Designed to Swim

on January 1, 2015

No matter how many hours you stare up at the clouds, you’ll never see a formation of penguins flying overhead. They use their wings for another purpose. Their uniquely designed feathers, bones, and muscles enable them to “fly” through the cold waters of the Southern Ocean.


Macaroni Penguin, Galápagos Penguin and Gentoo Penguin

Emperor Penguin

Emperor Penguin: Did you know that they can grow as tall as 4 feet (1.2 m)?

  • Waterproof Feathers

    The feathers on penguins are woven into a dense, overlapping coat that is unique among birds. (As many as two hundred feathers are packed into every square inch!) A warm layer of air between these overlapping feathers and the penguins’ skin helps insulate them from the cold water and wind.

  • Stiff Paddles

    Unlike other birds, penguins have wings that are fused into stiff paddles that can easily maneuver through water, which is almost 900 times denser than air. They can dart up to 9 miles per hour (14.4km/h)!

  • Strong Muscles

    Penguins have the strongest wing muscles of any bird. In fact, one swipe from an emperor penguin’s wing can break a human leg! Their powerful muscles are needed to propel them through the water.

  • Torpedo Body Shape

    Penguins’ unique body shape contributes to their fuel efficiency. A layer of blubber not only keeps out the cold but converts them into fast–moving torpedoes underwater.

Related Downloads

Underwater Flight

PDF Download

Designed Not to Fly

This issue shares some of the amazing designs of flightless birds.

Browse Kids Issue