The rainforest only began to spread in around 0-300AD, as the climate changed and became more wet.
To many people, the Amazon rainforest shows nature’s true majesty, just what nature is capable of without human intervention. From its rich biodiversity to its sheer scale, the Amazon is truly a natural wonder. However, new research shows that it may not always have been like this. In a study published in the Proceedings of the National Academy of Sciences (PNAS), researchers from the University of Reading say that large swathes of what is now rainforest may once have been grasslands.
The researchers took samples known as “mud cores” from two sites in Bolivia. These samples were then analysed, and found to contain pollen and other particles which shows a change in the area’s ecosystem over the past 6000 years.
The research team were attempting to find evidence of which kind of crops the ancient Amerindian peoples grew, and how much impact they had on the forest. This research suggests that the people of the Amazon did not clear parts of the forest as was previously suggested, but grew crops in what was at the time an open landscape. The rainforest only began to spread in around 0-300AD, as the climate changed and became more wet.
Evidence suggests that after the climate change the native peoples kept the area open for farming purposes, and prevented the spread of the jungle. He says that this continued until the European discovery and subsequent invasion of South America. Following the European colonization, a large proportion of the Amerindian population perished, either due to disease or at the hands of the colonizers. After this, the jungle took over the areas kept clear.
Dr John Carson, the lead researcher on the study, says that the team’s findings could be very useful for understanding climate change, as well as what could happen if the widespread deforestation of the Amazon continues.
“It suggests that Amazonia was neither pristine wilderness, nor has it shown resilience to large-scale deforestation by humans in the past.”