Ancient Worlds

15
Jul

Ancient Amazonians Were Deft Environmental Engineers

It’s hard to imagine what Brazil or Bolivia would be like without the Amazon.

That’s why archaeologists have long assumed that early indigenous South Americans lived in openings they created in the lush rainforest. It would have been a gargantuan task, achieved either with axes or fire. Now, though, evidence from a series of ringlike ditches scattered throughout the area suggest that human activity came before the forest even existed.

savannah-Bolivia
The ancient Amazon once looked more like this savannah in modern day Bolivia than the rainforest we know today.

Here’s Stephanie Pappas, writing for LiveScience:

These human-made structures remain a mystery: They may have been used for defense, drainage, or perhaps ceremonial or religious reasons. But the new research addresses another burning question: whether and how much prehistoric people altered the landscape in the Amazon before the arrival of Europeans.

“People have been affecting the global climate system through land use for not just the past 200 to 300 years, but for thousands of years,” said study author John Francis Carson, a postdoctoral researcher at the University of Reading in the United Kingdom.

The Amazon had once been a more open savannah, more similar to the Serengeti in African than today’s lush forest before the climate turned wetter some 2,000 years ago. But the land around the earthworks remained open. Previous hypotheses suggested that Amazonians had logged those areas using stone tools to keep them clear.

But Carson and his colleagues say pollen records suggest that Amazonians simply maintained the open savannah around the earthworks. This would have been far simpler on one hand—logging with stone axes is strenuous work—but in other ways more complicated—Amazonians had to maintain these patches over hundreds of years, which would have required substantial coordination and planning.