Why Do Polar Bears Have White Fur

So why then do polar bears look white.

Why do polar bears have white fur. Polar bears appear whitest in the direct sun as the brighter the light the more reflective and luminescent their coat. Polar bears are protected with 10 cm thick hide and dense fur which prevent the animal from getting cold. In addition to rugged webbed paws for swimming in freezing water and sharp almost carnivorous teeth ideal for ripping up seal the king of the arctic has one lesser known but equally important trait that has helped it to survive in frozen wilderness of the arctic circle. In fact a polar bear s skin is black and its hairs are hollow.

Polar bears are white but their hair is mostly clear. This is particularly helpful when the temperature dips below 30 f in the arctic. Polar bears skin is black and their fur is clear and transparent. Interestingly the polar bear s coat has no white pigment.

The reflection indeed gives rise to white color. Uv light also gets transmitted along the. It is mainly because of reflection. To recap when light shines on the polar bear s mostly clear guard hair some light gets trapped in the hair and bounces around creating luminescence.

Although it is most commonly believed that polar bears have adopted white fur as a way of remaining hidden from their prey this is but a helpful side affect of the original reason for the polar bears white colouring. This light scattering gives off more white coloured light due to luminescence. Polar bear hair shafts are actually hollow which allows the fur to reflect back the light of the sun. Each shaft of hair is pigment free and transparent and has a hollow core which reflects visible light.

The clear guard hairs have a hollow core that traps and reflects white light from the sun. Polar bears keep warm because they have a thick layer of fat. While the hair is transparent it reflects the white light from the sun making the polar bears appear white in a similar way to snow and ice. It s a matter of optics.

Much like ice this reflection is what allows these bears to appear white or even yellow at times. Why do polar bears have white fur. The polar bear has evolved over time from the common brown bear by changing its fur colour to white the ideal colour to blend in with its ice covered surroundings. They have a thick layer of body fat which keeps them warm while swimming and a double layered coat that insulates them from the cold arctic air.

Polar bears have white fur so that they can camouflage into their environment. It s also thought that the transparency of their thick coats is designed to allow better heat absorption from the sun into their black skin beneath. When it hits a light scattering particle on the inside or salt on the outside the light breaks up even more and gets sent in all different directions. Polar bear fur consists of a dense insulating undercoat which is topped by guard hairs of various lengths.

That is why polar bears remain white all throughout the year. If you ve ever seen a polar bear outside the. The light energy bounces around inside the hollow hair causing a reaction called luminescence. The bear s furs are hollow and transparent as a result of which they reflect sunlight from the snow.