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Indigenous people had intense impact on Amazon rainforests: Study
Amazon’s ancient indigenous people had a far more intense impact on the composition of the vast local rainforests than formerly known, a new study has suggested.
The new research suggested that several tree species in the Amazon region are abundant because they were cultivated by indigenous people who populated the region before Europeans’ arrival more than 500 years ago.
These tree species include the Brazil nut, acai palm, cacao, caimito and tucuma palm, rubber and cashew.
Study researcher Hans ter Steege said, “So the Amazon is not nearly as untouched as it may seem … Past civilizations have had a great role in changing, both consciously and unconsciously, the vegetation in the surroundings of their settlements and along paths that they used to travel.”
Hans ter Steege is a forest community ecologist at the Netherlands-based Naturalis Biodiversity Center and Free University of Amsterdam.
The researchers reached the conclusion after analyzing trees at nearly 1,170 sites across the Amazon and compared the data to a map of over 3,000 known archaeological sites representing former human settlements in the region.
The researchers detailed their findings in the most recent edition of the journal Science.
The research team informed, "To see whether humans had a hand in this dominance, the team checked the abundance and richness of trees around places with no evidence of past occupation and also near 3348 archaeological sites, such as rock art or earthen mounds. Common domesticated species, such as the Brazil nut tree, were more abundant near places where people once lived. The richness and abundance was particularly striking in the eastern and southwestern Amazon. In parts of the Amazonian forest within Bolivia, for example, domesticated species accounted for up to 61% of tree diversity."
A report published by smithsonian Magazine informed, "The researchers also found that many of these domesticated species were identified far from the areas where they first arose, leading to speculation that humans transported them to cultivate elsewhere. Cocoa, used by some native peoples for beverages and in religious ceremonies, was first domesticated in the northwestern region of the Amazon, where researchers today have identified a larger genetic diversity reflecting more time established there. But today the species is most prevalent in the southern areas of the rainforest."
“I was actually a bit stunned,” Ter Steege says. “The effect of Pre-Columbian people is much more pronounced than many of us believed.”