From a gene’s eye view, is it better to be in the body of a machiavellian psychopath or in the body of a socially-responsible nice guy? The answer to that question depends on the environment, and recent evidence suggests that the answer is far from obvious. My debate with Jeremy Yoder comes down to the question of whether or not conscientious sexual choices can change this equation.
In his third and (thankfully) final post critiquing my “Don’t Sleep With Mean People” campaign, Yoder helpfully narrows his scattershot objections down to a simple and easily refuted point:
My argument isn’t that this genetic contribution [to individual differences in meanness] doesn’t exist—it’s that this genetic contribution is pretty much meaningless from the perspective of an individual person’s dating life.
I should note that this is Yoder’s argument now. In his previous post it was about how “natural selection needs genetic variation in order to operate” and Yoder was (or acted like he was) skeptical that differences in meanness are due in any part to genetic variation. Now he acknowledges the evidence that genetic variation does in fact play a role in determining human temperaments, but claims this is irrelevant to selection because our genes are sensitive to environmental triggers:
If genetic variation is only strongly predictive of variation in criminality for people who’ve experienced many environmental risk factors, then you’d have to exclusively date people with those risk factors (this is a filter I haven’t found on OKCupid yet) in order to know that the variation in their personalities is probably due to genetics.
Let’s take a moment to note that my campaign is not titled “Don’t Sleep With Genetically Mean People.” The concept is specifically agnostic about the relative contributions of environment and genes – it doesn’t matter! As I’ve said from the beginning, I’m assuming only that some component in some people is genetic. As long as that’s true, targeting meanness in general will impact both genetically and environmentally caused meanness, by incentivizing good behaviour while reducing the relative fitness of mean genes.
Let’s say a young lady, call her Courtney, were to change her ways and eschew sleeping with bad boys like the guy above. Anytime a prospective lover brags about beating someone up or expresses enthusiasm for street racing or firearms she breaks things off with him. She doesn’t know (or care) which of these guys were exposed to risk factors and which weren’t, which of them have mean genes and which are a “product of their environment.” They all get dismissed in turn, and she ends up settling down with a conscientious, supportive, responsible guy. What’s the worst that could happen? Here’s Yoder’s doom-and-gloom scenario:
You could end up reproducing with someone whose genome is chock-full of variants for “meanness” that are never apparent in the right environment.
In other words, the guy is a prince among men and never mistreats her or anyone else, but he carries latent genes for meanness. So what? She gets a great guy and has a happy life! Genes for aggression that don’t get expressed can’t be targeted by selection (Yoder’s point) but they also don’t increase the rate of spousal abuse or armed robbery (my point). And if those genes manifest themselves as meanness in the next generation due to encountering the requisite environmental triggers, they will be screened out by the next generation of young women who don’t sleep with mean people. Or maybe the carriers will adapt to the new environment (where meanness is suddenly maladaptive), and figure out how to act right. Either way, individuals like Courtney win, humanity wins, and mean people lose (along with Yoder’s argument).
This is not just a cockamamie scheme I cooked up, it’s something that has been happening for tens of thousands of years already. Richard Wrangham and Nicholas Wade have written about the phenomenon of “gracilization” or “self-domestication” in humans and in our close cousins the bonobos. This self-domestication is driven by an evolutionary process in which “the violent and aggressive males somehow had a lesser chance of breeding.” If you agree that a less violent world would be a better one for everyone involved, this transformation is something to celebrate. It is aided by moral philosophy and the rule of law – Geoffrey Miller argues “moral philosophy and political theory have mostly been attempts to shift male human sexual competitiveness from physical violence to the peaceful accumulation of wealth and status.” It is aided by (pop) cultural evolution when peaceable high-status males like Ashton Kutcher inform screaming female fans that sexiness consists of being “intelligent, thoughtful, and generous.” And I hope it is aided, in some small way, by my campaign.
When Jeremy Yoder first started sniping at me I thought he was just being an annoying pedant, but I’ve been flabbergasted to discover that he truly believes mate choice makes no difference to human behaviour, and individual sexual choices could not, under any circumstances, make future generations perceptibly, genetically nicer. How on earth could a practicing biologist adhere so tenaciously to this position? Does he really think male-on-male aggression is sexually selected in every mammal species except ours? Yoder is clearly not a blank-slatist, so in the end I can only return to my original “ad homo-nem” diagnosis (with apologies to Jesse Bering). Like the grinch that stole Christmas, Yoder is mad at my “heteronormative” campaign because he feels left out of it as a gay man. His mate choices are very unlikely to influence genes via sexual selection, so he argues that sexual selection “is pretty much meaningless from the perspective of an individual person’s dating life.”
Confidential to JY: if you had just expressed your outrage by saying “I feel hurt and left out” instead of accusing me of peddling pseudo-science, we could have avoided all this ugliness.
My only consolation for Yoder is to point out that we are virtually in the same boat. Because violence is mostly perpetrated by heterosexual males, it’s heterosexual female mate choice that has the greatest chance of changing the evolutionary equation. Peace-loving males like Yoder and I are cheerleaders at best, arguing about the details while female mate choice continues its slow but relentless reshaping of the human genome. I have no delusions that I can change its course, but that doesn’t stop me from wanting to give it a nudge.