Why do Polar Bears have white fur?
Polar bears do not have white fur, but semi-transparent fur. The polar bear’s fur seems colourless and for many years, scientists worked on the theory that the individual hairs act as fiber optics bringing sunlight directly to the skin. This has recently been proven to be incorrect, and the hairs are not truly transparent, but contain keratin. Viewed side-on, the hairs appear colourless; viewed lengthwise (as if one was looking down a telescope) the hairs no longer appear transparent.
