Use-wear analysis of lithic and bone artifacts coming from Guaraní archaeological assemblages from the Paraná River Basin, Argentina

•Horticulturalists groups occupied the Paraná Basin since at least 2000 years BP.•Technological studies were traditionally centered on pottery analysis.•Lithic and bone technology are analyzed through use-wear techniques.•Results show that Guaraní had a consistent and persistent lithic toolkit along the basin.•Bone technology was expedient, with no standardized tools. Although pottery technology has been extensively studied in Pre-hispanic horticulturalists groups from the Paraná River Basin (known as Guaraní), lithic and bone technology is still poorly understood. Frequently, archaeologists have centered the debate on pottery decoration and form, mainly to discuss migration routes, but also to establish certain aspects of the domestic life of such groups. Guaraní technology is only partially known, as there is scarce information regarding lithic and bone exploitation as raw materials. This paper focuses on lithic and bone use-wear analysis in order to discuss the technological choices of these groups. To this end, we analyzed the assemblages coming from Guaraní archaeological sites of two different areas in the Paraná River Basin: the low Paraná wetland, and the upper Paraná river. Both deposits have radiocarbon dates from the late Holocene (c. 700 BP), before the Spanish conquest of America, which reinforces the hypothesis that Guaraní groups arrived at the Río de la Plata area a few centuries before the Spanish conquerors. Results show that, despite environmental variability, similarities across technological solutions can be discerned. Although lithic technology shows variability in the raw materials employed as well as a diversity in stone tool classes, artifactual use in both areas is mainly associated with the processing of vegetables. For bone technology, similarities are marked by the absence of standardization associated with an expedient use of this raw material in both cases.