PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES—A 1.4-million-year-old handaxe made from hippopotamus bone expands the known technological repertoire of early human ancestors, according to a study*. During the Pleistocene, Homo species developed handaxes from stone and, occasionally, bone, a tool production style known as the Acheulean. Gen Suwa and colleagues report a rare handaxe made from bone in the Konso Formation, showing that the advanced flaking techniques used on lithic materials were also practiced on bone by early Homo species living in southern Ethiopia. The 13-cm-long bone was recovered from strata dating to 1.4 million years ago. The authors characterized the bone, noting that it retained the surface of an original hippopotamus femur on the dorsal side and exhibited extensive flake scars. Analysis of the flake scars showed that the scars are continuous and that those near the handaxe’s tip appear in an alternate pattern, suggesting deliberate shaping of the bone. The authors also analyzed wear on the handaxe, finding macroscopic rounding near the tip and on both faces, suggesting cutting and sawing activities. Microscopic analysis of the handaxe revealed areas of polish and striation patterns similar to stone tools used for butchery. Given the small number of bone tools unearthed and a dearth of knowledge about bone polish patterns, the nature of the materials on which the rare bone handaxe was used remains unclear, according to the authors.
