When I was looking in the mirror the other day, a few questions popped in my head: Why do we have eyebrows? What exactly is the purpose of those two swaths of hair? And what would happen if we didn’t have them?
It was time for a little digging. Hooray!
Before we humans evolved to the point we’re at today, we had fuller eyebrows. Actually, they looked more like a unibrow. Our foreheads were also much more pronounced and jutted out over our eyes. Now our foreheads extend just slightly over our eyes, and our eyebrows have a more refined look to them. But they still serve the same purpose.
One key purpose of our eyebrows is to protect, well, our eyes. They do this by helping to prevent rain and sweat from trickling down and blurring our vision. But there’s more to it than that. Because of their slightly arched shape and the direction in which the hairs lay, our eyebrows can filter any liquid rolling down our forehead towards our temples rather than our eyes. Pretty cool, eh?! Since vision is a one of the five senses we heavily rely on, it’s really important that we can use it to the fullest extent possible.
Eyebrows play a big role in nonverbal communication as well. When we’re surprised, our eyebrows automatically raise up. And when we’re upset or annoyed, we tend to lower them. Generally speaking, we don’t put any effort into what our eyebrows are doing. They’re pretty good at indicating how we’re feeling all on their own.
Our eyebrows have another, slightly unexpected purpose: facial recognition. Sure, people may recognize you by your eyes and your smile, but if you shaved your eyebrows off today, people would find it more difficult to recognize you. Huh? Who woulda thunk it.
As we’ve discussed here before, our bodies frequently offer subtle clues when something is amiss, and our eyebrows are no exception. For example, in Thyroid: Guardian of Health, Philip G. Young explains that a common sign of hypothyroidism (low thyroid function) is the thinning out or even complete disappearance of the outer third of our eyebrows.
So what would happen if we didn’t have eyebrows? Well, for starters we’d have to wipe off our foreheads more frequently to keep stuff from getting in our eyes. People would have a harder time understanding how we’re feeling in any given moment. And they’d have to take more time figuring out who we are in the first place.
Thank you for all of your hard work, eyebrows. I’ll never question your existence again. 🙂
Image from iStock/ajr_images.