New chronostratigraphic records of the early-to-middle Holocene in the north-central region of Chile indicate Andean foothills housed hunter-gatherers during pulses of extreme aridity

Abstract

The scarcity of middle Holocene radiocarbon dates in different regions of the Andes has been interpreted as an indicator of discontinuity in human occupations in response to adverse environmental conditions due to marked aridity. In the subtropical Andes of north-central Chile and adjacent areas, this paucity has been detected in radiocarbon ages between 8000 and 6000 cal BP. A systematic programme of cave excavations with detailed chronologies in the Combarbalá area in the Andean western foothills at 31°S allows questioning the role these spaces and ecosystems played for hunter-gatherers throughout the Holocene. The elusive record of dateable material has been addressed by excavating deposits under rock-shelters which tend to trap sedimentary material. This dataset has been compared with the available climate records and shows a collation between the onset of various site chronologies during the early-to-middle Holocene and periods of extreme aridity. The organization of mobility and the role of Andean foothills for hunter-gatherer settlements is reviewed. Resource availability in the area, namely fresh water supply, good-quality toolstones, faunal resources, and shelters, attracted mobile populations to these environments as indicated by our records as well as others in the broader region.