The Arctic Ocean and the Southern Ocean are at the top and bottom of the world. The water there is very, very cold. But many animals live there.
Penguins, whales, and walruses all call these cold places home. How can they survive?
All of these animals make their own heat. Their bodies turn the food they eat into heat. Your body does the same thing!
But these animals have a problem. Their bodies lose heat all the time. How can they stay warm?
The answer is insulation. These animals’ bodies have a thick layer of fat called blubber. Blubber helps hold in heat. It keeps the animals warm, even in the cold water.
What about animals like snakes, turtles, and fish? Their bodies don’t make their own heat. They need the environment to keep them warm.
Most of these animals don’t live in the Arctic or Antarctic. They can’t stay warm in these cold places. But some fish do live in the cold oceans.

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