Shady knew that the reeds were ideal subjects for radiocarbon dating and could make her case. In 1999, she sent samples of them to Jonathan Haas at Chicago’s FieldMuseum and to Winifred Creamer at NorthernIllinoisUniversity. In December 2000, Shady’s suspicions were confirmed: the reeds were 4,600 years old. She took the news calmly, but Haas says he “was virtually in hysterics for three days afterward.” In the April 27, 2001, issue of the journal Science, the three archaeologists reported that Caral and the other ruins of the SupeValley are “the locus of some of the earliest population concentrations and corporate architecture in South America.” The news stunned other scientists. “It was almost unbelievable,” says Betty Meggers, an archaeologist at the Smithsonian Institution. “This data pushed back the oldest known dates for an urban center in the Americas by more than 1,000 years.”
What amazed archaeologists was not just the age but the complexity and scope of Caral. Pirámide Mayor alone covers an area nearly the size of four football fields and is 60 feet tall. A 30-foot-wide staircase rises from a sunken circular plaza at the foot of the pyramid, passing over three terraced levels until it reaches the top of the platform, which contains the remains of an atrium and a large fireplace. Thousands of manual laborers would have been needed to build such a mammoth project, not even counting the many architects, craftsmen, supervisors and other managers. Inside a ring of platform pyramids lies a large sunken amphitheater, which could have held many hundreds of people during civic or religious events. Inside the amphitheater, Shady’s team found 32 flutes made of pelican and condor bones. And, in April 2002, they uncovered 37 cornets of deer and llama bones. “Clearly, music played an important role in their society,” says Shady.
The perimeter of Caral holds a series of smaller mounds, various buildings and residential complexes. Shady discovered a hierarchy in living arrangements: large, well-kept rooms atop the pyramids for the elite, ground-level complexes for craftsmen, and shabbier outlying shantytowns for workers.
But why had Caral been built in the first place? More important, why would people living comfortably in small communities perched on the Pacific Ocean with easy access to abundant marine food choose to move inland to an inhospitable desert? If she could answer this question, Shady believed she might begin to unravel one of the knottiest questions in the field of anthropology today: What causes civilizations to arise? And what was it about the desert landscape of Peru’s SupeValley that caused a complex, hierarchical society to flourish there?
Her excavations convinced Shady that Caral had served as a major trade center for the region, ranging from the rain forests of the Amazon to the high forests of the Andes. She found fragments of the fruit of the achiote, a plant still used today in the rain forest as an aphrodisiac. And she found necklaces of snails and the seeds of the coca plant, neither of which was native to Caral. This rich trading environment, Shady believes, gave rise to an elite group that did not take part in the production of food, allowing them to become priests and planners, builders and designers. Thus, the class distinctions elemental to an urban society emerged.