I grew up on a farm in land-locked Alberta. Apart from a couple of family vacations, the most experience I had with the ocean was watching fields of wheat break into waves on a correctly windy day. I have always been a bit hesitant when it comes to the Great Blue Sea. Its vastness and wide variety of occupants intimidate me. However, Vancouver’s close proximity to the Pacific has altered my mindset. Knowledge is power, and if I am able to understand bits of the ocean’s makeup, I will be less wary.
Link to Video of a Wheat Field in the Wind on Youtube
Researchers have published a paper which links humans and octopi through a common gene involved in social interaction that has been preserved independently in each lineage for over 500 million years. Their approach? A little trippy.
Chemical Structure of MDMA. Image courtesy of Erin Finnerty
Scientists from John Hopkins University and Josephine Bay Paul Center gave Octopus bimaculoides MDMA, the party drug also known as ecstasy, in an attempt to see its effects on social interaction. It is known that MDMA encourages prosocial behaviour in humans and mice, but invertebrates were never considered. Induced O. bimaculoides spend a significantly increased amount of time socially interacting with other octopi than when sober.
Chemical Structure of MDMA. Image courtesy of Erin FinnertyOctopuses were given the option to interact with an inanimate object, a social object (male or female octopus), or stay in the empty central area of a three-chambered tank. Untreated O. bimaculoides spend more time with the novel object than in the other tanks. When the social object is a female, subjects spend a larger amount of time in the social chamber than when the social object is a male. This shows a significant preference for female interaction.
These creatures are asocial and solitary, naturally interacting with others only for ecologically favourable purposes such as mating. MDMA increases serotonin levels in the body. Serotonin helps promote social interaction and therefore, positively influences sociality.
When soaked in an MDMA bath, O. bimaculoides prefers to spend time with male social objects than with the novel object. Their interactions are much more exploratory, and subjects use their entire body for extensive surface contact when under the influence. Effective MDMA doses were analogous with those of humans and rodents.
At the same time, the genome of O. bimaculoides was successfully sequenced to find the gene SLC6A4. This gene is known in humans to be involved with serotonin neurotransmission and transportation. O. bimaculoides carries the gene and the ability to be social, but the neural mechanisms are suppressed until ecologically necessary.
Photo of O. bimaculoides at Santa Monica Pier Aquarium in 2006. Photo courtesy of Jeremy Selan
Dr. Gül Dölen, the lead investigator, summarizes the research: “What our studies suggest is that certain brain chemicals, or neurotransmitters, that send signals between neurons required for these social behaviors are evolutionarily conserved.” She also suggests that more research need to be done in exploring the homology of these lineages as these results are preliminary.
I find it very comforting to know that there is a scientific correlation between humans and octopi. This does not mean you could convince me to go scuba diving tomorrow, but using my interest in genetics and ecology is an effective tactic!
