Sizable parts of the Amazon basin may have looked more like the open savannah seen in Africa than the rainforest we know today.
A team of researchers from the University of Reading have discovered strong evidence of farming communities built before the arrival of Europeans in South America.
The team dug out mud cores at different depths in a remote part of Bolivia. The mud cores were dug from the bottom of two lakes close to ancient earthwork structures. What they found was stunning.
Evidence points that the people of the Amazon were not rainforest hunter-gatherers. From 2,500 to 500 years ago, these people were farmers who used naturally open landscape to grow food and build major earthworks.
Large amounts of grass pollen in the ancient sediments point to an environment more like a savannah than a rainforest.
So, what explains the drastic changes in the region? Climate change. The area became wetter sometime between 0-300 AD and started pushing the rainforest south. The people in the settlements worked to keep the forest at bay as they kept farming. The rainforest would eventually win, though. Once Europeans discovered South America, disease spread from them and decimated the local population.
“These results were very surprising. We went to Bolivia hoping to find evidence of the kinds of crops being grown by ancient Amerindian groups, and to try to find how much impact they had on the ancient forest. What we found was that they were having virtually no effect on the forest, in terms of past deforestation, because it didn’t exist there until much later,” said Dr. John Carson, a paleoecologist at the University of Reading who led the study.
Carson added, “Our findings have serious implications for understanding past climate change, and how the Amazon basin might react to more modern forest clearance. It suggests that Amazonia was neither pristine wilderness, nor has it shown resilience to large-scale deforestation by humans in the past.”
Carson and his team’s findings were published in the Proceedings of the National Academy of Sciences.