South America

South America

Central America

TERRITORY
In strictly geological, Central America is bordered to the north from the isthmus of Tehuantepec in southern Mexico, and to the south by the watershed of the rivers Atrato and Tuiria.
From the geological point of view, Central America is one of the most unstable of the earth’s crust and is located on the southern edge of the Caribbean Plate (see Plate Tectonics). From the Miocene, about 25 million years ago, the sinking of the oceanic crust beneath the margin determined the lifting and the emergence of the first plate forming a peninsula and an archipelago which, in later times, joined in an isthmus . During the same period occurred violent earthquakes and volcanic eruptions are still affecting the region and have created a landscape dotted with majestic cones produced by the eruptions of ash and lava, and beautiful lakes that were formed in the craters (calderas).
The territory of Central America is largely a bitter mountainous region characterized by the presence of numerous volcanoes, mostly inactive, some of which are more than 4000 m above sea level.
The only flat areas are represented by a narrow strip along the Pacific Ocean from which to sloping hills rise abruptly on the other side of the wider plain bathed by the Caribbean Sea. The two main steps that connect the mountain slopes through the highlands of Central America and can be found respectively in Nicaragua (from the mouth of the San Juan River to Lake Nicaragua) and Panama City (along the channel of the same name).

FLORA AND FAUNA
Central America is rich in vegetation. Dominant is the rainforest where, at lower altitudes to 1000 m, grow luxuriant palms, ferns, lianas and epiphytes, due to high rainfall and humidity of the region. At altitudes between 1000 and 1600 m grow forests of pine and oak trees similar to those of the Mexican highlands. The higher regions of Guatemala and Costa Rica have a grassy vegetation and in areas not exposed to the trade winds predominate traits of bush and savannah.The fauna has affinities with that of South America and includes peccaries and possums as well as jaguars, ocelots, Jaguarundi (Felis yagouaroundi) and margay (Felis wiedii), belonging to the family Felidae, armadillos, anteaters and sloths. The puma, gray foxes and coyotes are originating in North America, like the deer. The large manatee, which eats aquatic plants, survives in isolated lagoons of the eastern regions, it is hunted for food like a kind of large sea turtle (Chelonia mydas) and the iguana. There are numerous species of reptiles, including the boa constrictor and a particularly poisonous species, Lachesis. Parrots, quetzals (Pharomachrus mocinno) and toucans are very common species in the region. Varies is also the fish, among which signals the shark of Lake Nicaragua.

South America

TERRITORY
The territory of the continent can be divided into three physical regions: the Andes, the central plains and the Eastern Highlands. The Andes rise abruptly from the northwestern and western coasts of the continent and form a single chain in northern Venezuela and along much of southern Chile and Argentina, while the center is divided into two or three parallel chains called cordilleras (Spanish cordilleras ). Among the numerous peaks over 5000 m above sea level, there are many active volcanoes located in south-central Chile, Peru, in southern Bolivia and Ecuador.

The vast highlands of Guyana to the north-east and Brazil to the east are hilly, wide boards and high mesas. The boards are higher and less extensive in the highlands of Guyana, while the plateau of Brazil reaches the highest altitudes in the mountains along the east coast. The soils of these plateaus are generally poor, but in many valleys the soil is made fertile by the presence of basaltic rocks. The plateau of Patagonia is lower and relatively flat; here the exploitation of fertile soil is hampered by difficult weather conditions.

To the north of the continent lies the flat area of ​​the Orinoco basin, which includes the llanos – a region of low alluvial plains and mesas – and an extensive system of valleys converging on the Amazon between the rivers Caquetá and Madeira. The Amazon basin has a gently hilly territory. Further south lie the shallow valleys and plains of the Gran Chaco and the Pampas that blend in flood plains and swampy rivers Paraguay and Parana.

FLORA
The vegetation of South America varies according to different climatic regions. Areas from the tropics have a dense cover of rainforest or jungle. This region, the largest in the world, covers most of the equatorial belt, including the coastal areas of Brazil and the lower slopes of the Andes, and is full of tropical plants from hardwood trees, palms, tree ferns, bamboo and vines. In areas with winter drought, especially along the Venezuelan coast, in the northeast of Brazil and the Gran Chaco, are sparse forests and scrub. Among these drier areas and rainforest areas appear high herbaceous vegetation (savannas, or campos) and mixed woodland to grassland (campos cerrados). In southern Brazil and along the slopes of the Andes grow and deciduous forests semidecidui. The Gran Chaco is characterized by grassy plains and scrub shrub, while the flat Pampas of Argentina have vast central prairies. To the south an area of ​​steppe and scrub (upstream) marks the transition to the low scrub and herbaceous vegetation that characterizes the region driest and coldest part of Patagonia. Along the Pacific coast, going north, the forest gives way to scattered forests, shrubs and meadows of central Chile, and finally to the bush and desert vegetation prevailing in northern Peru and in the highest areas of mountain slopes .

FAUNA
South America, Central America, the plains of Mexico and the West Indies belong to a single zoogeographic region, usually called the Neotropical region. The fauna is characterized by a great variety of species found only in this continent and including monkeys, vampires and many rodents. In the region of a single species of bear and lives a type of camelid, llama. Characteristic of the continent are also the vicuña, alpaca, jaguars, peccaries, giant anteater and the coati. As for birds, many are the families of Neotropical birds and marine, as well as those of hummingbirds or humming-birds (500 species), the thraupidi and ara. Among the larger birds include rheas, condors and flamingos. Among the reptiles there are boas and anacondas, iguanas, caimans and crocodiles. Of various species and a large number are freshwater fish, insects and invertebrates. The Galapagos Islands are famous as a habitat of large turtles and other reptiles, and birds found only in this archipelago.

Guido Bissanti