survival of the sickest

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.