We think of medical science and doctors as focused on treating conditions--whether it's a cough or an aching back. But the sicknesses and complaints that cause us to seek medical attention actually have deeper origins than the superficial germs and behaviors we regularly fault. In fact, as Jeremy Taylor shows in Body by Darwin, we can trace the roots of many medical conditions through our evolutionary history, revealing what has made us susceptible to certain illnesses and ailments over time and how we can use that knowledge to help us treat or prevent problems in the future.

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