New Evidence of Grinding Activities in Patagonian Steppe during the Late Holocene (ca. 2000 Years BP): The Laguna Azul Site (Somuncurá Plateau, Río Negro Province, Argentina)

Abstract

This paper aims to present the first record of micro vegetable remains in grinding-stone tools found in hunter-gatherer contexts located in Laguna Azul (Somuncurá plateau, Argentina). These grinding-stone tools resulted from excavations of two hunting blinds (known as “parapets”) related to late Holocene radiocarbon dates of 1756 ± 28 years BP (D-007084; δ 13C = 20.2‰) and 1906 ± 26 years BP (D-007085; δ 13C = −19.8‰). The combination of micro-wear and starch grains studies allows us to discuss the autochthonous and allochthonous vegetation processing activities. From these remains, four types of vegetation with nutritive potential were identified: Chenopodaceas, Amaranthaceas, Prosopis sp. and Araucaria sp. The grinding stone tools’ microscopic analysis gave evidence of the specific processing motions employed. This evidence-based data enables us to discuss the relationship between the hunter-gatherers and their environment during the late Holocene and also to establish new assumptions about circuits of mobility and communication.