Hundreds of ancient earthworks have been discovered in the Amazon, which up until now, had been lost to nature over the years, and have only recently reclaimed by deforestation. The structures, described as ditched enclosures, are contained within an area roughly 13,000 km2 within the Brazilian rainforest. Hypotheses abound, from village borders to defensive erections, but they have all been ruled out, with archaeological digs in surrounding areas yielding little to no artifacts.
Academics from Brazil and the United Kingdom, working on a study set to be published Proceedings of the National Academy of Sciences, tried to decipher the meaning of the earthworks, but they have so far remained a mystery. However, the geoglyphs have provided more than just questions, with these structures suggesting that our knowledge of the Amazonian rainforest could be flawed. It has long been assumed and theorized that the gigantic forest that makes up most of Brazil could be a pristine ecosystem that has remained unchanged for thousands of years, but the 450 structures uncovered refute that premise.
This discovery encouraged researchers to use state-of-the-art technology to help reconstruct 6000 years of vegetation and fire history at two of the hundreds of sites to try gain a better understanding of how the area has changed since the geoglyphs were created. The process involved taking multiple soil samples around the structures and analyzing their composition, thus unveiling the rich history of the land. The researchers analyzed their results, and were able to determine that humans inhabiting these areas during that time engaged in agroforestry practices. This included clearing bamboo forests and making their own clearings in order to build these earthworks.
Whilst these findings have certainly added to our wealth of knowledge, it is also a silver-lining in the continuing deforestation of the Amazon, but the researchers responsible for the discoveries want to make sure that it doesn’t serve as a precedent for more logging. Per Dr Jennifer Watling:
“Our evidence that Amazonian forests have been managed by indigenous peoples long before European Contact should not be cited as justification for the destructive, unsustainable land-use practiced today. It should instead serve to highlight the ingenuity of past subsistence regimes that did not lead to forest degradation, and the importance of indigenous knowledge for finding more sustainable land-use alternatives”.