Discovery of 1.5 Million-Year-Old Bone Tools in Tanzania Rewrite Early Human History

Scientists have discovered the oldest known bone tools in Tanzania, made by early humans, dating back 1.5 million years. The findings challenge previous theories about when humans began using bone for tool-making, suggesting early ancestors were more resourceful than previously believed.

The tools, made from the leg bones of elephants and hippos, were unearthed at Olduvai Gorge, a key archaeological site in Tanzania. These artifacts are at least one million years older than any previously known shaped bone tools, researchers reported in the journal Nature on March 5.

Evidence of advanced skills

Researchers analyzed 27 bone fragments and determined they were deliberately shaped using a technique similar to stone tool-making. This method, called knapping, involves striking one object against another to break off sharp edges.

Stone tools shaped this way have been found in East Africa, dating back 3.3 million years. However, bone tools produced using the same method are rare. Scientists believe most have likely decayed over time, making this discovery especially significant.

The hominins “knew how to incorporate technical innovations by adapting their knowledge of stone work to the manipulation of bone remains,” said Ignacio de la Torre, an archaeologist with the Spanish National Research Council and lead author of the study.

A stunning find in Tanzania has revealed that ancient humans were routinely shaping and using bone tools 1.5 million years ago, a million years earlier than previously thought. This collection of artifacts, uncovered by archaeologists and announced on March 06, 2025 by @Nature,… pic.twitter.com/PwDo3TzCzG

— City Mirror (@citymirrorKE) March 6, 2025

Researchers confirmed through microscopic analysis that natural processes or animal bites did not make the bone markings but were the result of intentional shaping by human ancestors.

Strategic selection of materials

Scientists identified that the tools were made from specific types of bones: eight were crafted from elephants, six from hippos, and two from a cow-like species. Most other bones found at the site belonged to bovids, yet early humans appeared to have selectively chosen elephant and hippo bones.

The reason may be their size and strength. Elephant bone tools measured between 8.6 and 15 inches (22 to 38 cm), while hippo bone tools were slightly smaller, ranging from 7 to 11.8 inches (18 to 30 cm). Researchers believe these tools were used for heavy-duty tasks such as processing animal carcasses.

“It means that human ancestors were capable of transferring skills from stone to bone, a level of complex cognition that we haven’t seen elsewhere for another million years,” said Renata Peters, an archaeologist at University College London and co-author of the study.

Implications for human evolution

The findings challenge long-held assumptions about early human tool use. Previously, scientists believed that early hominins primarily relied on stone tools before later adapting to bone. This discovery suggests that early humans may have experimented with bone much earlier.

The exact species responsible for making these tools remains uncertain. Two early human species—Homo erectus and Paranthropus boisei—inhabited Olduvai Gorge 1.5 million years ago. Both were skilled tool users, but their specific roles in crafting these bone tools remain unclear.

This discovery not only reshapes the timeline of early human technology but also raises new questions about our ancestors’ cognitive abilities. Scientists say the findings open the door for further research into how early humans used different materials to survive and innovate.