31 Life in the Desert

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Life in the Desert by Sheila Black Table of Contents Introduction page 2 Chapter 1 Desert Plants page 6 Chapter 2 Desert Animals page 8 Chapter 3 people in the Desert page 12 Conclusion page 14 Glossary/ Index page 15 Comprehension Check page 16

Introduction Deserts cover one-seventh of Earth. They can be sandy or rocky. They are very hot and dry. Some deserts are formed, or made, by wind. The wind blows warm air that makes the land very dry. Other deserts form because of tall mountains. It only rains on one side of the mountain, and the other side gets dry. This is part of the Sonoran Desert. All of the deserts in the United States are in the Southwest or West. This lake covers desert land in Arizona and Utah. It was created by the Glen Canyon Dam. Deserts are mainly dry. But rivers and streams flow through parts of the desert. Some deserts also have lakes. These lakes form when people build dams. A dam stops the flow of a river and creates a lake. Desert rocks are made of different kinds of minerals. Some rocks are very colorful. Desert soil, or dirt, is made mostly of sand, gravel, and clay. minerals: hard materials like gold and iron that are formed naturally in the ground

Dry streams fill with water when it rains. There is very little rainfall in the desert. It only rains a few months of the year. The ground is hot and dry. When it rains, it rains a lot. The water moves fast. A dry area can be flooded in minutes. Sometimes it snows high in the mountains. When the snow melts, it flows down into the desert. Plants and animals that live in the desert need the water from snow. Without it, they could not survive during the hot, dry times when no rain falls. The plants and animals have survived by adapting to the severe weather. severe: harsh; very bad The La Sal Mountains in the state of Utah are surrounded by desert. It's a Mirage If you travel in the desert on a hot day, you might think you see a pool of water in the distance. But when you get to that place, you find that the water is not there. This is called a mirage. Light rays from the sun bend in the air before they hit the ground. This makes the mirage.

CHAPTER 1 Desert Plants Water evaporates quickly in the desert. Plants need water to live. How do desert plants survive with so little water? Cactus plants grow all over the desert. When it rains, their underground roots take in a lot of water. Their big stems, or bodies, can hold the water for a long time. The cactus plants have thick skin. The skin is covered in a kind of wax. It helps keep water inside the cactus. A saguaro cactus can take in a ton of water in a single day. A ton is 2,000 pounds! Seeds Desert plants make seeds. Some seeds have hard coats. When it rains, the water bounces the seeds over the rocky ground. The seed coats break. The seeds sprout and grow into plants. This is a mesquite plant. Other desert plants have long roots. The roots help them absorb water. The roots of the mesquite plant are over 100-feet long. Some desert plants survive by losing their leaves in the summer. These plants rest during the hot summer. The winter rains restore, or bring back, their energy and they wake up again. The ocotillo is one of these plants. In summer, it looks dead. But when it rains, its tiny leaves and pretty orange flowers begin to grow. Language DETECTIVE Clue: Leaves is a multiple meaning word. Can you find another multiple meaning word on this page? The ocotillo plant is sometimes called candlewood.

CHAPTER 2 Desert Animals Animals need water, too. Desert frogs and toads lay their eggs in pools of rainwater. The eggs hatch and the baby frogs quickly grow into adults. Soon the hot sun dries the earth. The adult toads and frogs survive by going underground. They stay in the ground for a year or more. They rest and wait for the rain. A desert frog grows quickly and then rests for a long time. A kangaroo rat stores water in its body. The kangaroo rat also saves water. It builds an underground home called a burrow. When the rat breathes, it gives off water. This water stays inside the burrow. Pack rats store seeds and nuts in their burrows. The seeds and nuts have absorbed water from the air. The pack rats get water by eating the seeds and nuts. Pack rats will chew on cacti if they are suffering from thirst. Many birds live in the desert. Some desert birds get their water by eating bugs, lizards, and other small animals. This is a pack rat. The Gambel quail digs up seeds from the ground. It gets water from seeds.