The polar bear's footpads have a kind of “non-slip” surface, allowing them to get traction on slippery ice. Polar bears have strong legs and large, flattened feet with some webbing between their toes, which helps with swimming and walking on ice.

REMARKABLY WELL ADAPTED The bear's skin is black, which absorbs the heat that is channelled inwards by the strands of white fur, and the it has stubby ears that reduce its heat loss. Lastly, the polar bear has wide paws that spread like snow shows and stop it sinking too deep into the snow.

The largest polar bear on record, reportedly weighing 1,002 kg (2,209 lb), was a male shot at Kotzebue Sound in northwestern Alaska in 1960. Compared with the brown bear, this species has a more slender build, with a narrower, flatter and smaller skull, a longer neck, and a lower shoulder hump.

The polar bear has a monogastric digestive system with a simple and relatively short intestine typical of a carnivorous animal, and with the caecum completely lacking [22].