The desert tortoise lives in the Mojave Desert in southern California. Summer days there can be hotter than 110 degrees, and winter nights can drop below freezing. A tortoise cannot sweat or shiver to stay comfortable. So it digs.

With its strong, flat front legs, a tortoise digs a burrow, a tunnel under the ground. Deep inside, the soil stays cool in summer and does not freeze in winter. A tortoise spends most of its life in its burrow. It comes out mainly in spring, when there are fresh plants to eat.

Rain is rare in the desert, so a tortoise must make the most of every storm. After a rain, it drinks from puddles and can store water inside its body for months. Some tortoises even scrape small dips in the dirt that catch rainwater.

Other animals use tortoise burrows, too. Lizards, snakes and even burrowing owls hide in them to escape the heat. That is one reason scientists say that protecting the tortoise helps protect many desert animals.