3.3-Million-Year-Old Stone Tools and Butchery Traces? More Evidence Needed

Abstract

In the past five years, two exceptional discoveries have been made—the Dikika modified bones and the Lomekwi stone tools. If genuine, they would change current views on human evolution by showing that Pliocene hominins were involved in stone tool use and meat-eating more than 3 million years ago. These paradigm-changing discov-eries require solid, unambiguous evidence. Here, we adopt a hypothesis-testing scientific approach in which we show that neither of these discoveries, as reported, has provided compelling evidence of these behaviors in the Pliocene. We do not reject the hypothesis of stone tool use and butchery in the Pliocene. We do however stress that the evidence presented in both cases remains disputable and the inferences drawn from it are not secure. We argue that the hypotheses of non-hominin agency for the Dikika bones and the ex situ nature of the Lomekwi assemblage (probably involving a palimpsest of accumulations) have not been discarded.