Ma Yuanjiang survived eight days trapped under the rubble of an earthquake in China. He had no food or water, so he ate paper and drank his own urine. Ma had no training in survival. He was a business executive, yet somehow, against all odds, he survived longer than almost anyone else who has ever been trapped. How could this be? Movies and books often depict survivors as tough, confident guys, who know everything. But what about in real life? Who is most likely to survive a disaster?