Rainforests are dense jungles found near the equator that receive high amounts of rainfall each year. They exist in Central and South America, Africa, Southern Asia, and Australasia. Though they cover only 6% of the earth's surface, rainforests are home to over half of all plant and animal species. The largest rainforest is the Amazon, which spans 5.5 million square kilometers across South America and contains one third of all species. Rainforests play an important role by stabilizing the climate, housing many unique species, and supporting tribal peoples, but they are being destroyed for timber, agriculture, grazing land, and development.