Penguins are countershaded in color, meaning that their backs are dark and their undersides are light. This acts as a camouflage for them when they are in the water hunting for food. They have webbed feet, short legs and wedge-shaped tails. Penguins use their bills to catch food underwater. Penguins, like all birds, have feathers.
Penguins lose their feathers in a process called molting.
Their old feathers will not fall out until the new ones are completely in place. Penguins lay eggs and sit on them in nests. The average lifespan of a penguin is 15-20 years. The largest penguin grows to about 3.7 feet, weighing 60-90 lbs. The smallest grows to about 16 inches and weighs 2.21 lbs.