with the Middle East, the appearance of these things match a decline in health. Also, in the Mayan culture, which had more urban and agriculture, people were less healthy.