Forged by natural selection and honed by evolution, humans are perfectly adapted machines. . . for a world that no longer exists.

In Unfit for Purpose, biologist and broadcaster Professor Adam Hart explores the mismatch between our fundamental biology and the modern world we have created. In each chapter, Adam explores how many biological adaptations that evolved to help us survive and thrive in a very different world are now working against us. For example, humans are superbly adapted famine survivors. Obesity might be a disease in the modern world, but it's really just a troublesome side-effect of some effective evolutionary brilliance. And in today's society, one of the biggest killers is stress. What started out as a life-saving fight or flight response in the face of bear attack might now cause headaches, loss of sex drive, depression and heart problems as we panic about missing deadlines or making sense of our work-life balance. And deep evolutionary relationships with microbes built up through an outdoor life have rapidly derailed leading to all kinds of gut and other auto-immune problems.

Throughout the book, Adam meets the scientists unraveling early human and primate evolution, the archaeologists exploring the very early stages of human society, and the clinicians and sociologists studying modern day diseases and conditions. In a world of our making, we find ourselves unfit for purpose. But all is not lost--by unpicking the evolutionary causes underpinning many of our current woes, Adam finds and tests an array of evolutionarily-informed treatments, from the straightforward to the downright weird.