Researchers investigating a long-ignored Peruvian archaeological site say they have determined that it is the oldest city in the Americas, with a complex, highly structured society that flourished at the same time that the pyramids were being built in Egypt.
The finding is forcing a re-evaluation of ideas about the rise of the earliest civilizations in the New World, particularly how and when ancient peoples moved from the coasts, with reliable ocean food sources, to inland settlements with less stable supplies of food.
The vast site, called Caral, is one of about a dozen large sites in the Supe Valley, just inland from the Pacific coast in central Peru, 120 miles north of Lima. New radiocarbon dating shows that Caral flourished for five centuries, starting about 2600 B.C., with public architecture (including six stone platform mounds up to 60 feet high), ceremonial plazas and irrigation — all signs of a society with strong, centralized leadership.
"Now we've got to deal with these sites as being the earliest things going on in South America — by hundreds of years," said one of the researchers, Dr. Jonathan Haas, MacArthur curator of anthropology at the Field Museum in Chicago.
Dr. Shelia Pozorski, a professor at the University of Texas-Pan American who with her husband, Tom, has studied other Andean sites for 30 years, said the finding helped overturn what has been known as the maritime hypothesis. This is the idea that complex Andean societies, precursors of the Incas, evolved from the coast, where reliance on fishing required some level of social organization, to inland sites, developing fully only when ceramics appeared around 1800 to 1500 B.C.
"It makes it more of a quantum leap, rather than a moderately rapid crawl," Dr. Pozorski said. "Rather than having coastal precursors to inland complexity, the two areas are developing at the same time."
Another expert in Andean anthropology, Dr. Richard L. Burger, director of the Peabody Museum of Natural History at Yale, described the new work as "the nail in the coffin of the maritime hypothesis."
Dr. Haas said that before the rise of Caral civilization in the region amounted to a few small coastal villages, with perhaps a hundred people or so in each, and other smaller bands of hunter-gatherers. By 2700 B.C., he said, several larger villages began to appear.
"But then all of a sudden you've got Caral, and probably at least one of its neighbors," Dr. Haas said. "It's bigger by an order of magnitude than anything before." While it is not yet possible to estimate the population of Caral — much more archaeological work remains to be done — Dr. Haas said that the number was in the thousands, not hundreds.
Dr. Haas studied Caral with his wife, Dr. Winifred Creamer, a professor of anthropology at Northern Illinois University, and Dr. Ruth Shady of the Universidad Nacional Mayor de San Marcos in Peru. Their paper dating and describing the site is being published today in the journal Science.
Caral was first discovered by archaeologists about 1905, and has been explored only intermittently. The site's central area covers more than 150 acres and is dominated by the platform mounds, the largest of which is 450 by 500 feet at the base, and two sunken circular plazas, one of them 150 feet in diameter. There are also remains of several types of residential structures.
Anthropologists have largely ignored Caral, considering it puzzling, Dr. Haas said.
Pottery has never been found at the site, and its absence would ordinarily suggest that the civilization existed before 1800 B.C. But Dr. Haas said that for many experts the sheer size of the place — and the level of societal complexity that it implies — meant that it had to be newer. The consensus, he said, was that "something that big cannot be that early." So the lack of ceramics, by this way of thinking, was only an anomaly.
But Dr. Haas and his colleagues felt that the lack of ceramics meant, in fact, that Caral was a pre-ceramic site. "All three of us had a fundamental belief that these sites were really early," he said.
The belief was confirmed through the radiocarbon dating of plant fibers found at the site, including reeds that had been woven into loose sacks, known as shicra bags.
Those bags played an essential role in the mound-building process. Caral's workers filled them with rocks at a hillside quarry, carried them on their shoulders more than a mile to the construction site and left them, bag and all, inside the mounds' retaining walls.
Since the largest mound has a volume of more than 250,000 square yards, construction required many bags, and many highly organized workers.
"This site just consumed labor," Dr. Haas said, and obviously had a lot to consume. Caral and nearby sites represented a flourishing, well- developed society, with enough food, other resources and organization to build these great mounds. "There's a surplus at these sites," Dr. Haas said, "and it's not going into storage of foodstuffs. It's going into construction."
The people of Caral practiced agriculture, and given the arid conditions, the site's size and its location some 30 feet above the flood plain of the Supe River, they had to have used irrigation. A present-day irrigation canal nearby was almost certainly the site of an ancient one, Dr. Haas said.
The inhabitants grew cotton and vegetables, including squash and beans. But archaeological work shows that they relied largely on fish and shellfish as their main source of protein, brought from the coast about 15 miles away. The remains of clams, sardines and anchovies were found at the site.
Dr. Burger said the fact that much of the food came from the coast only reinforced the limitations of the maritime hypothesis.
"There was an interdependence between shoreline sites rich in protein and agricultural sites rich in carbohydrates," Dr. Burger said. The Caral work, he added, shows that rather than a theory that has society developing in one area, development "has to be thought of in terms of a much larger, more diverse set of adaptations."
File Date: 5.02.01