It seems beauty isn’t all in the eye of the beholder after all. Researchers have shown women rate a man as more attractive after they’ve seen another woman smiling at him. By contrast, being a jealous bunch, male observers rate a man as less attractive after they’ve seen a woman smiling at him.
Benedict Jones and colleagues at Aberdeen University’s Face Research Laboratory first asked 28 women and 28 men to rate the attractiveness of several pairs of male faces. Next they were shown the same pairs again, except this time one face in each pair was shown with a woman’s face staring at it from the side, either with a smiling or neutral expression. When the participants then rated the male faces for a second time, their ratings had changed for those male faces that had been stared at by a woman.
Female participants rated a male face as more attractive after it had been stared at by a smiling woman, but less attractive if a woman with a neutral expression had stared at it. By contrast, the male participants showed the opposite pattern, tending to rate a male face as less attractive after they’d seen a smiling woman looking at it.
The researchers said this shows our preference for a man’s face is affected by social cues we pick up from how other people look at him. Apparently a similar phenomenon occurs in the animal kingdom — for example female zebra finches prefer a male who they’ve previously seen paired with another female.
This reflects the fourth rule of seduction purported by Robert Greene in his Art of Seduction (which I've sumarised here for ease of reference):
Appear to be an Object of Desire
Few are drawn to the person whom others avoid or neglect; people gather around those who have already attracted interest. We want what other people want. To draw your victims closer and make them hungry to possess you, you must create an aura of desirability — of being wanted and courted by many. It will become a point of vanity for them to be the preferred object of your attention, to win you away from a crowd of admirers. Manufacture the illusion of popularity by surrounding yourself with members of the opposite sex — friends, former lovers, present suitors. Create triangles that stimulate rivalry and raise your value. Build a reputation that precedes you: if many have succumbed to your charms, there must be a reason.
For more information, check out:
Jones, B.C., DeBruine, L.M., Little, A.C., Burriss, R.P. & Feinburg, D.R. (2007). Social transmission of face preferences among humans. Proceedings of the Royal Society B, published online (open access).