Hominins have been making and using stone tools since at least 3.4 Ma, as shown by cut marks on bones and stone artefacts themselves. I use the sack term ‘hominin’ because the likely makers and users of the oldest tools are either australopithecines or paranthropoids, there being no fossils designates to the genus Homo of late-Pliocene age. So it might seem un-newsworthy to report that the oldest tools deliberately made from bone are now known to occur in 1.5 Ma old sediments from the famous sedimentary sequence at Olduvai Gorge in Tanzania (de la Torre, I and 8 others2025. Systematic bone tool production at 1.5 million years ago. Nature, v. 639; DOI: 10.1038/s41586-025-08652-5). To be clear, there is abundant evidence that hominins had used bones, especially sturdy long bones, for digging perhaps, much earlier in hominin history. Again, paranthropoids have been implicated in their use. The bones found at Olduvai actually show signs of manufacture into useful objects prior to their use: they show clear signs of knapping to produce points and blades. The bones are among the sturdiest known from the Pleistocene, being from elephants and hippos. Before de la Torre and colleagues found what is essentially a bone-tool factory, it was thought that systematic use of bones in such a sophisticated manner only arose between 400 to 250 ka ago among early Homo in Europe. Sadly, fossils of whoever made the tools were not found at the site. Once again, paranthropoids as well as early Homo are known to have cohabited the area at that time.

Bifacial Acheulean stone artefacts first appear in the rock record about 300 ka before these bone tools were made. So one idea that the authors put forward is that the same kind of stone knapping technique was transferred to the more abundant massive bones of the East African Pleistocene megafauna (in the absence or rarity of suitable blocks of stone?). But it remains unclear whether or not such tools were simply selected from very large bones smashed to get at their nutritious marrow. The first possibility implies a cultural shift, whereas the latter points simply to expedience. The authors are at pains to point out that the curious million-year gap in the record of bone tools may be ascribed either to the disappearance of bone technology or simply to archaeologists who worked elsewhere having not regarding bone fragments as the products of skills. That applies equally to earlier times, when bones were indeed used, though with not so much in the way of a ‘mental template’. As de la Torre et al. conclude ‘Future research needs to investigate whether similar bone tools were already produced in earlier times, persisted during the Acheulean and eventually evolved into Middle Pleistocene bone bifaces similar in shape, size and technology to their stone counterparts’.

