Vegetation and Wild Animals
South America's natural vegetation follows closely the continent's climatic zones. In the Amazon Basin and other tropical-rainy regions are vast rain forests. Here, dense stands of tall hardwood and softwood trees cover vast areas. In the Amazon Basin much of the forest is being cleared and burned to provide land for settlement and farming. Farther from the Equator, as rainfall decreases and a dry season begins, the rain forest gradually gives way to less dense tropical forest and then to grasses.
Where the dry season lasts six months or more, savannas are dominant. These regions of tall grasses with scattered patches of trees occupy the Llanos of Colombia and Venezuela and large parts of southern Brazil. Along permanent streams in savannas, where moisture is abundant, thick forests flourish. Drought-prone northeastern Brazil is mostly a scrubby woodland of thorny bushes and other plants that require little water.
Woodland and grassland in southern Brazil merge southward with the scrub of the Gran Chaco and the grassy plains of the Pampas. Much of Patagonia is covered with semidesert plants, including shrubs and grasses.
On the humid eastern slopes of the Andes from Venezuela south through Bolivia, vegetation changes with increasing altitude. Tropical forests at the lower levels give way to subtropical trees, which fade out at higher elevations and are replaced by grasses. The high Andean plateaus and basins are nearly all sparsely covered grasslands. Barren conditions prevail on the arid Pacific coast from Peru southward through the Atacama Desert of northern Chile. On southern Chile's rainy slopes are dense mixed forests of beech, cedar, fir, and other middle-latitude species.
A rich variety of birds, reptiles, insects, fish, and small mammals abounds in South America, especially in tropical regions. There are, however, no mammals comparable in size to the lion, rhinoceros, or elephant. Nor are there wild horses, antelopes, or their near relatives. The larger animals are mostly carnivores of the cat family, including the jaguar, cougar, and ocelot.
Other mammals include such tropical vegetarians as the tapir, sloth, marsh deer, and capybara. The latter, which reaches a length of four feet (1.2 m), is the world's largest rodent. Howler monkeys, spider monkeys, and marmosets are among the many primates of the tropical forest. Guinea pigs and agouti, both common rodents, are widely hunted for food.
In Andean forests lives the spectacled bear, the only South American bear. Higher in the Andes are found the guanaco and vicuña, members of the camel family and close relatives of the domesticated llama and alpaca.
Nowhere in the world is there as great a variety of birds as in South America. More than 1,500 species have been identified, many of them living in the Amazon Basin and the rainy forests of western Colombia. The cock of the rock, the hoatzin, and many colorful toucans, parrots, and macaws are all forest dwellers. Largest of the continent's birds is the flightless, ostrich-like rhea. The majestic Andean condor has the largest wingspread of any South American bird. Penguins live on the Pacific coast from Peru southward. Many birds that breed in North America migrate here to escape the cold winters—among them hawks, shorebirds, warblers, and swallows.
Snakes, alligators, lizards, and amphibians are plentiful. Notable poisonous snakes are the bushmaster and fer-de-lance; nonpoisonous types include some of the world's largest snakes, such as the anaconda and boa constrictor. Swamps and marshes are home to alligators and their close relatives, caimans, as well as turtles, frogs, and more unusual species such as the Surinam toad. Such fish as piranha, catfish, and electric eels live in many of South America's rivers, which are also the native habitat of such aquarium species as the angelfish, tetra, and hatchetfish.
