In Unfit for Purpose, biologist and broadcaster Adam Hart explores the mismatch between our fundamental biology and the modern world we have created. In each chapter Adam reveals the many ways in which biological adaptations that evolved to help us survive and thrive now work against us. For example, in the modern world stress is a killer but how did 'fight or flight' instincts turn from life-savers to life-takers? Obesity is a disease now but is it also just a side-effect of our evolutionary past? Whether it's the derailing of microbes in our gut, the rise of gluten and lactose intolerance, problems of social media or drug addiction, we always seem to have one foot in the modern world and the other firmly in our evolutionary past.