Penguin Anatomy
Wings:
A penguins wings are called flippers. They're hard & rigid, and covered with small, stiff feathers that are not waterproof (unlike the rest of a penguin's feathers). Most birds have hollow wing bones, however, penguin wing bones are solid. Because of the density of their bones, penguins aren't very buoyant, which helps them dive.
A humboldt penguin's wings
Legs:
A penguin's legs are located as far back as possible on their body, so that they trail behind the penguin when it swims and are at the perfect place for steering. Even though you don't see them, penguins do have knees and upper legs; they're completely enclosed inside the penguin body. Because their legs are so short, its difficult for penguins to walk on land. Waddling seems to be the easiest way for them to get around.
Feet:
All penguins have three large toes with webs in between (webbed feet), and a small fourth toe at the back of the foot. Penguins also have blunt, heavy, nonretractable claws that they use for gripping the surface of slippery rocks, propelling themselves when they're sliding on the ice, etc.
Penguin feet are callused and tough for walking through snow and on rocks
Feathers/Skin:
A pengun's skin consists of two layers: a fat layer and a feather layer. The fat layer (also called blubber) helps keep the penguin warm, and is several centimeters thick.
The feather layer, which is the top layer, also helps keep the penguin warm, and consists of two parts: a downy part and a stiff part. Penguins have the greatest density of feathers on their body: up to 80 feathers per square inch. The tight coat of feathers on a penguins almost look like fur, giving it a sleek appearance. A penguin's feathers make a windproof outer shell that insulates the penguin and prevents cold water from reaching it's skin. The feathers also provide padding for the penguin.
The shape of a penguin's beak determines what it eats. King penguins,
like this one, use their pincerlike bill to catch squid and fish.
An African penguin skeleton
