N J Weller

Chiltern boards the 23:50 sleeper train from London to Edinburgh with two pork pies, six beers and a packet of chocolate digestives. At 23:55 he sends a message to all 158 people in his contacts, telling them that he plans to end his life in the morning. He then switches his phone to flight mode. He’s said goodbye. To him, it’s the end of his story - and time to crack open the biscuits. But across the world, 158 phones are lighting up with a notification.

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 might be a disease now, but is it really just a troublesome side-effect of our complex evolutionary past?

Where is the best place to find life beyond Earth? We often look to Mars as the most promising site in our solar system, but recent scientific missions have revealed that some of the most habitable real estate may actually lie farther away. Beneath the frozen crusts of several of the small, ice-covered moons of Jupiter and Saturn lurk vast oceans that may have been in existence for as long as Earth, and together may contain more than 50 times its total volume of liquid water. Could there be organisms living in their depths?