Is it true that polar bears are actually black?
No, they are definitely white. It is true that polar bear skin is black, but as we all know it’s covered by a thick coat of white fur, so the bear as a whole is white.
The colour of a thing is how it appears to your eyes. Think of it like this: if you paint your bedroom walls white, are they ‘really’ still brick coloured? Taken individually, polar bear hairs are actually transparent.
The coat appears white for the same reason clouds do: all the tiny reflections from the myriad jumbled surfaces combine to reflect the light back to your eyes. It used to be thought that each hair acted as an optical fibre to funnel sunlight down to the skin, but recent studies have ruled this out and the white colour is purely for camouflage.
Answered by Luis Villazon