To catch and prevent sweat from entering our eyes.

To give the face expression?

More primitive animals can't use body language as effectively as us since they don't have them? Maybe that's why we're ahead. More unclear communication among the lower species.

They're for when humans are on the run from the law and need a quick disguise. Pluck out all your eyebrows, and arrange them as a moustache on your face, using hotel shampoo to stick them in place.

To pluck them all out and then pencil them back in.

To aid in expressing emotions.. You've seen women who draw angry eyebrows on themselves what's up with that 😁

To aid in expressing emotions.. You've seen women who draw angry eyebrows on themselves what's up with that 😁

To aid in expressing emotions.. You've seen women who draw angry eyebrows on themselves what's up with that 😁

To aid in expressing emotions.. You've seen women who draw angry eyebrows on themselves what's up with that 😁

To aid in expressing emotions.. You've seen women who draw angry eyebrows on themselves what's up with that 😁

To aid in expressing emotions.. You've seen women who draw angry eyebrows on themselves what's up with that 😁

So you'd have something to pluck daily

It plays a massive part in how we recognise faces: https://www.youtube.com/watch?v=RA9nUUEuPJ8&ab_channel=AsapSCIENCE (you only need to watch the first minute if you're busy).

Protect the ehe and also help giving expression to your face

Probably to keep stuff out of your eyes, also to arouse me