Lithics, landscapes & la Longue-durée – Curation & expediency as expressions of forager mobility

With the recognition that practically all archaeological sites are depositional composites unrelated to the activities of any contemporaneous group of individuals (i.e., palimpsests) and that forager adaptations are not ‘site-specific’ but rather landscape-scaled phenomena, statistical approaches designed to take these predicates into account have been developed over the past 20 years that depart from the traditional techno-typological systematics used for decades in much of Europe and the Levant. Based on artifact density and the frequency of retouched pieces scaled to the volume of sediment excavated in cave and rock shelter sites, and – for surface sites – the ratio of retouched artifacts to artifact totals scaled to unit area, they can potentially determine whether or not changes in mobility and land-use often assumed to have coincided with major evolutionary events (e.g., the Middle-Upper Paleolithic transition) actually occurred. Lithic artifact counts and densities from the cave of La Riera (Posada de Llanes, Asturias, Spain) are used here to illustrate the potential of the approach. Changes in artifact volumetric density are then compared with a radiocarbon summed probability curve using calibrated BP dates scaled against changes in oxygen isotope ratios in the GISP2 ice core. The intent is to determine to what extent macroclimatic change over the 30–10 ka cal BP interval compares with changes in the La Riera sequence.