Getting into shape: computing continua of Middle Stone Age prepared core technology

Levallois technology is a particularly skilful and cognitively intensive lithic technology where preparatory core shaping is aimed at producing predetermined flake blanks. It has significant implications for hominin evolution and dispersals, yet remains notoriously difficult to define relative to other prepared cores. Significant variability in prepared core techno-morphology is often rendered into a handful of rarely agreed upon discrete categories. We ask whether existing classifications of cores are immutable, discrete groups, or whether there are unbroken continua of prepared core variability. With a bespoke set of 3D computational methods, we directly quantify the criteria used to define Levallois technology. Applied to a diverse sample of prepared cores from five African MSA sites, these methods establish continua of prepared core preparation, recurrence and exhaustion. Quantifying this continuous variability in how blanks are removed from cores can help holistically address past hominin technological decision making, investment and flexibility.