Fabulous book! The first half recounts the changes in human physiology, from the time we first diverged from apes (chimpanzees specifically) to modern times. Dr Lieberman discusses the physical adaptations and what they mean for the way our bodies function. Then he takes this history of the human body and shows us evolutionary mismatches between our physiology and our modern lifestyle, first starting with the foods we eat, and then discussing our bodies needs to be physically active, that we were born to run/walk long distances, and that our bodies suffer if we fail to be active. For example he notes that people that run barefoot, rarely suffer foot injuries, in contrast to runners that wear shoes (barefooters also hit with the ball of the foot first, unlike shod runners who strike with their heel). Type II Diabetes, Heart disease, and cancer are discussed in detail. I found it especially interesting how our bodies process different types of foods, how damaging starches and carbs are, compared to protein, fat, fiber, and how the composition of what you eat, affects whether it is sent for fat storage, whether it triggers insulin shock or absorbed slowly and more healthily.