More than 1,000 years ago, people living in Brazil's tropical savanna built large villages and grew maize—but not the way modern industrial farms do. Instead of planting single crops over huge areas, these ancient communities mixed maize with other plants, creating diverse farms that fed whole settlements while keeping the land healthy. A new study published in Science Advances shows just how clever these farmers really were.
For a long time, scientists debated how people in the Brazilian Cerrado—a vast tropical savanna—lived before European colonizers arrived. Were they wanderers who hunted and gathered food? Or settled farmers who grew crops? The answer, it turns out, is more interesting than either option.
Researchers from the Max Planck Institute of Geoanthropology and the University of São Paulo analyzed more than 100 ancient skeletons from 37 different sites across Brazil. By studying chemical signatures in their teeth and bones, scientists could tell what foods these people ate. They found that people living in open villages got a large part of their calories from maize. But people living in nearby rock shelters at the same time ate much more varied diets with little maize. Since both groups lived in similar environments, the difference wasn't about what the land could grow—it was about different cultures making different choices.
The findings reveal something important: these ancient farmers didn't plant only corn, the way many farms do today. They practiced what scientists call polyculture—growing maize alongside other crops and wild plants. This mix kept the soil fertile, prevented pests, and could support bigger communities than monoculture (growing just one crop) ever could.
"Some societies depended heavily on maize grown within diversified agricultural systems capable of sustaining large villages," said Eliane Chim, the study's lead author. "This fundamentally changes our understanding of Indigenous food production and central Brazil."
André Strauss from the University of São Paulo said the Cerrado has been overlooked in favor of the Amazon when people talk about precolonial innovation. But this research shows the savanna was just as important. "Different societies developed distinct ways of interacting with one of the world's most biodiverse tropical landscapes," Strauss said.
Today, as farmers and scientists look for ways to grow food without destroying the environment, this ancient knowledge matters. The Cerrado is still one of Earth's most biodiverse regions, and these findings suggest that Indigenous land management helped shape it for centuries. The hope is that modern agriculture might learn something from the people who farmed there long before tractors and synthetic fertilizers existed.