Dolphins are thought of as one of the most intelligent species in the animal kingdom - and experts believe they have put their ingenuity to use in the pursuit of getting "high".
In extraordinary scenes filmed for a new documentary, 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.
The behaviour was captured on camera by the makers of Dolphins: Spy in the Pod, a series produced for BBC One by the award-winning wildlife documentary producer John Downer.