When looking at a polar bear, the first thing you may notice is their size or their thick white fur. Most people would find it absurd to say that the fur color would be anything except white. In truth, that fur you are seeing is actually clear! Much like snow, the fur just reflects the sunlight and looks white.
Since each hair on a polar bears body is made out of keratin, it absorbs ultraviolet light from the sun. What the keratin does is provide extra warmth for the skin. On further note, polar bear fur is water repellant, and the hair does not mat when it is wet. This helps the polar bear shake off water and ice, providing it with even more warmth.
Someone had the notion that the polar bear hairs might be much like optical fibers. This notion was wrong, though. In the early 1980's, a scientist figured that polar bear fur was like a hollow tube, which the heat of the sun would hit, and go down the tube, touching the skin. He concluded that a polar bears skin is actually black, which is a color that absorbs heat. He thought he had figured out how the polar bear kept warm in very arctic places, and was sure that their fur was transparent.
That scientist was absolutely correct. On very sunny day, the fur traps infrared heat and keeps the bear at a temperature of 98 degrees Fahrenheit(when the animal is at rest). The black skin is an adaption that allows for the maximum warming to the skin when exposed to sunlight. So despite the icebergs, harsh winds, and cold snow, freezing is not an issue for polar bears!
It was also discovered that many polar bears found in various zoos all over the continent were starting to turn a shade of green! Scientists found out that algae was the problem. The thing is, the algae was not on the outside of the polar bear hair, but on the inside! The reason for this supposedly came from pond water that surrounded the bears'.
So apart from having thick transparent fur, the polar bear is also one of the largest bears on Earth! Their weight is as close to 750-1,500 pounds. At a glance these bears may only seem like intimidating yet simple artic inhabitants, but there are defiantly many interesting and amazing facts about them.