why do other animals have eyebrows?

for humans it serves an evolutionary purpose, people ran on the 
savannah for long periods and it made sweat not go into the eyes.

but dogs have eyebrows and cats too.. mammals.. yes most mammals. 
right not all animals, mammals mostly.. lizards or reptiles etc 
dont have eyebrows.

it adds a lot of personality and social cues, very important. so 
eyebrows are needed for intelligent creatures.

aliens will have eyebrows, the whole non-eyebrow bug eyed alien 
model is FLAWED!