In 1542 the Spanish explorer Francisco de Orellana ventured into the
Amazon Basin and along the Rio Negro to hunt for the mythic city of El
Dorado and its rumored treasure of gold. Instead his expedition found a
network of farms, villages, and cities. “His chronicles describe large
villages, long-range trade networks, paramount chiefs almost like
nobility, and they talked about the Amazon being highly populated,”
says Neves.
As productive and lush as the rain forest appears, the soil it stands on is, literally, dirt poor
No one ever saw those populations again.
The first scientists who studied the Amazon found little evidence to support Orellana’s claims of large populations. As productive and lush as the rain forest appeared, the soil it stood on was, literally, dirt poor. Betty J. Meggers, a Smithsonian archaeologist who worked in the Amazon from the mid-1900s on, referred to the region as “a counterfeit paradise.” The apparent lushness existed only because the vegetation was so good at sucking up every speck of nutrient released from decaying leaves. Any nutrients remaining washed away in the frequent rains. In short, the local soil was ill-suited for agriculture, and without agriculture, societies would remain small.
The outcome of the slash-and-burn agriculture that is practiced today supports that view. In this method, settlers cut down forests and burn the cover in order to grow crops in the nitrogen- and mineral-rich ash that is left behind. But the soil in these denuded plots is productive for only a few years before it reverts to its original nutrient-scarce state. This lack of agricultural potential helped popularize a model of the pre-Columbian occupation that anthropologist Michael Heckenberger of the University of Florida at Gainesville describes as “the myth of Stone-Age savages frozen at the dawn of time.
Slash-and-burn agriculture involves burning forest cover which only briefly enriches the soil for crops.
If researchers can learn to replicate the rich black earth created by pre-Columbian inhabitants, small
farmers in the Amazon today could raise crops for years on the same fertile plot of land.
(Courtesy of Stephen A. Vosti, PhD.)
Heckenberger’s own experience had led him to question that perspective. In the early 1990s, while living with the Kuikuro, an indigenous tribe in the upper Xingu region about 600 miles southeast of Manaus, he discovered a ruling-class structure more complex than needed for a group of just 300 people. Could the region have had a grander past? When he dug beyond the village borders he found a giant plaza, roads, causeways, canals, and even bridges—the remains of an earlier, larger civilization.
In the mid-1990s Heckenberger invited Petersen, his former teacher, to spend time at his field site. After visiting the Kuikuro in the Xingu, the two men took a short excursion, traveling up the Rio Negro from its junction with the Amazon at Manaus. One day Heckenberger headed out by himself on a boat that ended up on a Rio Negro beach, where a farmer was tilling the soil and turning up mounds of broken ceramics embedded in coal-black terra preta. Heckenberger could see that this rich soil extended over an area two miles along the Rio Negro shore. He collected some pottery samples and took them back to show Petersen, a ceramics expert. The abundance of the pottery piqued Petersen’s growing interest in the mystery of lost Amazon settlements.
Enduring 100-degree heat, researchers excavate the Hatahara site
in the Amazon Project.
(Courtesy of Val Moraes)
In the months to follow, Heckenberger and Petersen worked to develop a project around the site with Neves, and the Central Amazon Project was born. The group wrote up institutional agreements, received permits, got seed money, and began fieldwork in 1995. When their early finds seemed to challenge Meggers’s vision of the pre-Columbian Amazon, they turned to a model proposed by Donald Lathrap, an archaeologist at the University of Illinois. During the 1960s, he had hypothesized—based on linguistic and ceramic evidence—that the confluence of the Amazon, Rio Negro, and Madera rivers may have been the heart of an agriculturally based civilization that once extended from the Caribbean to southern Brazil.
Heckenberger left the Central Amazon Project in 1999 to concentrate on the Kuikuro, but Petersen and Neves continued the effort. Over the years, excavation expanded beyond the original site, called Açutuba, to include other spots in a 20-square-mile area on the peninsula that juts between the Amazon and Rio Negro rivers. Gradually funding switched from U.S. institutions to predominantly Brazilian, and Neves took more of an oversight role. But Petersen continued to participate every summer. In a 2005 interview with the Vermont Quarterly, he called his central Amazon research “some of the richest, most exciting archaeology anywhere on the planet.”
