Why do the male emperor penguins carry egg?

Emperor penguins are unique among birds in that the males are responsible for incubating the eggs. The females lay the eggs and then leave the colony to feed at sea, leaving the males to keep the eggs warm for approximately two months until they hatch. The males huddle together in groups to conserve heat and take turns incubating the eggs on their feet, balancing them on top of their webbed feet and covering them with a protective fold of skin.