Pre-hispanic agriculture in northeast argentina analysed through stable isotopes

Abstract

Through the analysis of the isotopic values of the diets (d13Ccollagen, d13Capatite, d13C and d15N), and discriminant functions based on them, the impact of agricultural practices in different archaeological units of the northeast of Argentina is analysed. The results show a moderate consumption of maize in the individuals recovered in the Itararé-Taquara sites of the province of Misiones, as well as in the samples from the Guarani sites of the latter province and of Buenos Aires. Among complex hunter-gatherers of the middle and lower the Paraná River (Entre Ríos and Buenos Aires provinces), maize was not detected at the population level, while the consumption of C3 plants was highly variable. In those individuals recovered from sites traditionally defined as Goya-Malabrigo, the diets had a very small component of C3 plants, some of which could eventually be cultivated; however, their incidence in the diet was absolutely marginal. In individuals from the Plain Pottery Cluster, maize consumption is also undetectable in population terms, although a few individuals show a slight enrichment in bioapatite related to a lower consumption of C4 resources. However, it is not certain that this corresponds to the intake of maize. The C3 plant component among these individuals is higher in relation to those from the Goya-Malabrigo sites, reflecting the consumption of wild plants and eventually, a small fraction that could have been cultivated. Finally, the samples from the Incised Pottery Cluster present the highest intake of C3 plants of all the local pre-Columbian populations, which could
be both wild and cultivated. This group also includes an individual with isotopic signals indistinguishable from moderate consumption of maize and indeterminate C3 plants, whose direct dating of 1360 ± 70 years 14C BP, would indicate the oldest effective incorporation of this cereal into the diet.