We Called It Wilderness
What LiDAR revealed in the Amazon
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Amazon rainforest canopy in Acre, Brazil. Photograph by Guilherme Noronha/Embrapa Acre.
For centuries, the forest was presented as evidence that no civilisation had been there. This week, we learned that the evidence had been growing over it.
A study appeared in Nature on Wednesday.
A team led by Martti Pärssinen, who has spent more than two decades working in the Brazilian state of Acre, flew ten long airborne LiDAR transects across nearly 4,500 square kilometres of rainforest, sending pulses of laser light down through the gaps in the canopy until the ground beneath the trees gave up its shape.
What came back was a drawing of 432 monumental earthworks, of which only 36 had ever been recorded. The other 396 were new to science: circles, squares, octagons, ceremonial enclosures cut into the earth with ditches up to five metres deep, the excavated soil raised into banks beside them, roads running between centres, the whole apparatus of societies that gathered, deliberated and celebrated. Extrapolated across the cultural region the researchers call Aquiry, an area of roughly 183,000 square kilometres reaching into present-day Bolivia and Peru, an area roughly comparable to modern Syria, the count rises to somewhere between twenty-four and thirty thousand structures, built and maintained across nearly fifteen centuries by a population that at its height, around the second and third centuries of our era, may have numbered between one and a quarter and three million people.
As many as three million people, and we called it wilderness.
