Despite inhabiting a very different world to ourselves, dolphins perform brilliantly in our 'intelligence tests'. There is still much to learn about these flexible problem-solvers, but from the evidence so far, it seems that dolphins do indeed deserve their reputation for being highly intelligent. 

Up to now, many scientists have concentrated on the cultural transmission of behaviour from mother to offspring, but new research by Stan Kuczaj and his team have revealed some surprising results. They have noticed that, during play, calves are more likely to copy and learn from dolphins closer to their own age group.

via bbc.co.uk