Polyculture systems in the Brazilian Cerrado

An international team of researchers, including Dr Ricardo Fernandes from the UW Faculty of Archaeology, has shown that maize-based polyculture, rather than monoculture, formed the foundation of the livelihoods of pre-colonial communities in the Brazilian Cerrado. The findings were published in the journal Science Advances.

A team of researchers, including Dr Ricardo Fernandes, has shown that ancient indigenous communities inhabiting Brazil’s Cerrado biome (a tropical savanna region) practiced diverse and advanced agricultural systems, combining maize cultivation with other crops in polycultures rather than relying on a single crop.

The researchers described their findings in an article titled “Maize-based polyculture, not monoculture, sustained pre-colonial societies in the Brazilian Cerrado,” which was published in the journal Science Advances.

By analyzing the bones and teeth of 101 skeletons recovered from 37 archaeological sites dating to the Late Holocene across three Brazilian biomes—the Cerrado (Brazilian savanna), the Caatinga (dry forest), and the Atlantic Forest (a region of lush forests) in east-central South America, researchers reconstructed ancient diets. Carbon and nitrogen isotope analysis revealed the types of foods consumed by the inhabitants of these regions. The study also incorporated modern faunal reference data and radiocarbon dating results.

The results show cultural and economic diversity among archaeological traditions. Integrating archaeological, palaeoecological, and chronological data, we argue for the coexistence of a diversified and a more complex food production systems in the Cerrado biome, comparable to those of pre-colonial urban-scale populations practicing maize agriculture in the Amazon. These findings demonstrated that eastern South America populations practiced maize-based polyculture, reshaping current models of cultural and environmental dynamics in the Cerrado biome.

Advanced agricultural systems

The study found that two different lifestyles coexisted: people living in rock shelters (Una pottery tradition) had highly variable diets, while those in large open-air villages (Aratu pottery tradition) relied heavily on maize as a dietary staple, with the highest maize consumption of any group studied.

These findings challenge earlier assumptions that Cerrado peoples were mostly mobile hunter-gatherers who only occasionally farmed, showing instead that they were sophisticated farmers with permanent villages of hundreds of people. Notably, some villages continued using Aratu-style pottery even after European contact around 500 years ago, suggesting greater resilience than previously recognised.

The research highlights that Indigenous peoples have sustainably managed and shaped Cerrado ecosystems for thousands of years, and that these ancient agricultural systems, which maintained biodiversity while supporting large populations, offer valuable lessons for modern farming practices in the region.

“These findings completely reshape our understanding of pre-colonial life in the Brazilian Cerrado. We’re not looking at simple hunter-gatherers or early monoculture farmers, we’re seeing sophisticated, sustainable polyculture systems that supported large, permanent villages for centuries. The coexistence of such different dietary strategies among neighbouring groups at the same time shows us that ancient Indigenous peoples made deliberate cultural choices about how to manage their environment, and they did so in ways that maintained biodiversity for generations. This isn’t just ancient history, it’s a living lesson in sustainable food production that we can learn from today,” says Dr Ricardo Fernandes.