Cold adaptation

Penguin with ice beaded on it's back after a snowstorm. Image - B Karl

Adélie penguins live further south than any other penguin species and have to cope with extremely cold conditions.

Adélies have short stocky bodies and small extremities. This reduces the body's surface area and the amount of heat that can be lost.
Adélie feathers are short, densely packed and overlapping, like tiles on a roof. Along with oil from a preen gland near the tail, these provide a totally waterproof layer.
Underneath the feathers there is also a layer of warm down close to the skin.
A thick layer of fat under the skin provides additional insulation from the cold − an adaptation common among warm-blooded, Antarctic vertebrates.