Were early humans more intelligent than we thought? A recent study has uncovered 27 bone tools in Tanzania, revealing that early humans adapted stone-shaping techniques for bone as early as 1.5 million years ago — rewriting the history of technological evolution.
The study, published in the journal Nature, claimed that this discovery challenges our understanding of early hominin technological evolution.
Early human ancestors known as hominins, the group that includes modern humans, extinct human species and their immediate ancestors — such as Homo, Australopithecus, Paranthropus and Ardipithecus — had been making stone tools for at least a million years. However, evidence of widespread bone tool production before 500,000 years ago has been scarce.
Early humans employed a technique known as knapping, traditionally used for shaping stone tools in the Stone Age, to fashion bone implements, the paper suggested. This indicates that East African hominins adapted stone knapping skills for use with bone.
“These tools challenge our understanding of cultural evolution in our lineage. Until now, we thought that the use of bone as tools was rather rare, episodic and expedient,” Luc Doyon, Lecturer and Researcher at University of Bordeaux, told Down To Earth.
The 27 specimens indicated a recurring pattern in the selection, modification and use of large mammal long bones, suggesting the social transmission of technological knowledge. “The importation of some specimens made of elephant bones also suggests some level of planning depth that was unsuspected for bone technology,” Doyon said.
This transfer of techniques from stone to bone implies that hominins possessed greater cognitive abilities and brain development than previously thought.
The bone tools were unearthed in Tanzania’s Olduvai Gorge, one of Africa’s most famous palaeoanthropological sites, renowned for high-profile hominin fossil discoveries. The site is considered an ideal place for studying the biological and cultural emergence of the Homo genus and its environmental context.
The tools were found at an archaeological site known as the T69 Complex, within the Olduvai Gorge in northern Tanzania. Researchers excavated seven trenches between 2015 and 2022.
“Our discovery indicates that from the Acheulean period [1.6 million to 200,000 years ago], in which the T69 Complex site was formed and where humans already had a primary access to meaty resources, no longer were animals only dangerous, competitors or just foodstuff, but also a source of raw materials for producing tools,” said Ignacio de la Torre, scientist at CSIC-Instituto de Historia and co-author of the study, in a statement.
The researchers have not been able to confirm human settlement in the area at the time. “Traces of settlement are difficult to distinguish at that age. What we can say is that the site was mostly visited to access and process carcasses of bovids and hippopotamus. Indeed, there are clear butchery marks on many bones recovered in the archaeological layer,” Doyon explained.
The species responsible for crafting these bone tools remains uncertain, as no hominin remains were found at the site. However, researchers speculate that Homo erectus or Paranthropus boisei, both of which inhabited the region at the time, may have been responsible for the innovation.