Why we like bad boys: they’re better at dressing up

What is it that makes the "bad boy" so appealing? From James Dean in Rebel Without a Cause to Marlon Brando in Cat on a Hot Tin Roof, we've idolized the guy we know is trouble, but for some reason we simply cannot resist him. Do we want to save him? Change him? Get swept away in the drama of his more exciting life?

Now a new study suggests that in fact, it's something much simpler: he's hot.

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In a study published in the journal Social Psychological Personality and Science titled "People With Dark Personalities Tend to Create a Physically Attractive Veneer", researchers from Washington University in St. Louis suggested that people with "Dark Triad" character traits that might make someone a bit of a bad boy — Machiavellianism, narcissism and psychopathy — are better at making themselves appear attractive than those that lack these negative personality traits.

Scientists first gave personality tests to 111 subjects to see who had these "Dark Triad" character traits, reports Scientific American. Then they photographed each participant, first in their "adorned condition", wearing their own clothes and make-up with their hair done, and smiling or posing as they chose. In the next "unadorned condition" photograph, participants wore no makeup, long hair was pulled back, and everyone was dressed in the same grey sweatpants and T-shirts to look as neutral as possible. They were told to remain expressionless.

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Volunteers then rated the photos for attractiveness. Those who had Dark Triad traits were found to be significantly more attractive in their adorned state than in their unadorned state, but those who didn't suffer Dark Triad personality defects did not experience the same boost when in the adorned state.

So what does this mean? Are we falling for the wrong people simply because they're better at making themselves look pretty when they're not? An article on PopSci put it this way: "Mean people are just as ugly as the rest of us, they're just better at fooling everyone into thinking they're hot." Over at The Huffington Post, the consensus seems to be "If you just can't ever get your hair to look right, take heart: At least you're less likely to be a psychopath."

But before we start casting aside all of our attractive friends for fear of their mental deficiencies, it should be noted that at least one expert doubts whether this study reveals much of anything.

"The way they've identified these characteristics is problematic," says David Mensick, a psychologist and professor at Dalhousie University. "That's not the way I would do it."

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Menick is talking about the specific traits that were selected for the study.

"The terms Machiavellian and psychopath have no psychological relevance," says Mensick, "and so conclusions made using these methods are suspect."

He takes special issue with one line in particular: "This study provides the first experimental evidence that dark personalities construct appearances that act as social lures—possibly facilitating their cunning social strategies."

"To me, this is imputing that there is something negative in the personalities of attractive people," says Mensick. "It's saying that they're using their attractiveness to to draw people to themselves and then be mean to them."

Mensick believes that the reasons people are drawn to potentially destructive relationships are far more complicated than the lure of an attractive veneer.

So while this study may indicate that those bad boys are a little less attractive in sweatpants, don't write yourself off as superficial if you can't resist their siren call — the attraction may be a little more complicated a pretty face.