Young dolphins were seen carefully manipulating a certain kind of puffer fish which, if provoked, releases a nerve toxin.
Though large doses of the toxin can be deadly, in small amounts it is known to produce a narcotic effect, and the dolphins appeared to have worked out how to make the fish release just the right amount.
Carefully chewing on the puffer and passing it between one another, the marine mammals then enter what seems to be a trance-like state.
After chewing the puffer gently and passing it round, they began acting most peculiarly, hanging around with their noses at the surface as if fascinated by their own reflection.