Isotopic evidence of diet breadth hunter‐gatherers changes during the Holocene in the Central Pampean Dunefields (Argentina, South America)

Abstract

Objectives: Based on the analysis of stable carbon and nitrogen isotopes of bone collagen,stable carbon isotopes of bone apatite and an extensive AMS dating series(10,000–299 years cal BP), the human paleodiets of 34 individuals from the CentralPampean Dunefields (Argentina, South America) are evaluated.Materials and Methods: These data are interpreted from the isotopic ecology of animalswith archaeofaunal evidence of consumption and isotopic models of humandiet. Multivariate carbon and nitrogen stable isotope model and Bayesian stable isotopeellipses were used to interpret human diets.Results: Analysis of isotopic values indicates intake of enriched lipids and/or carbohydratesin relation to the proteins consumed throughout the Holocene. The isotopicvalues of Middle Holocene humans in relation to the values of exploited resourcespoint out that individuals obtained protein mainly from guanaco. Subsequently, therewas an increase in the human breadth diet during the Late Holocene, with a greaterrelevance of small prey of high trophic levels and vegetables. This contrasts withzooarchaeological information indicating generalist human diets during the MiddleHolocene and specialized human diets in guanaco during the Late Holocene.Conclusions: It is proposed that during the Middle Holocene arid period, the combinationof low human population density and high residential mobility in wide foragingranges allowed the guanaco to be the main source of protein. During the Late Holocenehumid period, there was an increase in human population density and adecrease in residential mobility, which caused greater pressure on foraging territoriesand increased dietary breadth.