Far from being pristine wilderness, some parts of the Amazon have been deeply altered by humans dating back 10,000 years, the researchers say.
An international team found that during this period, crops were grown in a location far from what is now northern Bolivia.
Scientists believe that the humans who lived here planted squash, cassava and corn.
Residents have also created thousands of artificial islands in the forest.
The end of the last ice age, about 12,000 years ago, saw a sustained increase in global temperatures that caused many changes in the world.
Perhaps the most important of these is that the earliest civilizations began to abandon the life of hunter-gatherers and to start cultivating for food.
Researchers previously uncovered evidence that the crops were domesticated at four important locations around the world.
Thus, China saw the cultivation of rice, while in the Middle East it was cereals, in Central America and Mexico it was corn, while potatoes and quinoa emerged in the Andes.
Scientists today say that the Llanos de Moxos region in southwest Amazon should be considered a fifth key region.
The area is a savannah, but is dotted with raised land now covered with trees.
The area is flooded part of the year, but these “forest islands” remain above the water.
Some 4,700 of these small mounds have been developed by humans over time, in very ordinary ways.
“These are just places where people have dumped their garbage and over time they grow up,” said Dr. Umberto Lombardo, lead author at the University of Bern in Switzerland.
“Of course, garbage is very rich in nutrients, and as these areas grow, they exceed the level of flooding during the rainy season, so they become good places to settle with fertile soil , so people keep coming back to the same places all the time. “
Researchers examined around 30 of these islands for evidence of planting crops.
They discovered tiny fragments of silica called phytoliths, described as tiny pieces of glass that form inside plant cells.
The shape of these tiny glass fragments is different depending on the plants from which they come.
Researchers were able to identify evidence of cassava (cassava, yuca) grown 10,350 years ago. Squash appeared 10,250 years ago, and corn more recently – only 6,850 years ago.
“It’s pretty surprising,” said Dr. Lombardo.
“It’s the Amazon, it’s one of those places that we thought a few years ago was like a virgin forest, an intact environment. “
“Now we find this proof that people lived there 10,500 years ago, and they started to practice cultivation. “
People who lived at that time probably survived the sweet potato and peanuts, as well as the fish and large herbivores.
Researchers say it is likely that the humans who lived here brought their plants with them.
They believe their study is another example of the global impact of environmental changes that are being felt as the world warmed at the end of the last ice age.
“This is interesting because it again confirms that domestication begins at the start of the Holocene period, when we experience this climate change that we see at the end of the ice age,” said Dr. Lombardo.
“We have entered this hot period, where all over the world at the same time, people are starting to cultivate. “
The study was published in the journal Nature.
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