There are many different kinds of plants and animals on the Earth, but only certain kinds are naturally found at any particular place. (We are not counting zoos here!) For example, cacti are found in the desert, polar bears are found in the Arctic, and elephants are found in central Africa and India. So, why don't people living in south Texas have to be on the lookout for snow leopards, or why don't kids in Minnesota have to worry about finding giant boa constrictors in their back yards? It is because these animals are not adapted to live in the average weather conditions found in Texas or Minnesota.
These average weather conditions, such as the range of temperature and rainfall that typically occur in a particular location like Minnesota, are called the climate of that location. Some climates are hot, some are cold, some are wet and some are dry. "Adapted" means that a plant or animal has inherited certain characteristics that enable it to live in one type of climate or another. For example, polar bears have a layer of fat under their skin and a heavy fur coat to help them withstand arctic cold. They would have a difficult time trying to survive in a hot climate.
Plants and animals don't live in isolation, but they live together with other plants and animals in an interdependent group called an ecological community. If you think about it for a moment, you will realize that all of the plants and animals in a particular ecological community must be adapted to the same climate so that they can all live in the same location.
A distinct ecological community of plants and animals living together in a particular climate is called a "biome." Scientists have divided the broad spectrum of climates and ecological communities found on Earth into biomes in different ways - some with many divisions, some with only a few. Here is a commonly found grouping:
The locations of these different biomes across the face of Earth are shown in different colors in the map* above. The Arctic tundra is light tan (ice is white). Mid-Latitude deciduous forests are greenish-yellow and yellowish-green. Deserts are mostly gray. Tropical rainforests are green. Tropical savannahs are light green and dark yellow. Areas of taiga are dark green and gray-green. To find out more about each of the biomes, just click on one of the spots on the map or use the navigational bar at the right of the page.
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