Emperor Penguins

Photograph courtesy Giuseppe Zibordi/Michael Van Woert/

Traditional parenting roles are reversed for emperor penguins, which live only on the harsh Antarctic ice. After a female penguin lays an egg during the winter breeding season, she promptly takes off to feed at sea. The job of keeping the precious egg warm falls squarely on the male's shoulders—or feet, to be exact.

Males stand and protect the egg by balancing them on their feet and covering them with feathered skin known as a brood pouch. During this two-month period, the males eat nothing and are at the mercy of the Antarctic elements. Once the chick is hatched, the male feeds it with milk from a gland in his esophagus. When the female returns with a bellyful of food to regurgitate for the chick, the male heads off for his own feeding session at sea.