Why some mammals can have 2 or more hair colors while humans only one?

That's not true! My husband has light brown hair, blonde eyelashes and a red beard!

Why some mammals can have 2 or more hair colors while humans only one?

Hi! I'm a hairdresser and it does happen that some of my young clients have 2 hair colors. I've seen some boys have dark blond hair with darker patches here and there. This usually changes as they get older and gets even colored!!

Why some mammals can have 2 or more hair colors while humans only one?

Because that's done for camouflage.

Some animals naturally evolve with camouflage if it's beneficial their survival.

We don't need it as we're predators so we're more likely to have single coloured hair.