SWIMMING BIRDS OF THE ANTARCTIC
Penguin ancestors could fly as well as any other sea bird. Now its wings are
short, paddle-like flippers that are entirely useless for flight. The bird has lived for
ages in or near the Antarctic regions, where it has few enemies. Thus it came to
spend all of its time on land or in the water. For generations it did not fly. In the
course of evolution, its wings became small and stiff and lost their long feathers. The
penguins, however, became master swimmers and divers. Of all birds, they are the
most fully adapted to water. Their thick coat of feathers provides a smooth surface
that is impenetrable to water. Their streamlined bodies glide through the water easily.
The birds use their wings as swimmers use their arms in a
crawl stroke, and they steer with their feet. Penguins can
swim at speeds of more than 25 miles per hour.
When they want to leave the water, they can leap
as much as 6 feet from the water's surface onto a
rock or iceberg.
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