How do penguins adapt to all kinds of weather?

Penguins have a thick layer of feathers on their bodies, which are waterproof and cold-proof. Beneath the skin is a thick layer of fat. In order to make feathers more waterproof, penguins can secrete a special oil. When the weather is hot, the blood vessels in the fat layer can expand, bringing the heat in the body to the skin surface and exciting it.