Scientists believe that savanna plant species may have developed this strategy to take advantage of the season variance of the start of the rains. Climatically, these biomes are characterized by distinct wet and dry seasons. Temperatures are hot all year long. Savanna vegetation is typical composed of a mixture of grass and trees. The savanna biome constitutes extensive areas in eastern Africa, South America, and Australia.
Zebras are a common grazer of the African savanna.
Savannas are also home to a number of predator species who prey on grazing animals. The soils are more nutrient rich than tropical forest soils. Some soils become extremely dry because of evaporation and form laterite layers. Tropical Rainforest Tropical rainforests occur in a broad zone outside the equator . Annual rainfall, which exceeds 2000 to 2250 millimeters, is generally evenly distributed throughout the year.