Land carvings attest to Amazon’s lost world
Edmar Araujo still remembers the awe. As he cleared trees on his family’s land decades ago near Rio Branco, an outpost in the far western reaches of the Brazilian Amazon, a series of deep earthen avenues carved into the soil came into focus.
“These lines were too perfect not to have been made by man,” said Araujo, a 62-year-old cattleman. “The only explanation I had was that they must have been trenches for the war against the Bolivians.”
But these were no foxholes, at least not for any conflict waged here at the dawn of the 20th century.
According to stunning archaeological discoveries here in recent years, the earthworks on Araujo’s land and hundreds like them nearby are much, much older – potentially upending the conventional understanding of the world’s largest tropical rain forest.
The deforestation that has stripped the Amazon since the 1970s has also exposed a long-hidden secret lurking underneath thick rain forest: flawlessly designed geometric shapes spanning hundreds of yards in diameter.
Alceu Ranzi, a Brazilian scholar who helped discover the squares, octagons, circles, rectangles and ovals that make up the land carvings, said these geoglyphs found on deforested land were as significant as the famous Nazca lines, the enigmatic animal symbols visible from the air in southern Peru.
“What impressed me the most about these geoglyphs was their geometric precision, and how they emerged from forest we had all been taught was untouched except by a few nomadic tribes,” said Ranzi, a paleontologist who first saw the geoglyphs in the 1970s and, years later, surveyed them by plane.
For some scholars of human history in Amazonia, the geoglyphs in the Brazilian state of Acre and other archaeological sites suggest that the forests of the western Amazon, previously considered uninhabitable for sophisticated societies partly because of the quality of their soils, may not have been as “Edenic” as some environmentalists contend.
Instead of being pristine forests, barely inhabited by people, parts of the Amazon may have been home for centuries to large populations numbering well into the thousands and living in dozens of towns connected by road networks, explains the American writer Charles C. Mann. In fact, according to Mann, the British explorer Percy Fawcett vanished on his 1925 quest to find the lost “City of Z” in the Xingu, one area with such urban settlements.
As a result of long stretches of human habitation, South America’s colossal forests may have been a lot smaller at times, with big areas resembling relatively empty savannas. Such revelations do not fit comfortably into today’s politically charged debate over razing parts of the forests, with some environmentalists opposed to allowing any large-scale agriculture, like cattle ranching and soybean cultivation, to advance further into Amazonia.
Scientists here say they, too, oppose wholesale burning of the forests, even if research suggests that the Amazon supported intensive agriculture in the past. Indeed, they say other swaths of the tropics, notably in Africa, could potentially benefit from strategies once used in the Amazon to overcome soil constraints.
