A feline tooth buried in the Cerrado tells you almost nothing about maize. That’s the point. When Eliane Chim and her colleagues needed a baseline against which to measure human diets, they turned to deer, peccaries, lizards, anteaters, the ordinary residents of the savanna who never touched a cultivated field. Their bone collagen clustered tightly around a diet built on native C3 plants, the grasses and shrubs and fruits that have always structured life in this biome. Against that baseline, human bones and teeth from 37 archaeological sites told a much stranger story. Some individuals looked just like the fauna around them. Others were so enriched in carbon-13 that their tissue chemistry pointed almost entirely at one plant: maize.
That contrast is the whole argument of a new paper in Science Advances,1 and it lands in the middle of a real disagreement. A widely discussed 2025 study of the southwestern Amazon argued for something close to maize monoculture, an intensive, irrigation-supported farming system underwriting urban-scale precolonial settlements. The Cerrado data push back against that framing, not by denying maize’s importance but by showing what “importance” actually looked like on the ground: heavy reliance on maize, yes, embedded within a much broader and more diversified system of food production.
