What Our Thick-Brow Obsession Has to Do With Feminism — and Science

Eyebrows are perhaps one of the most divisive — and talked-about — features of the human face. (Photo: Getty Images/GIF: Samantha Bolton for Yahoo Health)

Cara Delevingne’s eyebrows — which have their own Twitter handle — make the headlines almost as often as the model herself. Earlier this year, a BuzzFeed article went viral that showed celebrities — Delevingne included — who were Photoshopped without their brows. Recent Bachelor contestant Carly Waddell was bullied on the Web for her thin eyebrows — a side effect of hypothyroidism, she revealed on Twitter — and then received praise from the Internet masses when she showed up on Bachelor in Paradise with thicker brows.

We’re a country obsessed with eyebrows. But why?

At face value, eyebrows might seem to serve the same purpose as eyelashes: keeping dust, dirt, and rain out of our eyes. Why else would we have a random swath of hair across our forehead? Think of your brows as a natural sweatband of sorts: “Your eyebrows are really meant to deflect sweat away from your eyes,” says Jean Carruthers, MD, a clinical professor of ophthalmology at the University of British Columbia. “They’re definitely a protective mechanism.”

For more on the evolutionary reasons we have eyebrows, watch the video below:

But perhaps more important, eyebrows also have a social function (and, no, we don’t mean uniting us all on Twitter to swoon over a supermodel’s impeccable brows). Because they’re critical for emotional expression, as well as facial recognition, we’re all subconsciously cued in to each other’s brows: how and when they move and what they look like. As a result, we place a lot of stock in changes to their shape, color, and size, says Javid Sadr, an assistant professor of psychology at the University of Lethbridge in Canada.

In fact, eyebrows may be a sort of facial signature — a way of distinguishing one person’s mug from another’s. In 2003, Sadr and his fellow researchers conducted a study, published in the journal Perception, where they showed people 25 images of celebrities without eyebrows, and then another 25 snapshots of celebrities without eyes. Interestingly, the study participants correctly identified about 56 percent of the eyeless celebs, but only 46 percent of those who were brow-free. The study’s conclusion? Eyebrows are even more important than eyes for recognizing people.

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Some researchers have even compared the human face to a barcode, an alternating sequence of dark and light — the pale flesh of the forehead, followed by darker brows, then the whites of the eyes, and, finally, the darker-colored lips — creating a unique pattern that helps us identify one another. “If the eyebrows aren’t there, it really messes up the way the visual system is designed to find and process faces,” Sadr tells Yahoo Health.

The role of eyebrows in facial recognition may help explain why models with distinct brows — think Cara Delevingne (again!) and Cindy Crawford — often rise to the top. Since females naturally have more arched, thinner, and higher-set eyebrows than men, a woman who embraces a more masculine brow will inevitably stand out, explains Izzat Jarudi, a co-author of the Perception study.

“I don’t think you’ll find any models going for the Frida Kahlo unibrow,” adds Carruthers, who wrote a journal article about the social significance of eyebrows, “but just a little bit thicker [than the female norm], just a little bit less arch — that’s definitely going to get you attention.”

Breaking the brow mold, however, doesn’t always equate to being more traditionally attractive (although we can all agree Delevingne is stunning). Typically, “what happens in cosmetics” — tweezing, waxing, shaping — “exaggerates those [gender] differences,” Sadr says. In other words, when a woman thins her eyebrows and creates an arch, she’s playing up the natural feminine shape. As a result, “the eyebrows become a much stronger signal of a person’s gender,” he says. “And what we almost always find is when you accentuate male-female differences, the person becomes more attractive,” which is yet another reason we may be inclined to obsess over brows.

The recent wave of ever-thickening eyebrows may also be a reflection of an increasingly feminist culture. Sadr compares the Delevingne look to the big shoulder pads on women’s suits that became popular in the 1980s. “There was a big movement of more women in the workplace and more women breaking through the glass ceiling,” he says. “[Big shoulder pads] were a masculinizing feature. They made a statement about women being empowered.”

Likewise, if thick brows prove to be more than a passing fad, they may come to represent women’s rebellion against society’s expectations of traditional femininity — or even a break from the sexual double standard since, historically, well-groomed brows have been in vogue during more conservative eras, says Carruthers. Bushy brows are animalistic — a quality with sexual connotations usually reserved for men.

Related: 7 Things Your Body Hair Says About You

But it’s not just the appearance — bushy vs. thin — that we notice. We’re also attuned, albeit more subconsciously, to the movements of one another’s eyebrows, which help convey exactly how we’re feeling, often more honestly than the rest of our face. (In fact, scientists have found that there are only seven visibly distinct ways the eyebrows move — and five of those are involved in the expression of emotion.) Although we can control, to some extent, the movements of our mouths, “what we’re doing with our brows is almost involuntary,” says Carruthers. “If someone surprises you with a comment, your brows go up. You almost can’t help it.”

Our eyebrows are critical for conveying anger and fear, emotions that, unlike happiness, aren’t always easily readable from the shape of the mouth. “If you were to shave your eyebrows, the same expressions wouldn’t carry much of a signal,” Sadr says. “That dark line really accentuates the movements of the skin and muscles.” And since we tend to mimic the eyebrow signals of others, our brows help us empathize, too. (This is why folks who’ve received Botox injections may struggle to read the emotions of others.)

“They’re such powerful message givers,” Carruthers says. “The eyebrows show whether you’re female or male, whether you’re young or whether you’re older, whether you’re interested, dissatisfied, angry, curious, or incredulous. Eyebrows really are our big signalers.”

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