The "Super Uncles" of Samoa

Male homosexuality doesn’t make complete sense from an evolutionary point of view. It appears that the trait is heritable, but since homosexual men are much less likely to produce offspring than heterosexual men, shouldn’t the genes for this trait have been extinguished long ago? What value could this sexual orientation have, that it has persisted for eons even without any discernible reproductive advantage?

One possible explanation is what evolutionary psychologists call the “kin selection hypothesis.” What that means is that homosexuality may convey an indirect benefit by enhancing the survival prospects of close relatives. Specifically, the theory holds that homosexual men might enhance their own prospects by being “helpers in the nest.” By acting altruistically toward nieces and nephews, homosexual men—bachelor uncles in effect—would perpetuate the family genes, including their own.

Two evolutionary psychologists have been testing this idea for the past several years on the Pacific island of Samoa. Paul Vasey and Doug VanderLaan of Lethbridge University, Canada, chose Samoa because male homosexuals there—called fa’afafine—are widely recognized and accepted as a distinct gender category, neither man nor woman. The fa’afafine tend to be effeminate, and to be exclusively homosexual. This clear demarcation makes it easier to identify a sample for study.

The researchers have shown in past research that the fa’afafine behave much more altruistically toward their nieces and nephews than do either Samoan women or heterosexual men. They babysit a lot, tutor the kids in art and music, and help out financially—paying for medical care and education and so forth. That’s interesting in itself, but it’s unclear just why they behave this way. What’s going on cognitively that supports such avuncular acts. In their most recent study, the scientists set out to unravel the psychology of the fa’afafine, to see if their altruism is targeted specifically at kin rather than kids in general.

They recruited a large sample of fa’afafine, and comparable samples of women and heterosexual men. They gave them all a series of questionnaires, measuring their willingness to help their nieces and nephews in various ways—caretaking, gifts, teaching—and also their willingness to do these things for other, unrelated kids. The findings, reported on-line this week in the journal Psychological Science, lend strong support to the kin selection idea. Compared to Samoan women and heterosexual men, the fa’afafine showed a much weaker link between their avuncular behavior and their altruism toward kids generally. This cognitive disconnect, the scientists argue, allows the fa’afafine to allocate their resources more efficiently and precisely to their kin—and thus enhance their own evolutionary prospects.

But these aren’t your garden variety uncles. From an evolutionary perspective, you can’t make up for not having any offspring just by giving a toy to your nephew, or tossing a football with your niece once in a while. Indeed, to compensate for being childless, each fa’afafine would have to somehow support the survival of two additional nieces or nephews who would otherwise not have existed. In short, the fa’afafine must be “super uncles” to earn their evolutionary keep.


Do these findings have any meaning outside of Samoa? Yes and no. Samoan culture is very different from most Western cultures. Samoan culture is very localized, and centered on tight-knit extended families, whereas Western societies tend to be highly individualistic and homophobic. Families are also much more geographically dispersed in Western cultures, diminishing the role that bachelor uncles can play in the extended family, even if they choose to. But in this sense, the researchers say, Samoa’s communitarian culture may be more—not less—representative of the environment in which male homosexuality evolved eons ago. In that sense, it’s not the bachelor uncle who is poorly adapted to the world, but rather the modern Western world that has evolved into an unwelcoming place.

For more insights into human nature, visit the “Full Frontal Psychology” blog at True/Slant. Excerpts from “We’re Only Human” appear regularly in the magazine Scientific American Mind. Wray Herbert’s book, On Second Thought: Outsmarting Your Mind’s Hard-Wired Habits, will be published by Crown in September.

A warm glow in Bangkok

Say you are traveling in a foreign country, trying to find your way through the bustling capital city. Not Paris or London, some place a bit edgier. Bangkok. You don’t speak the language, and you’re a little frazzled. You walk into a café for some respite, and to your surprise to see a fellow you know from back home sitting at a corner table, sipping coffee. He’s hardly a friend, but you know him to say hello. How do you feel? Well, after the initial surprise, you probably feel a warm glow as you walk up and greet him. You’re genuinely happy to see his familiar face in this strange place. He’s like an old friend.

Now, simply switch cities. You’re back at home and the same basic scenario takes place: You walk into a café, and there’s the same acquaintance, sitting at a corner table sipping coffee. How do you feel today? Well, if you’re like most people, you don’t feel much of anything. You recognize him, but no smile comes to your face. You might nod hello, but you’re really more focused on getting your morning coffee.

Same face, similar scenario. So what’s going on here? Are you a couple of hypocrites? Well, don’t feel bad. First of all, he’s probably not feeling all that warmly toward you either. And what’s more, your own mixed feelings are probably beyond your control. That warm glow of recognition may be hard-wired into your neurons, but it’s also tightly entwined with other emotions, notably fears about personal peril and a yearning for safety.

At least that’s a theory, which a team of cognitive psychologists have recently been testing in the laboratory. According to Marieke de Vries of Radboud University Nijmegen, in the Netherlands, people naturally feel good when they see something recognizable and familiar. That’s because things that are familiar are—generally speaking—less risky. This is the same impulse that makes us buy the same soap or automobile over and over again: It’s worked in the past, so it’s likely a safe bet again today. With recognizable people, that positive feeling, that sense of comfort, often feels like a warm glow.

But it may not be quite that straightforward. De Vries and her colleagues wondered: Wouldn’t the power of familiarity depend somewhat on the context? Specifically, isn’t it possible that mood might modify and shape the mind’s response to familiar and unfamiliar things? Is that what’s occurring when you feel a warm glow in Bangkok and a big yawn back home? They decided to explore this idea experimentally.

Instead of using people’s faces, the scientists used abstract patterns of dots. Basically what they did is familiarize volunteers with some patterns and not others; then they measured their responses when they saw the familiar patterns later. But they didn’t simply ask them which ones they liked and which ones they didn’t; in addition to doing that, they attached electrodes to their faces to detect subtle physiological signs of smiling. In other words, they measured the body’s visceral response to familiarity and novelty.

But before doing this, they manipulated each volunteer’s mood. They asked some to think of sad events in their lives, and others joyous events; and then they played mood-appropriate music to maintain the gloom or happiness. The idea was that mood “tunes” the mind toward safety concerns. That is, if our mood is good, we assume we must be in a safe place; if we’re feeling edgy or down, that must be because we’re threatened in some way. The researchers predicted that feeling blue (and therefore unsafe) would make familiarity an especially potent cue; feeling happy (and therefore safe) would make that cue much less significant.

And that’s precisely what they found. As reported on-line in the journal Psychological Science, the volunteers who were melancholy smiled much more at the familiar patterns than did those who were upbeat. Think about that: Familiarity wasn’t all that important to people who were already feeling secure; they already had the safety of their local coffee shop. But people who were feeling uneasy and threatened experienced familiarity as very comforting—even when the familiar stimuli were nothing more than meaningless abstract patterns of dots. No wonder the face of an “old friend” can seem so welcoming in a Bangkok café.

For more insights into the quirks of human nature, visit the “Full Frontal Psychology” blog at True/Slant. Excerpts from “We’re Only Human” also appear regularly in the magazine Scientific American Mind. Wray Herbert’s book, On Second Thought: Outsmarting Your Mind’s Hard-Wired Habits, will be published by Crown in September.