The Guaraní expansion through the Lowlands of South America

Abstract

This study examines the expansion of Amazonian forager-horticulturalists grouped within the Guaraní archaeological unit,who migrated from southwestern Amazonia to southeastern South America, spanning much of the La Plata basin and theAtlantic coastal slope of southeastern Brazil, covering over 2500 km in a relatively short period. This process, marked byrapid expansion and extensive territorial coverage, represents one of the most remarkable migrations recorded among knownpre-industrial societies. The initial expansion probably began in southwestern Amazonia, progressing southeastward to theheadwaters of the La Plata basin, where this population appears as a weak archaeological signal around 500 CE. Approximately 800 years later, these Amazonian groups reached the Río de la Plata estuary, 1400 km farther south. Based on calibrated age ranges, the spatial distribution of Guaraní sites across the basin, and the application of various statistical methods(Silhouette Coefcient Analysis, Hierarchical Cluster Analysis, Principal Components Analysis, and Summed ProbabilityDistribution of radiocarbon ages), this expansion was divided into four clusters or phases, refecting a complex migratoryprocess. In addition to redefning the dynamics of Guaraní expansion, this study provides a better alignment with linguisticdispersion models of these populations and ofers new perspectives on how canoeing societies, in general, can rapidly spreadacross a vast territory within a brief archaeological timeframe.