- Clear communication is an essential part of doing science. It enables scientists to inform others about their work, expose their ideas to criticism by other scientists, and stay informed about scientific discoveries around the world.
- For any particular environment, some kinds of plants and animals survive well, some survive less well, and some cannot survive at all.
- Over the whole earth, organisms are growing, dying, and decaying, and new organisms are being produced by the old ones.
The Earth's biomes
A biome is a habitat with similar climate and vegetation. The Earth is separated into terrestrial and aquatic biomes.
The terrestrial biomes include the tundra, taiga, deciduous forest, grassland, desert and tropical rainforest.
Tundra: The tundra has extremely cold temperatures. Because of this, there is a very short growing season. There are very few trees. Vegetation such as mosses and grasses grow here. Animals such as reindeer, caribou and wolves are found here.
Taiga: The taiga is also cold, but not as cold as the tundra so the growing season is longer. Pines, firs, and spruce grow here. Moose, wolves, bears, deer, birds, and insects live here.
Temperate Deciduous Forest: Here the summers are hot and the winters are cold. Some trees that grow here include oak, chestnut and birch. Animals that live in this biome include deer, squirrel, chipmunks, and birds.
Grasslands : The grasses are the dominant form of vegetation in this biome because of the small quantity of rainfall. In North America, the animals that live here include coyotes and rattlesnakes. In Africa, animals such as zebras and giraffes live here.
Deserts : This biome is so dry that grasses are unable to grow. Plants and animals in the desert have special adaptations that allow them to live in especially dry areas. Some animals that live in this area include snakes, lizards and spiders.
Tropical Rainforests: The temperature in this biome is constant and so is the rainfall. There are a wide variety of plants and animal species that live in this area.
The aquatic biomes are separated into two types: Marine and Freshwater.
Marine Biome (i.e., Saltwater Biome): This biome covers more than 70% of the Earth's surface. There are a great variety of plant and animal life living in the oceans.
Freshwater Biomes: Freshwater biomes are divided into two categories: running water (streams) and standing water (lakes, ponds, swamps, bogs). A variety of organisms live in this biome including algae, snails, and crayfish. Raccooms, birds, and other organisms live along the banks.
- Show students different pictures of the Earth's biomes (these can be found at http://mbgnet.net/). Ask: What do you think it would be like to live in each biome?
- Ask students: What questions do you have about the different biomes? Students might ask:
Compile a list of students' questions - place these on the board.
Why should my students ask and answer questions in science?
How can I help my students ask and answer questions in science?
Place students into groups of three. Have each group pick one of the following biomes to research:
- What is the weather like?
- What animals would I see?
- What would I eat?
- Where is this biome?
- What kinds of plants live here?
Have the class agree on several questions that each group needs to research for their particular biome. Then have each group choose several other questions that they want to find about their biome. Each group should at the least find what region of the world their biome is in, the types of plants and animals that live there, and the types of weather they have
Have students spend time at the library or on the Internet researching their biome. Some useful websites are: http://mbgnet.net/, http://library.thinkquest.org/TQ0310225/ and http://library.thinkquest.org/05aug/00332/
Why should students collect evidence to answer questions?
How can I help my students collect evidence?
Once students have collected all of their information, have them create a presentation of their findings. Allow each group of students to choose their individual presentation formats. An important component of their biome presentation should be the creation of a food web that exists in their biome.
Why should students communicate and justify their findings?
How can I help my students communicate and justify their findings?
- Terrestrial biomes: tundra, taiga, deciduous, forest, grassland, desert, tropical rainforest
- Aquatic biomes: marine, freshwater
How Kirsten taught this lesson
Kirsten felt that her students had a pretty good understanding of food webs at this point in the ecosystems unit and wanted to make sure that they made connections between the living and non-living parts of ecosystems in their biomes project. She anticipated that her students would find a lot of good information about the different species that lived in the different biomes but wanted them to also understand that the differences they observe are due, in part, to the environmental characteristics of each biome.
As a result, she chose to scaffold the students' presentations by giving them some options, such as making a diorama or collage. She wanted to make sure that they included examples of producers, consumers, and decomposers in their biomes as well as representations of its non-living parts. Kirsten felt this more teacher-directed approach would help her students develop a deeper understanding of the differences between the Earth's biomes.