Interview: Michael Pollan

The best-selling author at the centre of a revolt against processed food shares some simple rules for truly healthy eating with Jon Henley

Mountain rescuers in distress

Ed Douglas: The rapid increase in inexperienced hill walkers is undermining the foundations of a British volunteer success story

Primary sources

John Crace rounds-up research news from around the globe, this week: the chimpanzees that have developed their own tool kits

In pursuit of the greatest happiness

Tim Worstall: GDP is not the be-all and end-all of our existence; it talks of value added to economies but has little to say about anything else