I’m obsessed with eyebrows—as a fact, that's been well-documented. I’m fascinated with testing the best products and finding the most natural-looking shape, that’s a given, but I’ve lately also found myself equally as interested in researching their history.

Why are brows so important to us? What are all the bizarre facts I never knew about my favorite accessory? Well, after a few too many 4 a.m. Google deep-dives, I have the answers. (Well, that, and the knowledge I gained after chatting with a couple of my favorite brow experts on the subject.)

1. Your Brows Can Have Cowlicks

“Oftentimes eyebrows have cowlicks just like we have on our head. This is more likely to happen if you have wavy or curly hair, although it can also happen on those with straight hair. This is especially important to know because when you are trimming the brows, you need to trim in the direction that the hairs are growing. When you isolate a cowlick, you must notice the wave pattern or the direction it's growing in and work accordingly.” –Tonya Crooks, celebrity brow expert

2. Your Brows Are More Active in the Summer

“Your brow hairs grow faster in the summer because of the warm weather and the fact that we’re more active. In the winter they slow down.” –Elke Von Freudenberg, celebrity makeup artist and brow specialist [Editor’s note: Yet another reason to take a warm-weather vacation.]

3. Your Brows Give You Better Vision

The shape of your brow bone and the brows themselves keep rain, moisture, and sweat away from your eyes so your vision stays clear. It's the reason you have eyebrows.

4. Brow Gel Wasn’t Always a Thing

“Brow gel is a recent thing. Today’s brows are a more groomed version (well-shaped and trimmed) of the thick, full brows from the ’80s. But back in the day, we used clear mascara to hold our brows thoughtfully in place. Today we have products that not only specifically are meant to hold the shape of the brow, but [are] waterproof to protect against sweat.” — Tonya Crooks

Milk Makeup Kush Fiber Brow Gel $20 Shop

We’re loving this one in particular right now.

5. The Mona Lisa Doesn’t Have Eyebrows

If you already knew this or never thought about it, we don't blame you either way. Just think of all the tourists taking pictures with the painting and never once realizing her famous face doesn’t include the feature we’ve come to love so dearly. But there was a report in 2007 that suggests either Leonardo da Vinci revised the painting (removing the brows) or that they had been unintentionally removed when the painting was cleaned.

6. Eyebrows Don't Actually Do Anything to Change Your Face or Eye Shape

“What they do is give people an impression of you. Are you happy? Sleepy? Mad? Surprised? Your eyebrows give a very quick first impression of the type of person someone thinks you are.” –Elke Von Freudenberg

7. Strong Brows Are Not Just a Passing Trend

“Brows are no longer considered a trend but an industry focus, becoming a major category in makeup. According to FCB Research, it is estimated that 50% of consumers will take care of their brows in their daily beauty routine versus 28% in 2015.” — Jared Bailey, Benefit Cosmetics global brow authority

8. Unibrows Were Seen as a Sign of Intelligence

Many cultures throughout history held the unibrow in very high esteem. While we’re more apt to pluck or tweeze, many notable figures exaggerated the hair because it was considered to portray intelligence and beauty.

9. Stress Affects the Growth of Your Eyebrows

“Stress can cause your brows to grow slower or not at all. I see brides trying to get their brows growing for the big day, and then once the honeymoon is over, their brows finally are growing in.” –Elke Von Freudenberg

10. Your Hair Follicle Attempts to Recover the Hair After You’ve Plucked It

“Does the skin around your eyebrow bump up right after you tweeze or wax? It’s usually the hair follicle closing to save the hair. It relaxes in about two hours and then it’s gone. It’s not a breakout. If you notice bumps two to three days after a tweeze or wax? That’s a breakout. That’s usually from a product that was applied right after the wax or tweeze.” –Elke Von Freudenberg

Click over for four sneaky tricks to faking thicker brows.