Scientific American: In the rolling foothills of the madison range in southwestern Montana, a cabin-style house sits beside a washboard dirt road. A few horses loiter in a corral outside, and spotted ranch dogs bark and jump at the fence. James Stuart, manager of Sun Ranch, lives here with his wife and three kids. Christian, the oldest at four years, just got his first pony. Stuart, who comes from a long line of rugged Scots who settled this region, has auburn hair and eyes lined from squinting–or …