If you’re like us, then you’ve probably read Phillip Pullman’s “His Dark Materials” series more than a few times. Much like Narnia, Earthsea and the world of Harry Potter, it’s worth making repeated journeys into Lyra Belacqua’s world(s). In fact, like us, you’re probably looking forward to the December film release of “The Golden Compass,” especially seeing the Panserbjørne, Iorek Byrnison. Come on, who wouldn’t want to see the renegade armored polar bear and would-be king come to life on the big screen?

Polar bears are amazing – and we’re not talking about fictional armored polar bears now. These incredibly huge, majestic animals live in some of the most extreme conditions on Earth. Imagine living in temperatures that can plunge as low as -50°F! Polar bears have evolved over time to withstand the bitter cold of the Arctic. Just by sight alone, you can see several adaptations. Most obvious is the polar bear’s color, which can range from a butter cream yellow to a very pure white. Appearing white like its surroundings provides a natural camouflage for the polar bear. But, interestingly, appearances can be deceiving. Polar bears aren’t actually that color – their skin is black.

Image © Keith Levit/Shutterstock

You know how it’s warmer for you to layer clothing on a cold day – well it’s the same for a polar bear. Two coats cover a polar bear’s black skin to insulate it from the cold. There’s a colorless, soft, fuzzy undercoat of fur, which rests against the skin. And on top of the undercoat, is a thick covering of long, stiff guard hairs, which also are colorless – like tiny, clear plastic straws. The fur only appears white because it reflects visible light, much like the snow and ice that surround the polar bear. The undercoat traps air next to the skin, while the guard hairs help to repel water. There’s another layer of protection that you can’t see. A thick layer of blubber ranging from one or two inches to four and a half inches sits just beneath the skin, covering all the bear’s muscles. Blubber is a layer of stored-up fat that acts as a blanket to hold in the bear's body heat. It can also be a source of stored up energy if the bear ever finds itself without an immediate food source.

Another adaptation that has helped the polar bear survive the cold is the size of its ears and tail. If you’re wondering how that works – it’s pretty simple. A bigger tail and ears would mean more surface area, which means a larger area susceptible to heat loss. Small ears and a small tail reduces the surface area, thereby minimizing the heat loss. OK, so you’re probably thinking with that reasoning, then a polar bear should have some pretty small paws. Not so. And that’s because the benefits of big paws considerably outweigh the heat loss thing.

Image © Keith Levit/Shutterstock Mother with Polar Bear Cub at Churchill Manitoba

Large paws, measuring up to one foot across, support and help distribute the polar bear’s impressive heft across the ice. Its black footpads are dotted in tiny bumps called papillae. The papillae along with thick tufts of fur, which surround the bear’s toes and footpads, and short, strong claws give much needed traction. As you can see, a polar bear’s paws are essentially snow shoes! Try walking on ice all day, every day without a pair. And, it turns out the paws are a bit like a pair of cross trainers, too – but instead of switching from basketball to running in a split second, they go from snowshoe to a paddle and rudder for swimming.