Diana Fleischman and Geoffrey Miller – Audience Q&A

This is the audience Q&A with Diana Fleischman and Geoffrey Miller at the NYC Rationality meetup, following up on my own interview which you can find here.

Content note: the audience comprised rationalists of many ethnicities, orientations, and gender expressions and we asked questions that could offend many ethnicities, orientations, and gender expressions.

What are the main hypothesized causes of homosexuality?

Diana: There’s a difference between homosexual behavior and homosexual orientation. Homosexual orientation is very rare. There’s one species, domestic sheep, in which 8-10% of rams are not interested in ewes at all. You can tie a ewe in heat in front of them and they don’t react at all. Actually, one area where homosexuality research has flourished is among sheep breeders because if you buy one of these rams who’s gay, that’s really bad news for the business.

So homosexual orientation is exceedingly rare. Even though you see stats that it’s 10% in people, it’s about 3%. In a paper that I wrote I claim that bisexuality is the optimal sexual strategy because sex is not just used for reproduction, it’s also used for affiliation. There are a number of ways to affiliate: you can give somebody food or you can give somebody an orgasm. These are ways to get other people to like you. If you’re somewhat attracted to people of the same sex but not enough to forego reproductive opportunities with people of the opposite sex, then you can actually engage with both sexes.

Is the bisexual revolution coming?

Diana: There are places where people are much more open to it, but not many places. It’s a whole spectrum of behavior.

In places around the world, there are men who have anything from affectionate to sexual interactions with other men and they’re not considered gay. They have homosexual behavior along with heterosexual behavior, and that’s a common thing. If you look at the bell curve of orientation in a society that suppresses homosexual behavior among men, you’ll find that only men who are predominantly homosexual will exhibit this type of behavior. It’s not used for affiliation in our particular society, so men don’t engage in it. Homosexual men are basically just the edge of this bell curve. The reason there keep being a small percentage of men who are exclusively homosexual is because bisexuality is adaptive.

The most controversial hypothesis about the origin of homosexuality is Gregory Cochran’s idea though there’s not much evidence behind it, which is the ‘gay germ’ hypothesis. Now homosexuality is not as hereditary as you may think; if one identical twin is gay his twin would be gay only 50% of the time. But also, identical twins are usually in the same amniotic sac, while fraternal twins are in different amniotic sacs. Cochran shares some evidence that if twins share an amniotic sac, they are more likely to both be gay. So there might be some virus or bacteria that causes homosexuality later in life.

That’s very controversial because the idea is that there would then be some kind of gay vaccine which could prevent women from giving birth to boys who would grow up to be gay. 

Geoffrey: And the reason why it would make sense from the point of view of the virus is that it’s a lot easier to spread since gay men have a lot more sexual partners on average than straight men. 

I have a Ph.D. student studying generally whether sexually transmitted pathogens evolve to manipulate our sexual behavior to promote their spread. This could include lowering our mating standards, making us more promiscuous, more sexual, being sexually active earlier and later in life, all kinds of things. So it might not be us in the driver’s seat as much as we think. 

Diana: There are also ideas about endocrine disruptors and things of that nature. This is all very controversial. I was at a conference with other people, like me, who study homosexuality. And there was a guy there who wasn’t willing to admit that gay men are more feminine than straight men on average, that they’re more likely on average to have feminine interests. And if there’s controversy about something as basic as that, it’s very difficult to talk about anything in this sphere. 

Or, for example, if you give a female rat testosterone while she’s in the womb she’s going to mount other rats when she’s older. And in the 1980s some women took a miscarriage drug that masculinized their daughters and made them more likely to be lesbians. That kind of stuff happens as well and people really hate talking about it.

Is there quantified data on gay men being more promiscuous?

Geoffrey: There are some studies about the average number of sexual partners, the typical results are that sexually active gay men in their 30s or 40s have had several dozen partners, while the average for straight men is closer to 10. The average for women is closer to 10 but they may be lying. And it’s lower for lesbians than for straight women.

But there’s a bit of a taboo around mentioning these results because promiscuity is heavily moralized. Polyamorous people also tend to have more partners than monogamous people. And then conservatives say that poly people are all sluts. Now we are, but in a good way! 

Why do men not have a preference for tall women? Women prefer tall men, and tall women have tall children, some of whom will be sons. So it’s weird that tall women aren’t universally preferred.

Diana: Dutch people are tall and people in Spain and Portugal are short, and there’s evidence that it’s not by accident. There is mixed evidence that there has actually been positive selection for shortness in Portugal and Spain (which is why I’m short). There’s evidence from across the world that men prefer smaller women. Some of that has to do with smallness being associated with youth and neoteny, some of that might have to do with less savory hypotheses about exploitability and controllability. 

It’s probably also associated with fertility. I think that Randy Thornhill said that 5’2” is the optimal height for fertility. Women parlay some of the somatic effort of growing into reproductive effort.

Jacob: In ancient Greece, men preferred tall women. In The Odyssey, Calypso is bewildered that Odysseus wants to go back home since she’s taller than Penelope. And Odysseus admits that she’s taller and more beautiful, but says that he’s still loyal to his family even though they aren’t tall like the gods.

You said earlier that it’s important for people to be conscious of their motivations, and I’ve recently heard two criticisms of that idea. One is Robin Hanson’s idea that if you know your motivations, you’re worse at doing something and convincing people that you’re doing it for the right reasons. The more interesting one is Jonathan Haidt’s idea of divinity, the moral dimension that puts animals below you and the gods above you. The less like an animal you are the more you can make meaning out of your life, or act morally and communally.

Do you think that thinking about motivations like trying to get laid takes away from that?

Diana: To Robin Hanson’s view, it’s an interesting idea that you’re worse at things if you know the motivations. But I can also make myself happier if I’m aware of what’s driving me. I used to date an Effective Altruist who made a lot less money than I did. At the beginning of an evening, I would give him cash so that he could pay for everything through the course of the night. And I would try my best and often succeed in forgetting I had given him cash so that I would feel like he’s taking me out. And that was awesome, but it required being quite cynical about my motivations.

As for Jonathan Haidt, I don’t identify with that notion at all. I can feel very much that I have higher meaning and purposes in my life and still be a mammal, a shitting, gestating, weird body.

I’m curious why you consider altruism a positive signal. I’m asking because I have no morals and no principles and I’m living a very happy life. Potentially the happiest life I could imagine living. Why is altruism so appealing to other people? To me, it seems inefficient.

Diana: Ok, I’m going to talk to you like you’re an alien. 

That’s right, I’m an alien.

Diana: Let’s say you’re in a small group and you want people to exchange with you. You need to signal certain qualities to them that mean that in the long term you’re a good exchange partner. One of those would be loyalty to the group; another is consistency over time. This is very interesting: people change a lot over time but they like to signal that they’re very consistent so they’ll be reliable partners in the future. Altruism signals that you’re willing to be generous to those who are powerless. That is a good and virtuous signal because it also means that you’re a better exchange partner. If someone’s down and out and no longer useful to you, for example, you would still be willing to help them out. 

Geoffrey: I have a whole chapter on this in The Mating Mind, which Diana should read some time *grins*. What I argue there is: imagine that you have two tribes. In one, you signal traits in ways that don’t bring benefit to others, like showing off only by singing which doesn’t bring evolutionary benefits like food or protection to the group. In the second tribe you’re doing cooperative hunting, for example, and bringing back tens of thousands of calories in mammoth meat and distributing it conspicuously within the tribe. Which of these tribes is going to do better in competition?

Jacob: Depends. Is the competition American Idol?

Geoffrey: The concept is that we’re descended from the second tribe. We’re descended from many generations of ancestors that signaled altruism within the group and had these exchange partner benefits within the group but also had net benefits in competition with other groups.

This is not a strict group selection argument, it’s an equilibrium selection argument in the game-theoretic sense. That’s what I argued in The Mating Mind, that we’re an unusually altruistic species because at the tribe v. tribe level the cooperative altruistic signalers did better. And in fact, that was exactly what Darwin argued in 1871. 

Given evolutionary accounts of relationship activities and strategies, the cynical approach tends to have a moralizing effect. Calling what women do ‘shit-testing’ makes it sound like a morally bad thing to do to your partner. But of course, a lot of what we’re doing is good: it strengthens bonds, creates a sense of security, etc. 

I wonder, in your personal life or from an academic perspective, how do you choose when to indulge your evolutionary preferences and when not to?

Diana: I don’t have as much control as people may think. I’m very aware when I’m shit-testing, and Geoffrey will say as much to me, but I still carry on. I can also predict how long I’ll be feeling angry and how long I might feel like shit testing.  

Yes, calling it that makes it sound bad because it generally is bad, not just because it’s a red pill term. When I was shit-testing today I recognized that I was taking the thing that he had done most recently as an indicator of his overall commitment rather than aggregating. It’s much easier for a woman to aggregate all of her grievances than to aggregate all of her joys. It’s because of this error management, it’s much better to err on the side of being doubtful about somebody’s commitment. It can be good to play around with these emotions, but it’s hard to handle them.

Geoffrey: It might be better to use a more neutral term. Amotz Zahavi called it ‘testing the bond’ in his 1975 book The Handicap Principle. 

You mentioned giving a talk about how kink spaces are outlets for evolutionary urges. How would kink be represented in days of yore?

Geoffrey: There are carved images that look like the Venus of Willendorf fertility figures that have indications of rope and bondage going back at least 30,000 years. It’s hard to interpret, but tying women up is what you would do when you raid another village to kill all the men and steal the women. 

Domination/submission dynamics run really deep in primates, generally. Primates have been doing domination and submission signals for at least 60-70 million years. The idea of engineering situations that bring that out seems like a natural thing for social primates to do. 

And as for role play, kids like to pretend to be someone they’re not. And sensation play like spanking and flogging… there’s a speculative theory.

The standard form of copulation for mammals is dorso-ventral rear entry — ‘doggy style’. What that tends to do is put a lot of repeated impact on the female’s back end. So, what you’re getting with flogging is a superstimulus of prolonged extra-hard copulation. It’s a fitness indicator because that would be hard for a male to sustain. 

Diana: There’s another thing about kink, which is that when you’re aroused you have arousal-induced analgesia — you don’t experience pain as much. If you can take a lot of pain, you’re actually giving an honest signal of how aroused you are. 

The top three sexual fantasies for women are: number one, having sex with their main partner *mimes yawning*, number two, sex with a strange man, and number three, being taken against their will, which is now called “rapture play”. So these are things that women have experienced over evolutionary history many, many times. It’s a controversial thing to talk about but if you look at any romance novel there are often interactions where women are taken against their will. 

Geoffrey: I did give a talk in Amsterdam on the evolutionary psychology of BDSM and kink. What I pointed out there is that a lot of what happens in kink in playing around and ritualizing a lot of evolutionary psychology stuff. Likewise, a lot of what happens in role-play — letting those instincts out to play. And that can be wonderful and creative and really really good for a relationship.

I don’t know how many other ev psych people have this view, we don’t really talk about it at the HBES conference. I do think that in the future there will be more openness about it. There will be a view that we can keep these dark instinctual secrets when we go out to our corporate jobs and behave in society, but you can still make space for them to come out and play in private life in safe and creative ways.

While we’re on the subject of kink and strange desires, I found that I have a desire as a woman that makes no evolutionary sense at all. I wonder if you have a theory about it. I have a fantasy about finding a shitty loser that no one likes and have him dominate me. 

Diana: So utilitarian! But would he even know how? It’s actually a very utilitarian activity to have sex with all the men that no one else will have sex with. It would make their year!

Geoffrey: Normally hypergamy works a little differently. Normally a woman would take an existing partner and do some mental trick or role-play to build him up as a kind of superhero. So the status differential between them gets amplified until she feels like Leda and the swan (who’s actually Zeus) and that’s exciting. Taking a total loser and then pushing yourself way below him… I don’t get at all. 

Diana: I’ll just make up a story here. You want to find someone that no one else wants, so you have no competition for him, and then elicit in him the highest status and accomplishment he can have. So you have an ideal situation where you can totally monopolize him because no one else has an idea that he’s good. Women often choose men based on how many other women are attracted to them, but if you choose somebody that you have special knowledge about you never have to share them with anybody. 

Geoffrey: I have an idea. If you’re a teenage girl in an age-stratified school system where you’re only allowed to date and interact with guys your age, they’re all losers relative to actual mature adults. So in order to feel any attraction to these guys you have to be able to see the little bit of promise and potential in them and be able to feel the hypergamy by making yourself even lower than they are. That would be adaptive if that’s all the choice you’ve got available. 

So I think that some women are in a position where the best they can do in terms of finding a partner that they think is a catch, given the constraints that you’re all in 9th grade.



7 thoughts on “Diana Fleischman and Geoffrey Miller – Audience Q&A

  1. Thanks for the very interesting interview!
    Could you or someone else link a source for Dr. Fleischman’s claims about the 3% homsexuals? Specifically, I recall well replicated experiments showing 10% of men react to erotic pictures of women but not of men (I’ll link when I find it).
    I would also like a link for the twin study, if possible.
    Thanks in advance!


  2. I wonder if you have a theory about it. I have a fantasy about finding a shitty loser that no one likes and have him dominate me.

    My simple theory is that human sexual behaviour has a wide variance, and that there are many individual examples that are atypical.


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