Geography of South America Great American Interchange. The Andes, likewise a comparatively young and seismically restless mountain range, runs down the western edge of the continent; the land to the east of the northern Andes is largely tropical rain forest, the vast Amazon River basin. The continent also contains drier regions such as eastern Patagonia and the extremely arid Atacama desert. The South American continent also includes various islands, most of which belong to countries on the continent. The Caribbean territories are grouped with North America. The South American nations that border the Caribbean Sea—including Colombia, Venezuela, Guyana, Suriname, and French Guiana—are also known
Smallest organisms were first described in 1996 by Philippa Uwins of the University of Queensland. Smallest organisms The smallest organisms found on Earth can be determined according to various aspects of organism size; including volume, mass, height, length, or genome size. Given the incomplete nature of scientific knowledge, it is possible that the smallest organism is undiscovered. Furthermore, there is some debate over the definition of life, and what entities qualify as organisms; consequently the smallest known organism (microorganism) is debatable. Many biologists consider viruses to be non-living because they lack a cellular structure and cannot metabolize by themselves, requiring a host