This delights me. From the Beeb: Wild dolphins tail-walk on water.

A wild dolphin is apparently teaching other members of her group to walk on their tails, a behaviour usually seen only after training in captivity.

The tail-walking group lives along the south Australian coast near Adelaide.

One of them spent a short time after illness in a dolphinarium 20 years ago and may have picked up the trick there.

Scientists studying the group say tail-walk tuition has not been seen before, and suggest the habit may emerge as a form of "culture" among this group. [continue]