Penguins are birds, but unlike most birds, they cannot fly. They are one of about 40 species of flightless birds. Most penguins live in the Southern Hemisphere. No penguins live in the North Pole.
They are very social and live in colonies. They are great swimmers who use their wings like paddles to swim through the water. They can stay underwater for 10-15 minutes before coming to the surface to breathe. They cannot breathe under water.
Their feet are small so they don't lose too much heat as they stand on the ice. They help each other stay warm by gathering together and shuffling around. Their main diet is fish and krill. They will swallow pebbles as well as their food. It is believed that the stones may help grind up and digest their food.
They can drink seawater because they have a special gland that filters salt from the bloodstream.
Their colors help them to be camouflaged while swimming. From above, their black backs blend into the dark ocean, and from below, their white bellies match the bright surface. This helps them avoid predators.
Once a year, penguins molt. Most birds will lose a few feathers at a time throughout the year, but penguins lose all their feathers at once. They cannot swim without feathers, so they eat a lot more before they molt to survive the 2-3 weeks it takes for their feathers to grow back.
