It is not often that we gain insight into the cognitive functions of our forebears. A very rare type of tool made from a hippopotamus bone has been discovered at the Konso Formation in southern Ethiopia.
This artifact represents a technological breakthrough achieved 1.75 million years ago. Bone is tricky to shape and requires considerable judgment and skill to form successfully. Sano et al. show how this large (>10 centimeter) fragment was intentionally shaped by a controlled knapping technique and turned into a handaxe.
This breakthrough represents a step-change from the conservative thinking of previous tool makers. By analyzing the scarring around the edges of the superbly preserved tool, the authors inferred that the maker, probably Homo erectus, was able to adjust the thickness on both sides of the material by a distinctive flaking technique. This allowed it to be used for precise purposes, such as butchering animal carcasses.
Proc. Natl. Acad. Sci. U.S.A. 10.1073/pnas.2006370117 (2020).
