When we’re confronted with new information, we instinctively question whether it comes from a reliable source – and that thirst for evidence stretches through most areas of our lives. If we look at science – biology, geology, chemistry – nothing is possible without evidence – you can’t prove or disprove a hypothesis, you can’t move forward or come to conclusions.

On today’s show, we’ll take a look at different kinds of evidence – how we use it, and how we know it’s solid. We’ll meet a biologist who’s borrowing some moves from forensic science, we’ll sit down with a hypnotist trying to crack cold cases, and find out how people in the Arctic knew they were on thin ice.