Adaptations: Polar and tundra climates

In the Canadian North, close to the North Pole, the winters are long, dark and cold and the summers are short and cool. This is a polar region, covered mostly by snow and ice all year. It's a very tough climate to live in! The land that is close to the ice-covered areas is called tundra. It’s not always snowy here, but the ground is permanently frozen, so not much can grow.

As a result of this unique environment, animals in polar regions have adapted to the conditions. Due to the severely cold temperatures and snow cover, animals of the tundra tend to have thick layers of feathers or fur. These act as insulation, trapping heat close to the body. Many of them have large bodies and short legs and tails to minimise heat loss. Take for example, the arctic fox.

Compared to a fox found in warmer regions, arctic foxes have much smaller legs, snouts, and ears. Their coat is thick and highly insulating. Arctic fox feet are also padded with thick fur. This keeps the fox warm, and allows it to move quickly and quietly over the snow. An arctic fox may also look different depending on the time of year!

In winter, its coat is white, allowing it to blend into the snowy and icy surroundings. But in spring and summer, the coat changes to brown or grey. This provides better camouflage against rocks and dirt once the snow has melted away. Snowshoe hares and ermines are other examples of tundra animals that change their coats in order to blend in with the changing environment. Some of the animals of the tundra, like bears and marmots, enter into a long period of sleep during the winter to conserve energy.

They hibernate for anywhere from four to eight months. In hibernation, breathing and heart rates slow and body temperatures drop. All of these things happen so the animal can use less energy. But not all animals hibernate. Some, like lemmings, stay active all winter.

They do so by burrowing, and creating tunnel networks under the insulating snow. Meanwhile, many of the insects of the tundra will spend their entire life buried in the soil. The arctic woolly bear caterpillar spends around 90% of its life completely frozen, thawing out only for a short period every summer. Because the summer in the arctic is very short, the larval stage of arctic insects tends to be much longer and their adulthood tends to be shorter than those of insects in warmer climates. It takes 7 years for the arctic woolly bear caterpillar to build up enough resources to pupate into an adult moth.

When it comes to polar marine animals such as whales and seals, the body is isolated by a layer of fat below the skin called blubber. This blubber layer restricts heat loss in both cold air and cold water. Polar bears are another animal with blubber. Underneath their fur, polar bears have black skin which absorbs the heat of the sun, and below the skin is a layer of blubber. The blubber is particularly helpful while polar bears swim, keeping them warm in the cold water and helping them float.

Thick layers of fat and fur for warmth… A heat-efficient body shape that minimises heat loss… A white appearance to camouflage in the snow… Hibernation… Using snow as insulation… And a slow growth and reproduction cycle are some of the ways that animals have adapted to living in polar and tundra climates.