Biomes are the major, easily recognizable associations between plants and animals.
Each biome has a unique climatic condition heavily influenced by rainfall (or availability of water) and to a lesser extent light, temperature and other abiotic factors. Each biome can be characterized by a particular plant species which predominates.
Biomes are subdivided into ecological communities, each with a unique association of plant and animal populations.
Biomes follow a characteristic distribution pattern north or south of the equator, or by elevation based on climatic factors. Generally traveling north or south of the equator one might encounter the following biomes:
Most Tropical rain forests are typified by the following:
- 250-450 cm of rainfall per year (100-175 inches)
- Most occur on or near the equator
- Rain fall is generally evenly distributed throughout the year
- Trees which form strata or layers, the tallest being 30 to 45 meters high (100-170 feet tall)
Visit the National Geographic's page describing the tropical rain forest.
Deserts exhibit the following conditions:
Receive less than 25 cm (10 inches) of highly seasonal rainfall per year.
Other adaptations include recessed stomata guarded by fine hairs, small leathery leaves, long dormant periods, and specialized photosynthetic cycles (CAM plants).
Annual plants can flower rapidly and produce seeds which last many years waiting for adequate rainfall.
Additional Information about deserts includes the following sites:
Animals are adapted to desert conditions both physically and behaviorally. Many are nocturnal and live underground in humid burrows. Other animals hibernate in their burrows during the day while temperatures are high. This behavior is called estivation.
Modified Nov. 6, 2002