Passage 5

Questions 21 to 25 are based on the following passage.

Potatoes are a tuber-producing crop originally grown in the Americas. Over 200 varieties of wild potatoes grow from what is now Colorado to what are now Chile and Argentina. The native peoples of the Andean region of South America were the first to domesticate potatoes and to cultivate them as a food crop. The earliest potato, found in an archaeological site in central Peru, has been dated back to about 8000 B.C.. Scientists believe that American Indians began domesticating potatoes at the end of the Ice Age. Four thousand years later, native peoples living in the Andean highlands had begun to rely on potatoes as a major part of their diet. By about 2000 B.C.. Indians in the coastal region of what is now Peru were also cultivating this crop extensively.

During the reign of the Inca, who established their empire in what is now Peru in about A.D.1000, American Indian farmers were growing not only white potatoes but red, yellow, black, blue, green, and brown ones as well. They were deliberately developing potatoes of varying sizes and shapes that would do well under a number of growing conditions. Because potatoes were easily grown, flourish in a number of climates, and high in vitamin C, they were an efficient way of meeting dietary needs.

In 1531, when Spanish conqueror Francisco Pizarro landed in what is now Peru, the native Andean peoples had developed about 3,000 types of potatoes and had also invented a method to freeze-dry them for storage. The Inca, who called potatoes papas, ate boiled potatoes as a vegetable and also made a kind of unleavened potato bread made from flour that had been ground from freeze-dried potatoes. They also added this potato flour to soups and stews and made porridge from it.

Pedro de Cieza, who traveled with Francisco Pizarro's expedition, compared potatoes to chestnuts. Because the tubers grew underground and were small, the Spaniards believed potatoes were truffles (块菌) and began calling them tartuffo. When English explorer Sir Francis Drake crossed the Strait of Magellan, he ate potatoes on the coast of what is now Chile that same year. Yet, historians are uncertain exactly whether the Spaniards or the English brought potatoes to Europe.

 The earliest potato was found in ______.