Polar regions are often dark with freezing winds, and they receive little rain. Only the toughest can survive in such unwelcoming conditions. Polar animals have developed various mechanisms to protect themselves from the harsh climate. Penguins, for instance, huddle together to stay warm. The ones on the outside of the huddle aren’t so well protected from the cold, so they take turns standing in the middle. A lot of animals have got thick coats or long feathers, like the snowy owl, whose feathers are long enough to cover its legs. Larger animals lose heat more slowly than smaller ones, so many Arctic animals are quite big. A male polar bear can weigh up to 800 kilos.

It’s not only animals that need to wrap up warm  — plants do too. They have a lot of tiny overlapping leaves that completely cover the short stem. Plants can also stop growing if it’s too cold and start growing again when the weather becomes better.