In contrast to some of the large whales, dolphins and porpoises have teeth, which they The blowhole is opened during their frequent trips to the surface to breathe. Like other whales, dolphins have lungs and breathe through a single nostril, called the blowhole, located on top of the head. The mothers provide milk for the young for a year or more.

When penguins desire to get out of the water, ………ĭolphins and porpoises, often called simply «small whales,» are mammals, not fish, and are thus warm-blooded, keeping their body temperature nearly constantĮven when they are exposed to different environmental temperatures. 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. Penguins can swim at speeds of more than 25 miles per hour. The birds use their wings as swimmers use their arms in a crawl stroke, and they steer with their feet. Their streamlined bodies glide through the water easily. Their thick coat of feathers provides a smooth surface that is impenetrable to water. Of all birds, they are the most fully adapted to water. The penguins, however, became master swimmers and divers. In theĬourse of evolution, its wings became small and stiff and lost their long feathers. Thus it came to spend all of its time on land or in the water. The bird has lived forĪges in or near the Antarctic regions, where it has few enemies. Now its wings are short, paddle-like flippers that are entirely useless for flight.

Penguin ancestors could fly as well as any other sea bird.

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