human
Why is it that a polar bear can live in the Arctic and a penguin can live in the Antarctic?
assistant
Polar bears are adapted to living in cold temperatures. They have thick fur, a layer of fat under their skin, and they have a special layer of blood vessels in their ears which helps them conserve heat. Penguins live in the Antarctic because the water there is very cold. The water freezes at about -2°C, so penguins need to be able to swim in order to find food.