A collection of bone implements, unearthed from a singular stratum dating back 1.5 million years at Olduvai Gorge in Tanzania, has been meticulously documented by paleoanthropologists. This assemblage predates other verifiable instances of deliberate bone tool manufacture by over a millennium, offering unprecedented insights into the largely uncharted domain of early hominin bone technology.
The 1.5-million-year-old elephant humerus that has been knapped into a tool. Image credit: CSIC.
Prior to this significant finding, evidence suggested that early hominins had been crafting tools from stone for at least a million years, yet tangible proof of systematic bone tool production only emerged around 500,000 years ago.
The hominins responsible for shaping these newly discovered bone implements employed techniques analogous to those used for stone tool manufacture, specifically the removal of small fragments to fashion sharp edges—a process known as knapping.
This transference of manufacturing methodologies across different materials underscores a sophisticated understanding of tool-making capabilities among these early hominins, demonstrating their adeptness at adapting established techniques to novel substances, marking a substantial cognitive advancement.
Such innovation may signify that our human ancestors at this epoch possessed a more developed cognitive capacity and brain development than previously posited by scientific consensus.
“This revelation compels us to infer that early humans considerably broadened their technological horizons, which at that juncture were primarily confined to the creation of stone tools, thereby enabling the integration of new raw materials into their repertoire of potential artifacts,” stated Dr. Ignacio de la Torre, a researcher affiliated with the CSIC-Spanish National Research Council.
“Concurrently, this expansion of technological potential points towards advancements in the cognitive aptitudes and mental frameworks of these hominins, who demonstrated an ability to assimilate technical innovations by applying their expertise in stone working to the manipulation of osseous remains.”
“The artifacts display indicators that their artisans meticulously worked the bones, dislodging flakes to achieve functional forms,” commented Dr. Renata Peters, a researcher associated with University College London.
“The discovery of these bone tools from such an ancient period was profoundly exciting.”
“It implies that our human forebears were competent in transferring skills honed on stone to bone, indicative of a level of complex cognition that has not been observed elsewhere for another million years.”
The bone tools, estimated to be 1.5 million years old, were unearthed at the T69 Complex site, specifically within the Frida Leakey Korongo West Gully at Olduvai Gorge in northern Tanzania—a locale celebrated for its rich archaeological history pertinent to understanding human origins.
The study’s authors identified a compilation of 27 bones that had been fashioned into tools at the excavation site. The skeletal material primarily originated from large fauna, notably elephants and hippos.
These implements were exclusively fashioned from the limb bones of the animals, selected for their inherent density and robust structural integrity.
The earliest known stone tools belong to the Oldowan epoch, which spanned roughly from 2.7 million to 1.5 million years ago. This era is characterized by a rudimentary method of stone tool fabrication, involving the detachment of one or more flakes from a stone core using a hammerstone.
The bone tools brought to light in the present investigation date to a period when ancient human ancestors were transitioning into the Acheulean epoch, which commenced approximately 1.7 million years ago.
A hallmark of Acheulean technology is the utilization of more elaborate handaxes, meticulously shaped through the knapping process, which facilitated the production of tools via more standardized procedures.
The bone tools provide evidence that these more sophisticated manufacturing techniques were successfully adapted and employed for working with bone as well, a development that had not been previously documented in the fossil record for another million years, occurring much later within the Acheulean period.
Prior to this groundbreaking discovery, osseous material fashioned into tools had only been identified sporadically in rare, isolated instances within the fossil record, and never in a manner that suggested systematic production by human ancestors.
While the precise function of these tools remains undetermined, their general configuration, dimensions, and sharp edges suggest a probable application in the butchery of animal carcasses for sustenance.
Furthermore, the specific species of human ancestor responsible for their creation remains indeterminate.
No hominin skeletal remains were discovered in proximity to the collection of bone artifacts; however, historical data indicates that Homo erectus and Paranthropus boisei were contemporaneous inhabitants of the region.
“Given that these tools represent such an unanticipated discovery, we aspire that our findings will encourage archaeologists to meticulously re-examine bone assemblages globally, in the event that other evidence of bone tool manufacture has been overlooked,” the research team stated.
Their report is published today in the esteemed journal Nature.
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I. de la Torre et al. Systematic bone tool production at 1.5 million years ago. Nature, published online March 5, 2025; doi: 10.1038/s41586-025-08652-5
