Dr Chris Smith and the Naked Scientist team present the latest science news, analysis and breakthroughs, In this week's episode...a huge outbreak of dengue fever in Brazil so should we be worried here in Europe? Also scientists discover the types of microbe that drive the decomposition of animal flesh and they do it in a pretty gruesome way. And where do we get our sense of humour from? Plus we find out how fish skin is fighting infection on the battlefield and take a look at the origins of medics in conflicts. Get the podcast from the BBC Sounds app.