Death is inevitable, we're told. Everything wears out, and that includes our bodies. So aging is a matter of wearing out. The conventional wisdom is that we get old - and eventually die - simply because our bodies become too worn to function as they should. But what if the conventional wisdom is completely wrong? There is growing evidence that senescence and death are inventions, evolutionary creations that serve a specific and previously unsuspected purpose. The evidence says that they are in fact weapons developed in the course of our struggle to defeat our parasites. The new view is that we die not because we "wear out," but to prevent parasites from overwhelming the human species. The same evidence explodes the conventional wisdom about sex. We recognize the act of sex as the way we conceive children. We accept sexual drive and attraction as potent forces shaping our personal identities and our relationships. But not many of us are aware that scientists have historically regarded sex as a true mystery. They have never been unable to fully account for the intricacies of sexual reproduction. In fact, emerging evidence shows that death and sex bear a close relationship to immunity. Our immune functions protect us from pathogens. As it turns out, death and sex perform a similar function. In this sense all these seemingly unrelated things can be grouped under the same grand umbrella. "Dead Sexy" is a fascinating read that traces the connection between immunity, death, and sex. It is a user-friendly book that weaves together a wealth of scientific findings to clearly explain how these weapons came to be, exactly how they protect us, and how better understanding them can improve our quality of life.