Background information; by edgardowelelo@yahoo.com.
South America is 7,240 km long, stretching from the Caribbean (West Indies) almost to the Antarctic, no other continent reaching so close to the polar landmass of Antarctica. The continent of South America is mostly tropical, with the southern part extending into a temperate zone. In the western part, the Andes rise like an enormous wall along almost the whole Pacific coast from north to south, adding a rich spectrum of climates and habitats. On the eastern side, bordering the Atlantic, mighty Brazilian sierras distinguish the coastline: high plateaus and lowland river basins occupy the interior. South America has more rainforests, mainly in the Amazon Basin, than any other tropical continent. These rainforests support thousands of plant and animal species, including at least 2,500 species of trees. In addition to the rainforests, the variety of vegetation zones is very great, ranging from deciduous temperate forests and steppes to arid brush lands, deserts, and sub Antarctic moorlands. There are savannas and grasslands of various types: Ilanas, campos, and pampas, and paramos (highland moors). The fauna of South America is rich and diverse with many unique and highly specialized mammalian species and among birds, the greatest number of species known to inhabit any continent. Because their habitats have been destroyed, a great number of animal species have been exterminated in South America, particularly in the Caribbean, where endemic species are extremely vulnerable to abrupt changes in the environment.
