Andes Mountains

The Andes Mountains are a series of extremely high plateaus surmounted by even higher peaks that form an unbroken rampart over a distance of some 5,500 miles (8,900 kilometres)—from the southern tip of South America to the continent’s northernmost coast on the Caribbean.

Some historians believe that the "Andes" in Andes Mountains comes from the Quechuan word anti (“east”). Others suggest it is derived from the Quechuan anta (“copper”). It perhaps is more reasonable to ascribe it to the anta of the older Aymara language, which connotes copper color generally.

About 250 million years ago, the crustal plates constituting Earth’s landmass were joined together into the supercontinent Pangaea. The breakup of Pangaea dispersed these plates outward, and the collision of two of these plates—the continental South American Plate and the oceanic Nazca Plate—gave rise to the mountain-building activity that produced the Andes Mountains.

The highest point in the Andes Mountains is Mount Aconcagua, located in the Southern Andes Mountains. Although its peak is in Argentina, its western flanks build up from the coastal lowlands of Chile, just north of Santiago. Mount Aconcagua is the highest point in the Western Hemisphere at 22,831 feet (6,959 metres).

The highest altitude in the Andes Mountains at which people have resided permanently is 17,100 feet (5,212 metres; they were shepherds in southern Peru) and as temporary workers 18,500 to 19,000 feet (5,639 to 5,791 metres; at the Carrasco Mine in the Atacama Desert in Chile). The shortage of oxygen at high altitude, especially above 12,000 feet (3,658 metres), imposes deep adaptative changes even within the cells of the body.