Octopuses are loners, but when they are drugged with MDMA (“ecstasy”), they are drawn to reach out to one another. This is the finding of a research project at Johns Hopkins.
The strange thing about this is that the organization of the octopus brain is so different from the human brain that it is quite surprising we would share any neurotransmitters or any biochemical targets of the small molecule MDMA. Octopuses are playful, they plan and remember, they strategize, they use tools—all these mental feats that until a few years ago were thought to belong uniquely to humans. But they evolved all these behaviors and abilities quite separately from vertebrates and mammals and primates and humans. Octopuses evolved directly from shellfish like the clam that have no real brain but only a cluster of nerves called a ganglion. If they evolved the same neurotransmitters we did, this is a mysterious case of convergent evolution. The many cases of convergent evolution that have been studied all involved a common function, not a common mechanism. For example, birds and bats and fruitflies all evolved wings independently, because wings are useful for flying. But neurotransmitters are thought to be arbitrary signal molecules which acquire a meaning according to the way they are interpreted. It is as though we had ET visitors from another galaxy, and found to our surprise that the language they spoke sounded a lot like Hungarian.
The octopuses given MDMA were moved to seek out cage containing another octopus, and to hug the cage because they weren’t permitted to make contact. Perhaps if the researchers had taken MDMA themselves, they would have had sufficient empathy to realize that they were being cruel to the octopuses.