We usually think of farmers as sturdy, Midwestern types who raise their ruddy-cheeked children on a balanced diet of eggs, potatoes, and chores. A study from researchers at Emory University, though, suggests that our farming ancestors weren't the picture of health. When humans transitioned from hunting and gathering to farming and living in cities, the authors say, they became malnourished and more prone to disease. Oh, and they were shorter.