Humans aren't the only creatures that suffer from substance abuse problems. Horses eat hallucinogenic weeds, elephants get drunk on overripe fruit and big horn sheep love narcotic lichen. Monkeys' attraction to sugar-rich and ethanol-containing fruit, in fact, may explain our own attraction to alcohol, some researchers think.

Now, dolphins may join that list. Footage from a new BBC documentary series, "Spy in the Pod," reveals what appears to be dolphins getting high off of pufferfish. Pufferfish produce a potent defensive chemical, which they eject when threatened. In small enough doses, however, the toxin seems to induce "a trance-like state" in dolphins that come into contact with it, the Daily News reports:

The dolphins were filmed gently playing with the puffer, passing it between each other for 20 to 30 minutes at a time, unlike the fish they had caught as prey which were swiftly torn apart. Zoologist and series producer Rob Pilley said that it was the first time dolphins had been filmed behaving this way. At one point the dolphins are seen floating just underneath the water's surface, apparently mesmerised by their own reflections.

The dolphins' expert, deliberate handling of the terrorized puffer fish, Pilley told the Daily News, implies that this is not their first time at the hallucinogenic rodeo.

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