The arctic is very cold and there are limited sources of food. There are no trees and short growing seasons for living things. The ocean supports animal life.

The desert in North America is dry and hot. Most plants grow low to the ground. Deserts have limited precipitation.

Polar bears live in the arctic. They have blubber under their skin and a thick coat of white fur to keep them warm. Their white fur also gives them camouflage in the snow. Polar bears have large paws to help them walk on the snow, sharp teeth and claws to catch and eat other animals, and small ears to minimize heat loss.

Gila monsters live in the desert. They use their claws to burrow in the ground and escapethe heat. Their spotted coloration provides camouflage. Gila monsters can eat infrequently because they store fat in their tail. They use their tongue to detect prey and gather information about their environment. Also, gila monsters can inject venom through their teeth.