Granted, sometimes we are naturally expressionless, like when your 10 year old boy comes home from school and decides to vaccuum his room...
Exactly. Or if we want to look like David Bowie.
But you can't be expressionless in every single situation! Even at rest, eyebrows give you a little something. A nuance, if you will.
If your husband decides to give you flowers out of the blue, you might lift your eyebrows in mild surprize.
Sometimes you may need to show concern, or sympathy. Like if your BFFF breaks her rubber ducky. Awww....
Obviously, eyebrows are essential to show that you're angry about something. Otherwise how would your 16 year old daughter understand your reaction to her not calling from the 'party' at midnight when she was supposed to?
And these kind of eyebrows would efficiently communicate to the hospital ER staff that you're extremely worried about this odd freckle you've just discovered in your bellybutton.
Hypochondriacs rely on eyebrows just like this!
If you're at all uncertain or doubtful about the usefulness of eyebrows, an expression such as this would probably be on your face. But only, I repeat: ONLY if you have eyebrows.
Without eyebrows? Nothing.
Some eyebrows are better than none. This Marlene Dietrich pluck is a fashion statement, but at least there's a little expression there, even if it is somewhat superior and aloof - it still counts!
And Frida Kahlo....
Well, she just WINS at eyebrows.
You can make someone else smile by sharing.