“Love is merely an excuse DNA uses to reproduce itself.” It’s a good line. I gave to a space alien in Gene Roddenberry’s Andromeda 20-odd years ago, and it still rings true. More so all the time.
If you’ve been following along, you know I’ve been at war with my love addiction lately. So far I’m winning, but it’s one day at a time. Thanks for hanging in with me. Instead of continuing to moan about my psychic pain for yet another column, I thought I’d share with you a fascinating bit of scientific research I just encountered, an unlikely (if slightly tangential) confirmation of my opinion that most of this love stuff, especially the addictive part, is simple physiology.
Researchers at Nagoya University in Japan spent years studying Drosophila — aka fruit flies, the rock stars of genetic testing — and noticed that two different Drosophila species had slightly different courtship behaviors. D. melanogaster males wooed females by rubbing their wings together to make a noise. D. subobscura, however, woos a female by regurgitating food for her.
While wing rubbing and regurgitating food may not sound terribly romantic, think of them in terms of those five Love Languages people put in their dating profiles: Words of Affirmation, Quality Time, Acts of Service, Receiving Gifts, and Physical Touch. Melanogaster is using Words of Affirmation. Subobscura is Giving Gifts. Their behaviors diverged genetically millions of years ago, and a male D. melanogaster would no more court a female D. melanogaster with food than a human female would court a human male by waving her swollen red butt at him like a baboon.
Okay, maybe some human females…
The point is, the two species have totally different mating behaviors that are passed down from generation to generation (a fruit fly generation is about 10 days) and the scientists wondered if there was a genetic connection. Was this behavior pattern just a behavioral social norm, or was it perhaps written in the DNA and hard-wired into the fruit fly’s brain? After years of study and observation, they pinpointed a single gene they believed was controlling mating behavior.
So they did some gene editing. They essentially swapped out one gene between their melanogaster fruit flies and their subobscura fruit flies. You already know what happened, or else I would not be writing about it here. Yes, the affirmation dudes started upchucking their food and the gift-givers began to sing. Their romantic behavior wasn’t a choice. It wasn’t learned at church or from Shakespeare’s plays — it was coded in their DNA.
This raises the question, how much of this applies to humans? Is your anxious attachment style a result of your mommy not hugging you enough, or is it a random strand of DNA? Or - and I suspect this will turn out to be the case — is it a synergy between the two?
There’s another fairly new area of psychobiology known as epigenetics, which posits that our genetic traits are not fixed but can be “switched on and off” by outside influences. You may be hard-wired for a propensity to love addiction, but whether that genetic switch is flipped depends largely on early childhood experiences. This is why you’re an addict and your sister is a black-belt Alanon. (Speaking from personal experience, here. Hi, sis!) Maybe mom smoked during one pregnancy and not the other. Or maybe dad was super stressed for that first child and not the second.
Or maybe some space alien scientist came along with CRISPR shears and swapped out some DNA, just for giggles.
More will be revealed, as the AA literature says. But it is looking like that saying "Genetics loads the gun, environment pulls the trigger” (attributed to everyone from Mehmet Oz to Michael J. Fox, by the way, which I find amusing) is going to prove true for everything from alcohol use disorder to compulsive shopping. To, apparently, regurgitating food for your prom date.