Climate decides what can grow. Where the climate is alike, similar plants grow, and similar animals live among them, even on different continents.
Key idea
A biome is a large region with a similar climate, plants and animals. The main land biomes: tropical rainforest, savanna, desert, temperate grassland, temperate forest, Mediterranean shrubland, taiga (boreal forest) and tundra.
| Biome | Where | Plants |
|---|---|---|
| Tropical rainforest | Amazon, Congo Basin, Southeast Asia | Tall evergreen trees in layers |
| Savanna | East Africa, northern Australia, Brazil | Grasses with scattered trees |
| Desert | Sahara, Arabia, Australia, the U.S. Southwest | Cactuses and shrubs, far apart |
| Temperate grassland | Great Plains, the Pampas, the steppes of Eurasia | Grasses, few trees |
| Temperate deciduous forest | Eastern U.S., western Europe, eastern China | Trees that drop leaves in fall |
| Mediterranean shrubland | Around the Mediterranean, California, central Chile | Tough shrubs and small oaks |
| Taiga | Across Canada, Scandinavia and Russia | Spruce, fir and pine |
| Tundra | Arctic coasts, high mountains | Mosses, lichens, low shrubs; no trees |
Why it works
Plants are fixed in place, so they must survive the local climate all year. Broad thin leaves lose water fast, so they work where it is wet; needles survive cold and dry winters; cactuses store water; grasses regrow quickly after drought or fire. The same problems get similar solutions: deserts in Africa and the Americas both have spiny, water-storing plants, even though the plants are not related.
Worked example: Name the biome
A region has long, very cold winters, short summers, and forests of spruce and fir with moose and wolves. Which biome?
- Conifer forests in a cold climate are taiga.
Answer: Taiga (boreal forest).
Common mistake
Thinking a biome is a country, or the home of one animal. A biome is defined by climate and plants, and one biome can stretch across many countries and continents: the taiga runs from Alaska across Canada and from Norway across Russia. One country, such as Brazil or the United States, can hold several biomes.