Octopuses and ecstasy

Sorry for the delay. Having the flu will suspend even the greatest blogs 😀

Today's article was recently featured on National Public Radio and even gained significant interest on social media platforms, what is all the hype about?

There is some irony here for two reasons. 1. Octopuses have the ability to rapidly change skin pigments creating lucid and trancey displays for camouflage or defensive behaviors. So I found it ironic that a creature capable of creating its own strobe show would be given ecstasy (MDMA), 2. The superficial and viral nature of stopping at, "octopuses were given ecstasy" downplays the importance of the findings presented by the authors. So here, we are going to dive a bit deeper into the importance of what the authors discovered.

To start, ecstasy is a psychomotor stimulant and has the potential to induce prosocial behavior in people and rodents. Notably, people and rodents are social and have centrally organized nervous systems. So the research question being asked here is twofold, 1). Can ecstasy increase social behavior in an organism that is not typically social and 2) Does ecstasy bind to the same 'spot' in octopuses as it does in humans and rodents?

First, the authors wanted to determine if the gene that encodes the serotonin transporter is present in the octopus and indeed it was, which provides the foundation that despite 500 million years of divergent evolutionary pressure the serotonin transporter could serve similar functions in vertebrates and invertebrates. This is important because just having the gene does not necessarily mean it codes the same functional protein. The authors tested if the conserved gene in octopuses encodes the same functional binding 'pocket' for the ecstasy that it does in other vertebrate species, and fascinatingly, it did. Then to fully test their hypotheses, they administered ecstasy to octopuses and measured social behaviors to another octopus and objects. When given ecstasy, the octopuses increase the amount of nonaggressive social contacts with another octopus, suggesting that the serotonin transporter has the ability to increase prosocial behavior. Awesome!

This is so powerful because the authors increased social behavior in a species that is normally asocial. Therefore, the binding pocket of the serotonin transporter is highly conserved across species and acts to functionally increase social behavior. Additionally, this new approach here opens many avenues for understanding molecular pharmacology and evolutionary determinants of behavior.

The original article by Eric Edsinger and Gül Dölen, "A conserved role for serotonergic neurotransmission in mediating social behavior in octopus" was featured in the journal, Current Biology.