Is a Polar Bears fur white all year round?
In actual fact, polar bears have transparent fur over black skin. Reflection of the sunlight from the densely packed transparent hairs makes polar bears seem to be white. The bears’ black skin absorbs heat from the sun. The transparent fur is made up of hollow hairs called guard hairs. These air-filled guard hairs help transmit heat from the sunlight to the polar bear’s black skin as a solar heat collector. In turn, the reflection stops the heat being lost from their black skin. So – as long as they are in white snow, their fur is white. Were they to be taken to another environment, then their fur would take on the hues of that environment.
