
Not many hair follicles are as troublesome as a synophrys, the technical term for a unibrow—hair in the center of the forehead that gives the illusion of one single, unified, serious-looking eyebrow.
If you’re not familiar with how a unibrow appears, check out Exhibit A: the Muppet with a unibrow:

What exactly is a unibrow?
A unibrow is caused by specific genes in your DNA. A 2016 study published in Nature Communications examined over 6,000 subjects and found particular genes linked to traits like hair density, greying, curling, and unibrow fusion. Men, in particular, were more likely to have this trait, which is connected to the PAX3 gene.
The researchers speculated that once these genetic features are identified, the cosmetics industry could develop a product to influence or alter them. In other words, if you aren't a fan of your unibrow, science may soon offer a way to change it.
How to remove a unibrow
For now, the simplest method for eliminating a unibrow is plucking the middle hairs with tweezers. Be sure to pull them out carefully and use a moisturizer afterward to calm the skin. Special creams can also remove hair, but be cautious around your eyes and watch for any skin irritation. Shaving and waxing are also effective, though you'll need to keep up with maintenance as hair grows back. Laser hair removal may offer longer-lasting results for your unibrow.
Not everyone with a unibrow dislikes it. While unibrows aren't a common trend in the United States, in Tajikistan, a country in Asia, they are seen as a symbol of beauty. Women who don’t have the PAX3 gene use a green herb known as usma to create the illusion of a full brow. Could this be Bert's secret? The answer may remain a mystery.