Ancient indigenous peoples had a far more profound impact on the composition of the vast Amazon rain forest than previously known, according to a study showing how tree species domesticated by humans long ago still dominate big swaths of the wilderness.
Researchers said on Thursday many tree species populating the Amazon region appear to be abundant because they were cultivated by people who populated the area before Europeans arrived more than five centuries ago. These include the Brazil nut, cacao, acai palm, rubber, caimito, cashew and tucuma palm.
"So the Amazon is not nearly as untouched as it may seem," said study researcher Hans ter Steege, a forest community ecologist at the Naturalis Biodiversity Center in the Netherlands and Free University of Amsterdam.