Complete Polar Bear Facts

The Big Guess

Polar bear hair is not a hollow tube
For many years people thought that polar bear hair was very high-tech, but it's actually pretty simple and the scientists just made a really silly mistake.

Polar bear hair is clear, not white; it just reflects sunlight and appears white - snow is like that too. In the early 1980's someone suggested that polar bear hair was a hollow tube, like a drinking straw. They guessed that heat from the sun would hit the polar bear, and go down the hollow part of the tube, and touch the bear's skin. Polar bear skin is actually black, and black is a colour that absorbs heat. The scientist thought he had discovered a special way that polar bears keep warm in a very cold part of the world, but it was just a Big Guess. The scientist never checked to see if his Big Guess was right.

Other scientists heard about his Big Guess, and thought it was true. Suddenly people were writing about sunlight going down the hollow part of polar bear hair just like a fiber optic line.

A fiber optic is a thin clear bendable thread, that light can move though. It sounds very much like a thin clear hollow polar bear hair. The Big Guess made sense to lots of people. But they made one silly mistake.

No sunlight in winter
Everyone knows polar bears live way up north. In the far north, there is no sunlight in the winter. The summers have sunlight all the time, and the winters have darkness all the time. Polar bears can't use sun to keep them warm in winter when there is no sun!

That's when someone tested the scientist's Big Guess and found that polar bear hair isn't hollow like a tube and light won't move through it. The Big Guess was actually a Big Mistake! For a more scientific view of the issue, please see Daniel Koon's Page on the subject. It is well referenced.