People who score highly in the Dark Triad personality traits – narcissism, psychopathy and Machiavellianism – are vain, selfish, callous and manipulative.
They're not the kind of people you want to spend much time with. This raises the obvious question – to put it bluntly, why over evolutionary timescales haven't these people died out?
One possibility is that their traits actually confer short-term advantages in the mating game. Dark Triad people are obnoxious once you get to know them, sure, but perhaps they can be alluring at first, what with their swagger and smooth talking.
To test this, Emanuel Jauk and his colleagues had 46 women and 44 men (average age 23; all heterosexual) fill out personality questionnaires, including measures of the Dark Triad traits, and then take part in speed dating sessions, such that every man and woman in the study enjoyed a three-minute date with each other.
The participants filled out score cards for each person they met, including how attractive a prospect they found them for different relationships (friendship, one-night-stand, "friend with benefits" and long-term romance), and whether they'd like to see them again.
The findings, published recently in the European Journal of Personality, show that men who scored higher in narcissism were rated by women as more appealing for short-term trysts and longer-term commitment, but not as friends. Women were also more likely to say they'd like to see these men again. Scores in the other two Dark Triad traits did not make any difference to the men's success.
Similar to the men, women who scored higher in narcissism also attracted more favourable ratings from their dating partners, for short and long-term relationships, but not for friendships. For women (but not men) scoring higher in psychopathy also went hand-in-hand with receiving more favourable ratings as a potential one-night stand.
Intriguingly, the reasons for male and female narcissists' allure in speed dating seemed to be different.
For men, it was entirely explained by extraversion. Male narcissists tended to score higher in extraversion, and once the appealing influence of extraversion was factored out, narcissism offered nothing more.
By contrast, for women, narcissism correlated with physical attractiveness (as rated by four judges who didn't take part in the dating), and once the appealing influence of physical attractiveness was controlled for, narcissism added nothing. Ditto for women's psychopathy – the appeal was all down to the fact that psychopathy correlated with physical attractiveness.
In short, it seems that narcissism (for men and women) and psychopathy (for women) make people more attractive in the mating game, at least in the context of speed dating among young people, which helps explain the advantage that these traits provide.
But crucially, the reasons for this are not direct, but have to do with other characteristics that correlate with narcissism and psychopathy, rather than with the traits directly.
This raises some interesting questions for future research, such as why are extraversion and narcissism linked in men, and why are attractiveness and narcissism (and psychopathy) linked in women? For instance, does a woman's attractiveness make it more likely that she'll develop narcissistic traits, or do her narcissistic traits make it more likely that she'll put more effort into her appearance?
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