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Sigmund Freud famously confessed he had no idea what women want. Charles Darwin, however, had a hunch. He thought that women, like other creatures, want to propagate their genes. Where it gets interesting is how they figure out what kind of man to look for. Sure, most women like a man who is sincere and able to make them laugh, but the story gets more complicated. Women's preferences vary over their menstrual cycle and whether they are looking for a short-term mate or a long-term partner, which, in turn, also depends on the time in the menstrual cycle. When looking for a short-term mate, women can use visual cues such as his shoulder-to-waist ratio, the angularity of his face, or the presence of facial hair. These features each woman can assess for herself; she does not need advice from her girlfriends. When looking for a long-term partner, however, her task is more difficult. A man's appearance or his behavior on a date do not broadcast his ability and willingness to invest resources in offspring that is presumably his. The woman actually needs to get to know him before she can make a sound judgment. Or does she?
A woman looking for a good man can use the old conformity heuristic. When in doubt do as others do (and not only in Rome). For decades there has been plenty of evidence of conformity among humans, much of which has been thought to discredit their rationality. Solomon Asch, for example, showed that many people conform, at least some of the time, with outrageously mistaken judgments made by a unanimous majority of others. Such findings suggest that humans are prone to a crowd mentality. Some psychologists argue, however, that it is adaptive to conform if it appears that others are acting on information that is not available to the person and if conformity saves the cost of going out and getting the information for oneself.
This is where choice copying in mate selection comes in. The basic idea is that females looking for a male partner are, in part, swayed by a male's ability to attract other females. If this happens, if other women flock to some men just because other women do, two related phenomena familiar from folk psychology begin to make sense. First, as some men have noticed, their stock in the dating market paradoxically rises when they are committed; second, some women are concerned about losing their men to other, "raiding," women.
Until recently, the only evidence for choice copying came from animal studies using such exotic species as grouse or guppies. What about humans? I found some interesting references in a popular book on social networks ("Connected" by Christakis & Fowler, 2009). The first study by Eva and Wood (2006) tested the choice copying effect by asking women to judge pictures of men. The same men were rated as more attractive when labeled married than when labeled single. That's the effect. A man who has been "validated" by another woman becomes more attractive. The effect is also specific. The desire to be friends with a man depends only slightly on an endorsement by another woman, and the expectation of being able to work with him as a colleague is not affected at all.
The second study (Waynforth, 2007) produced two effects, one of which already well-known and the other being a statistical artifact. Women first rated the attractiveness of men who were shown alone. Then they re-rated them when shown along with a picture of a woman. The familiar effect was that men benefit from being seen with an attractive woman and suffer from being seen with an unattractive one. The statistical artifact was that those men who were initially rated as unattractive showed the largest gains, and those who were initially rated as highly attractive showed the largest losses. This sort asymmetry is known as regression to the mean since the time of Sir Francis Galton. More interestingly, the study also revealed that choice copying decreases with a woman's sexual experience. Experienced women more confidently rely on their own judgment when picking a man.
The third study was the most intriguing. Jones and colleagues (2007) showed pairs of photos of men of average and equal attractiveness (thereby avoiding the dreaded regression effect). Between the men, they placed a photo of a woman who was looking at one man and who was either smiling or not. Female participants judged those men who were smiled at as most attractive and those who were not as least attractive. This is clear evidence for choice copying. Perhaps more surprisingly, the opposite was true for male judges. Following Darwin, Jones and collaborators speculated that men, more so than women, are worried about within-sex competition. To men, other men who attract beautiful women are scary.
The fourth study was conducted in the Gilbert-&-Wilson research program on affective forecasting (Gilbert and colleagues, 2009). Gilbert and his team are always eager to demonstrate prediction errors, and here they found one in the context of speed dating. Most women in their study thought they could best predict how they would feel about a man they were going to talk to for 5 minutes if they considered his picture and written profile (which contained information about his age, height, music preferences, and such). In fact, a report by another woman who had just speed-dated this man was a much better clue. This study supports the idea that conformity is adaptive when the people we conform to actually possess relevant information. In this particular study, it was likely that the first female dater's reported enjoyment incorporated important elements that did not appear in the man's profile (e.g., his odor or body language). As usual, Gilbert and colleagues found the mot juste to go along with the story. La Rochefoucault advised "Before we set our hearts too much upon anything, let us first examine how happy those are who already possess it."
Interesting as it is, the work summarized here has one glaring hole. What about men? Do men engage in choice copying? Although I have no empirical evidence and only the ghost of Charles Darwin to appeal to, I think that overall the effect would be weaker among men. Why? Consider the difference in the certainty of parentage. Virtually all women know if their children are biologically theirs, whereas men can be haunted by visions of cuckoldry. The men may be present at birth, but the babies emerge from the mother's body. It follows that a woman who has children with a man who also has children with other women still knows what is happening to her genes. A man who courts a woman who is also courted by many others multiplies his uncertainties if there are children. In short, men have a disincentive to copy choice.
It looks good for the women then. By copying choice they save the cost of doing their own research to find the best man. Only at the limit, there is a hidden cost. If too many females gather around a few lucky males, even these lucky ones may be overwhelmed. Or, more prosaically, a man may say no to a woman who is attracted to him because of his attachment to another. The hidden cost to females is that those who rely on copying too much could end up without a partner.
Before we bemoan the costs to females, we must remember that those who pay the highest price for female choice copying are those males who do not trigger the herding effect. Female choice copying is one process that creates polygyny, and in a polygynous population the real losers are the many men who are left without any offspring. The ability of some males to claim a disproportionate number of females cannot be fully explained by the dominance or ruthlessness of these males. It may entirely be matter of female choice and female copying.
So what to do? In the movie "A beautiful mind," troubled genius John Nash-played by Russell Crowe-offered a solution (I don't know if this scene is based on a real event). Nash and two buddies are hanging out at a campus bar when four women walk in. Three are average looking, one is stunning. Each man's impulse is to ask the pretty one to dance. No choice copying necessary here. Nash, however, counsels that the three men ask the other girls to dance, leaving the pretty one without a partner. That way, each man (and three of the four women) get to dance. In contrast, if all men vie for the pretty woman only one couple will end up dancing as the other women will refuse to be second choice. For those interested in game theory, it may be puzzling that Nash counseled collective cooperation when his own theory proved that to be an unstable state. I am therefore afraid that it is pointless to plead with women not to pursue the rock stars and quarterbacks while ignoring the rest of us.
If pleading is no good, what should men do? The research on choice copying suggests that they might use priming. Just as waiters, waitresses, and panhandlers seed their tipping or donation jars with a few dollar bills, amorous men could stage female interest in them with the help of a well-meaning friend, roommate, or perhaps even sister. Far be it from me to actually recommend such a ploy. Deception is deception, and in the end, most women place a premium on sincerity.
Here are the articles on which I based this essay.
Eva, K. W., & Wood, T. J. (2006). Are all the taken men good? Canadian Medical Association Journal, 175, 1573-74.
Waynforth, D. (2007). Mate choice copying in humans. Human Nature, 18, 264-71.
Jones, B. C., DeBruine, L. M., Little, A. C., Burriss, R. P., & Feinberg, D. R. (2007). Social transmission of face preferences among humans. Proceedings of the Royal Society B 274, 899-903.
Gilbert, D. T., Killingsworth, M. A., Eyre, R. N., & Wilson, T. D. (2009). The surprising power of neighborly advice. Science, 323, 1617-19.
In this article, you can find arguments for the potential rationality of conformity, obedience, and doing nothing.
Krueger, J. I., & Massey, A. L. (2009). A rational reconstruction of misbehavior. Social Cognition, 27, 785-810.
This is the reference to the book on social networks.
Christakis, N. A., & Fowler, J. H. (2009). Connected: The surprising power of our social networks and how they shape our lives. Little, Brown & Company.
