Penguins’ bodies are their survival kit

In addition to their skeletons, penguins have evolved many other adaptations to life in a cold climate:

• They have a very streamlined body for efficient movement in water.
• They have very dense, flat feathers—up to 80 per square inch of skin—to provide waterproofing and insulation.
• They have an extremely thick layer of fat under the skin, which also helps conserve body heat.
• Their veins and arteries lie very close together, enclosed in fatty tissue under thick scales on the legs and feet. This also reduces heat loss.
• They have powerful legs and breast muscles for speedy swimming. Their legs, short but strong, produce a waddle which is actually more efficient than human walking. (In soft snow, some penguins can outrun people!)
• Their tongues and mouths have raspy structures for gripping fish, squid and tiny, shrimp-like creatures called krill.

Penguins’ history is mostly mystery

Scientists have discovered relatively few penguin fossils. As seabirds, penguins spend a lot of their time in the water or on remote islands, neither of which are good places for fossilization.

The largest penguin ever was an extinct species which stood up to 6 feet tall (1.8 m) and could weigh about 250 pounds (110 kg)—the size of a large man!

The earliest penguin fossils date back to roughly 40-60 million years. Their wing structure indicates penguins evolved from flying birds. Penguins’ closest living relatives are the albatrosses and petrels.

A penguin by any other name…

European sailors and fishermen first applied the word “penguin” to the Great Auk, a now-extinct seabird which once inhabited the North Atlantic. In 1588, European explorers at the tip of South America discovered another bird with similar appearance, and called it a penguin, too.

No one knows exactly where the word “penguin” comes from. The most common explanation holds that it combines two Welsh words: pen, meaning “head,” and gwyn, meaning “white.” (The auk had a large white spot on its head, as do some species of penguin.)

more