Resetting the null hypothesis: early stone tools and cultural transmission

We have learned much about tool use in non-humans since the first discovery of Oldowan stone tools. Despite the ongoing debate over whether tool use in other animals requires cultural transmission, it seems clear that today humans show a quantitative, if not qualitative, difference in our ability to transmit information socially through cultural transmission. This ability makes cumulative culture possible. Comparative studies provide relevant insights, however to address the when, where, and ultimately why this shift to high-fidelity social learning occurred we must look to the Paleolithic archaeological record. Yet here the de facto assumption that even the earliest stone tools serve as evidence of high-fidelity cultural transmission hinders investigation more than it helps. Here, we pragmatically suggest "resetting" the null hypothesis for the processes underlying early stone tool production. The null hypothesis we prefer is that Earlier Stone Age tools might have been so-called latent solutions rather than cultural material that derived from – and depended upon – modern human-like high-fidelity cultural transmission. This simple shift in perspective prioritizes the systematic investigation of more parsimonious potential explanations and forces us to demonstrate rather than presume that stone tools could not have existed without high-fidelity cultural transmission.