In this sweeping exploration of the relatively recent obesity epidemic, Michael L. Power and Jay Schulkin probe evolutionary biology, history, physiology, and medical science to uncover the causes of our growing girth. The unexpected answer? Our own evolutionary success.

For most of the past few million years, our evolutionary ancestors' survival depended on being able to consume as much as possible when food was available and to store the excess energy for periods when it was scarce. In the developed world today, high-calorie foods are readily obtainable, yet the propensity to store...

After drawing its first breath, every newborn mammal turns his or her complete attention to obtaining milk. This primal act was once thought to stem from a basic fact: milk provides the initial source of calories and nutrients for all mammalian young. But it turns out that milk is a much more complicated biochemical cocktail and provides benefits beyond nutrition. In this fascinating book, biologists Michael L. Power and Jay Schulkin reveal this liquid's evolutionary history and show how its ingredients have changed over many millions of years to become a potent elixir. Power and Schulkin...