This paper summarizes the results of the research carried out during a decade at the Hornillos 2 rockshelter, located at 4020 m asl in the Dry Puna of Argentina. The human occupations in this site are bracketed between the Pleistocene–Holocene boundary and the mid-Holocene, challenging the idea of a widespread abandonment of the Andes highlands during mid-Holocene due to extreme arid conditions (i.e. the “silencio arqueológico” or archaeological silence hypothesis). Nine occupational levels have been recognized in the timed span at the site, the result of hunter–gatherer activities carried out in a highly oscillating and changing environment.
Here we present the mean trends and patterns observed in the full set of lines of inquiry applied in the site: lithic evidence, zooarchaeological analysis, rock art, stratigraphic and spatial analysis, and isotopic data. The outcomes of these studies, together with the site location features, known raw materials sources and regional archaeological evidence, indicate that hunter–gatherer groups reduced their residential mobility, and increased the intensity of their occupations and the rate of technological innovations in the arid and unstable mid-Holocene landscapes.