Unit B: Interactions Among Living Things
1. Get Set to Explore
- adaptation: Any characteristic that helps an organism survive; adaptations can be physical, including body structures; they can be behavioral.
- biome: A large group of ecosystems that have similar characteristics.
- Go over the definition of biome. Show students pictures of the following biomes and let volunteers identify each one: desert, grassland, rainforest, swamp, tundra. As each biome is identified, ask the class to describe its unique features. If students are unfamiliar with the swamp ecosystem, define and describe it for students. For review of the other biomes, refer students to Student Edition Chapter 4.
- Review the definition of adaptation. Ask students to give examples of adaptations that different organisms have.
- Introduce the Discover! question: How do long ears help a jackrabbit to survive in a hot environment? Have students identify the adaptation that is the subject of the question. It is the jackrabbit's long ears. Encourage students to use the description in the question to try to identify the type of environment that the jackrabbit lives in. Students should choose between the grassland and the desert biome. Tell students that in the simulation, they will learn more about the adaptations jackrabbits and other animals have for life in specific biomes.
2. Guide the Exploration
- Instruct students to launch the Discover! Simulation and to listen carefully to the directions. They should make a chart that lists the five animals and gives space for writing predictions for each animal's biome, the actual biome each is adapted to, and at least one adaptation to the biome, perhaps by modifying the Three-Column Chart in this book. Direct students to record their predictions before continuing the simulation.
- Point out that students can learn about each animal and environment by clicking the pictures. They match an animal to a biome by dragging the picture of the animal next to the biome picture. Remind students to take notes on what they learn.
- Go over how all five of the animals are adapted to their biomes. Students should refer to their notes from the simulation during the discussion. Guide students to note the following adaptations: the jackrabbit's long ears help it stay cool in the hot summers of the grassland; the camel's fatty hump is used to provide water and energy when food and water are not available; the bat avoids getting overheated by hunting for insects at night; a caribou's foot pads help prevent it from sinking in the spongy tundra in summer, and by shrinking in the winter, these furred pads, along with the hard hooves, help the caribou securely grip hard, icy surfaces; the alligator prevents itself from becoming overheated by burying itself in mud.
- Discuss Step 3's Wrap-Up text with the class. Let students talk about the adaptations of each of the animals shown in the simulation.
- Have students work in pairs on the Extension questions. Encourage students to look for similarities in what the animals need to adapt to (climate, for instance) and differences in the ways that they adapt.
If time permits, present students with the following questions:
- Critical Thinking Analyze Reread Student Edition page A7 of your textbook. Based on what you have learned about alligators, do you think they could live in estuaries? Why or why not? Answer: Alligators are adapted to living in freshwater ecosystems. Estuaries have saltier water than swamps (where alligators thrive) do. Since alligators need to drink a lot of water, they probably would not thrive in places where the water is salty.
- Inquiry Skill Observe What kind of biome do you live in? To answer the question, make observations of the organisms native to your area. Another important clue is the climate of your region. Answer: Answers will vary, depending on your location. Most of the United States is part of one of the following biomes: forest, grassland, or desert.
4. Reaching All Learners
Ask interested students to choose a biome and make a diorama showing typical plants, animals, and landforms of that biome. Encourage students to do library research on their biome before designing their diorama. Challenge them to include at least five different plants and five different animals in the diorama. Let students describe the details of their diorama to the class and put the dioramas on display for students in all different classes.