Labradors are known for being greedy dogs, and now scientists have come up with a theory about the genetic factors that might be behind their behaviour. Science correspondent and flat-coated retriever owner Nicola Davis visits Cambridge University to meet Dr Eleanor Raffan and Prof Giles Yeo to find out how understanding this pathway could help us treat the obesity crisis in humans. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>