May 1, 2019
Penguins cope well in the cold — some breed in the coldest conditions in the world. Their short outer feathers overlap, like tiles on a roof, to form a thick waterproof layer, and underneath are fluffier feathers for warmth.
Like seals and whales, a thick layer of fat under the skin provides insulation (and extra reserves for when food is scarce).
As a rule, the larger the penguin, the easier it is to conserve heat. In fact, many penguins are so good at keeping warm that they have a problem with overheating during the summer months.