单选题 The Mystery of the Nazca Lines
    A. If you visit the Peruvian coastal desert from north to south, you will note that sporadically you come upon a green and fertile valley surrounded by sand. The valleys of the Peruvian Pacific coast are like elongated oasis, through which run narrow and torrential rivers that originate in the snow-capped mountains of the Andes and which flow to the Pacific Ocean. As you travel more towards the south, these valleys become smaller and the rivers are narrower. Many of these rivers nm dry for most part of the year with the exception of the rainy season in the mountains (from December to March).
    B. Nazca is one of these valleys. Here an important civilization developed during the first six centuries after Christ. It was a culture made up of noteworthy textile weavers and potters (the best paintings of ancient Peru can be found on the ceramics from Nazca. Great desert plains and plateaus extend to the north and south of this region, a land of complete aridness where there is no vegetation, where the air is very dry and where it seldom rains. Compared to the other nearby valleys, this valley is inhabited by no one.
    The Nazca Lines
    C. Across the plain between the Inca and Nazca Valleys, there lies an area measuring 37 miles long and mile wide, on which there is an assortment of perfectly straight lines, many running parallel, others intersecting, forming a grand geometric form. In and around the lines there are also trapezoidal zones, strange symbols, and pictures of birds and beasts all etched on a giant scale that can only be appreciated from the sky.
    D. The figures come in two types: biomorphs and geoglyphs. The biomorphs are some 70 animal and plant figures that include a spider, hummingbird, monkey and a 1,000-foot-long pelican. The biomorphs are grouped together in one area on the plain. Some archaeologists believe they were constructed around 200 B.C., about 500 years before the geoglyphs.
    E. There are about 900 geoglyphs on the plain. Geoglyphs are geometric forms that include straight lines, triangles, spirals, circles and trapezoids. They are enormous in size. The longest straight line goes nine miles across the plain.
    F. The forms are so difficult to see from the ground that they were not discovered until the 1930's when aircraft, when surveying for water, spotted them. The plain, crisscrossed, by these giant lines with many forming rectangles, has a striking resemblance to a modem airport. The Swiss writer, Erich von Daniken, even suggested they had been built for the convenience of ancient visitors from space to land their ships. As tempting as it might be to subscribe to this theory, the desert floor at Nazca is soft earth and loose stone, not tarmac, and would not support the landing wheels of either an aircraft or a flying saucer.
    How Were They Built?
    G. Straight lines can be made easily for distances with simple tools. Two wooden stakes placed as a straight line would be used to guide the placement of a third stake along the line. One person would sight along the first two stakes and instructs a second person in the placement of the new stake. This can be repeated as many times as needed to make an almost perfectly-straight line miles in length. The symbols were probably made by drawing the desired figure at some reasonable size, then using a grid system to divide it up. The symbol could then be redrawn at full scale by recreating the grid on the ground and working on each individual square one at a time.
    So Why Are the Lines There?
    H. The American explorer Paul Kosok, who made his first visit to Nazca in the 1940s, suggested that the lines were astronomically significant and that the plain acted as a giant observatory. He called them 'the largest astronomy book in the world.' Gerald Hawkins, an American astronomer, tested this theory in 1968 by feeding the position of a sample of lines into a computer and having a program calculate how many lines coincided with an important astronomical event. Hawkins showed the number of lines that were astronomically significant were only about the same number that would be the result of pure chance. This makes it seem unlikely Nazca is an observatory.
    I. Perhaps the best theory for the lines and symbols belongs to Tony Morrison, the English explorer. By researching the old folk ways of the people of the Andes mountains, Morrison discovered a tradition of wayside shrines (神殿) linked by straight pathways. The faithful would move from shrine to shrine praying and meditating. Often the shrine was as simple as a small pile of stones. Morrison suggests that the lines at Nazca were similar in purpose and on a vast scale. The symbols may have served as special enclosures for religious ceremonies.
    J. Recently two researchers, David Johnson and Steve Mabee, have advanced a theory that the geoglyphs may be related to water. The Nazca plain is one of the driest places on Earth, getting less than one inch of rain a year. Johnson, while looking for sources of water in the region, noticed that ancient aqueducts, called puqulos, seemed to be connected with some of the lines. Johnson thinks that the shapes may be a giant map of the underground water sources traced on the land. Mabee is working to gather evidence that might confirm this theory.
    K. Other scientists are more skeptical, but admit that in a region where finding water was vital to survival, there might well be some connection between the ceremonial purpose of the lines and water. Johan Reinhard, a cultural anthropologist with the National Geographic Society, found that villagers in Bolivia walk along a straight pathway to shrines while praying and dancing for rain. Something similar may have been done at the ancient Nasca lines.
    L. The lines at Nazca aren't the only landscape figures Peru boasts. About 850 miles south of the plain is the largest human figure in the world laid out upon the side of Solitary Mountain. The Giant of Atacama stands 393 feet high and is surrounded by lines similar to those at Nazca.
    M. Along the Pacific Coast in the foothills of the Andes Mountains is etched a figure resembling a giant candelabrum. Further south, Sierra Pintada, which means 'the painted mountain' in Spanish, is covered with vast pictures including spirals, circles, warriors and a condor. Archaeologists speculate that these figures, clearly visible from the ground, served as guideposts for Inca traders.
    Preserving the Nazca Lines
    N. It is difficult to keep the Nazca Lines free from outside intervention. As with all ancient ruins, such as Machu Piccu, weather by wind and rain, and human tampering will take their toll on these ancient Lines. In recent years the Nazca Lines have suffered gradual destruction, as tomb raiders seeking pre-Inca artifacts scar the terrain with hundreds of burrows, garbage, among other waste material. A boom in copper and gold mining-including a mine built in 1997 a few feet from a 2,000-year-old, two-mile-long trapezoid—is defacing parts of the Nazca Lines with tracks from truck traffic.
    O. The damage to the Lines underscores Peru's desperate struggle to preserve its national patrimony. Archaeologists say they are watching helplessly as the quest for scholarship and conservation in a country viewed as the cradle of New World civilization is losing out to commercial interests, bleak poverty and the growing popularity of heritage sites as tourist attractions.

问答题     In comparison with other nearby valleys, Nazca has no residents.

问答题     According to Erich von Daniken, the function of those forms across the plain was to help space visitors land their ships.

问答题     Gerald Hawkins didn't agree with Paul Kosok's theory that Nazca was an observatory.

问答题     According to some archaeologists, the biomorphs were constructed earlier than the geoglyphs.

问答题     The river water in the valleys of the Peruvian Pacific coast comes from mountains of the Andes.

问答题     A researcher named Mabee is working to collect evidence to confirm the theory that the geoglyphs are related to water.

问答题     Recently, the Nazca Lines are being damaged by the waste materials left by tomb raiders who go there to seek pre-Inca artifacts.

问答题     To build a straight line miles in length, the first thing to be done is to place two wooden stakes as a straight line.

问答题     According to Morrison, the symbols at Nazca were made to serve as enclosures for religious ceremonies.

问答题     The figures at Sierra Pintada are believed to have been made in purpose of directing the Inca traders.