The results of isotopic analysis of 23 Precolumbian complex hunter-gatherers recovered in the lower Parana wetland (Argentina, South America) are presented.

Two isotopic trends were identified. The first one is based on depleted proteins with high trophic levels, related with freshwater fish consumption. The second one is similar, but includes a moderate intake of carbohydrates.

The regional tendency was focused on fishing resources over time, and not in an alleged importance of cultigens

No maize intake was isotopically detected

Data obtained in infants and children suggest an early period of weaning and age-based food allocation for infants, based on depleted carbs