Joining the ranks of modern myth busters, Dr. Sharon Moalem turns our current understanding of illness on its head and challenges us to fundamentally change the way we think about our bodies, our health, and our relationship to just about every other living thing on earth, from plants and animals to insects and bacteria. So why does disease exist? Moalem proposes that most common ailments--diabetes, hemochromatosis, cystic fibrosis, sickle cell anemia--came into existence for very good reasons. At some point they helped our ancestors survive some grand challenge to their existence. Examining the evolution of man, Moalem reveals the role genetic and cultural differences have played in the health and well-being of various races, including their susceptibility to disease. With mesmerizing insight, Moalem offers groundbreaking insight into: - How diabetes may be a biproduct of a mechanism that helped humans survive the Ice Age- Why African Americans living in the north might suffer from vitamin D deficiencies, - Why Asians cant drink as much alcohol as Europ