In this science lesson, students will learn about the climate of deserts, plants and animals that are adapted to live in deserts, and names and locations of the world’s major deserts.
Objectives
* Students will know the definition of desert.
* Students will know some of the adaptations that allow plants and animals to live in the desert.
* Students will be able to list at least 5 of the world’s major deserts.
Climate of the Desert Biome
Deserts are defined as very dry areas that receive 25 cm (10 inches) or less of rain per year. People tend to think of deserts as being hot as well as dry, but not all deserts are hot year-round. Some deserts located in the middle of continents or in rain shadows such as the Great Basin Desert, the Gobi Desert and the Patagonian Desert, have freezing temperatures in the winter.
Plants of the Desert Biome
Plants of the desert have many adaptations to help them survive with little water.
* Shallow root systems allow plants to absorb rainwater from the soil’s surface.
* Succulent plants such as cactus store water in their thick stems, and have waxy skin to keep moisture inside
* Spines and thorns protect plants from being eaten by animals and birds
* Annual plants are dormant during most of the year, and have a very short life cycle. They germinate rapidly after seasonal rains, then bloom and go to seed within a short time.
Desert plants include Joshua tree, saguaro cactus, creosote bush, yucca and prickly pear.
Animals also have many adaptations to allow them to live in the desert.
* Many desert animals are nocturnal, asleep during the day and active at night
* Living in underground burrows allows animals to escape from the heat
* Some animals are able to go for long periods of time without drinking by storing water in their bodies
* Large ears, such as those of the jackrabbit and mule deer, help to cool the animal’s blood by allowing heat to radiate from vessels near the surface
* Light colored coats reflect heat
Desert animals include tortoises, lizards, snakes, rabbits, mice, bats, owls, kangaroo rats, foxes and coyotes.
The World’s Major Deserts
Point out the locations of these major deserts on a map:
Sahara Desert- Northern Africa
Great Sandy, Gibson, Great Victoria, and Simpson Deserts- Australia
Arabian Desert- Arabian Peninsula
Karakum Desert- Turkmenistan
Gobi Desert- China and Mongolia
Chihuahuan, Great Basin, Mojave, and Sonoran Deserts – North America
Thar Desert- India and Pakistan
Kalahari Desert- Southern Africa
Review Questions
1. What is the definition of a desert?
2. Are deserts always hot?
3. What are some adaptations of plants that live in the desert?
4. What are some adaptations of animals that live in the desert?
5. List 5 of the world’s largest deserts and their locations.
