Researchers discovered more than 450 mysterious earthworks in the Amazon rainforest. The earthworks were discovered using drones, which fly over the western Brazilian Amazon. It is believed that the monuments are more than 2,000 years old.
The age of the discovered earthworks places them well before any European visited Southern America, with ancient indigenous tribes building them thousands of years before the first expeditions discovered America.
Earthworks are found in Acre, a state in Brazil that is in the middle of the Amazon rainforest. The monuments are geometrical geoglyphs, large motifs created on the ground. They are often formed by natural causes such as trees, stones or earth.
The main reason for the discovery is a massive deforestation currently happening in Brazil. Each year massive areas of rainforest are cut down in order to make a place for crop fields and for use in industry. Without deforestation, the monuments wouldn’t be found, since they were hidden by trees.
Jennifer Watling, from the University of Sao Paolo’s Museum of Archaeology and Ethnography and one of the researchers who found earthworks believes that the discovery could challenge the accepted belief that the Amazonian forests are ecosystems that weren’t affected by humans until recently.
By reconstructing two sites, the researchers found that the ancient tribes made clearings in te forest in order to build the geoglyphs. While the tribes did clear parts of the wood, it has been found that they weren’t burning it or cut the trees.
Another interesting discovery regarding the earthworks is that the indigenous tribes, aside from making clearings, were shaped the forest by encouraging the growth of some plant species.
The study reads: “We show that bamboo forest dominated the region for ≥6,000 y and that only small, temporary clearings were made to build the geoglyphs; however, construction occurred within the anthropogenic forest that had been actively managed for millennia. In the absence of widespread deforestation, exploitation of forest products shaped a largely forested landscape that survived intact until the late 20th century.”
The researchers believe the earthworks could have been used as ritual sites since they found artifacts near the earthworks. Watling stated that the monuments are similar to Stonehenge. She said that “It is interesting to note that the format of the geoglyphs, with an outer ditch and inner wall enclosure, are what classicly describe henge sites. The earliest phases at Stonehenge consisted of a similarly layed-out enclosure.”
The researchers noted that, although their study found that the Amazonian rainforest was altered by humans thousands of years before modern society started deforestation, their findings shouldn’t be used as a justification for modern deforestation and destruction of the Amazon basin.