The Eyes Have It: Limbal Rings and Attraction
A dark ring around the iris of the eye makes men appear more healthy and attractive.
“Beauty is in the eye of the beholder” is a common saying, intended to capture the idea that aesthetic standards are subjective. A face that one person perceives as alluring, may be found by another to be unattractive.
But what about the eye of the beheld? Do we judge attractiveness based on the appearance of the eyes themselves?
During conversation, we focus on the eyes of others. We use our eyes to communicate our feelings and our interest. But surprisingly little research has been conducted into how eyes are implicated in attraction, at least compared to the heaps of research into the attractiveness of the face, the voice, and even body odor.
Mitch Brown and Donald Sacco of the University of Southern Mississippi stared the problem directly in the eye (sorry) and conducted a series of studies, the results of which were recently published in the journal Personality and Social Psychology Bulletin.
Brown and Sacco took a set of facial photographs that had been manipulated to enhance one very specific part of the eye: the limbal ring. This is the dark circle toward the edge of the colored part of your eye, known as the iris. Our limbal rings are darker when we’re young, fading and blurring as we age. Limbal rings may also be an indicator of the health of a person’s heart and circulatory system, because they are darker in those who have low levels of phospholipid accumulation — a risk factor for cardiovascular disease.
In 2011, a team of researchers from the University of California at Irvine found that a darkened limbal ring is more attractive. But does it also signal healthiness?
In Brown and Sacco’s study, a group of 150 men and women looked at the facial photographs, including the original versions and the versions with the enhanced limbal rings. Each of the volunteers rated the faces for attractiveness on a 7 point scale. The results showed that darker limbal rings did indeed make a face seem healthier.
The Female Gaze?
However, the effect of the limbal rings on apparent health depended on the sex of the beholder and of the beheld. Women thought faces with dark limbal rings were more healthy than those without, but male raters couldn’t see the difference. Men rated faces with and without limbal rings equally healthy.
Why might this be? Brown and Sacco think it could be because women have to be more careful than men about their choice of partners. After all, for our female ancestors a one night stand might have led to an energetically intensive pregnancy, a dangerous childbirth, and a time-consuming rearing period. Our male ancestors, however, unhindered by today’s child support laws, could have avoided the obligation to invest in their offspring altogether. This, among other reasons, may have led women to evolve a risk-averse mating strategy. One component of this strategy may be to only mate with men who meet a relatively high threshold of attractiveness. The lack of a limbal ring could drop men below this threshold and rule them out of contention. Men, meanwhile, might be less… discerning when it comes to judging women for a date.
And what about the sex of the faces themselves? Well, women’s apparent health was unaffected by their limbal rings. Men, though, appeared healthier with limbal rings than without. Brown and Sacco speculate that, because the female hormone estrogen protects against cardiovascular disease, the limbal ring may not be a great cue to health among reproductive aged women. Still, I wonder if the opposite might be true. The absence of a limbal ring in a reproductive aged woman might be a clearer clue to her poor health than it would be in a man, precisely because the majority of young women possess dark limbal rings.
Further studies by Brown and Sacco revealed that priming women to think about romantic relationships makes them rate a man without limbal rings as less healthy, and that women find a dark limbal ring more attractive when judging men for a short-term rather than a long-term relationship.
Brown, M., & Sacco, D. F. (in press). Put a (limbal) ring on it: Women perceive men’s limbal rings as a health cue in short-term mating domains. Personality and Social Psychology Bulletin. doi: 10.1177/0146167217733072