480,000-year-old ax sharpener is the oldest known elephant bone tool ever discovered in Europe

A triangular artifact crafted from elephant bone was used by archaic human relatives to sharpen hand axes around 480,000 years ago in what is now the U.K., a new analysis reveals.

The item — which measures about 4.3 by 2.3 inches (10.9 by 5.8 centimeters) — represents the oldest known elephant bone tool ever found in Europe, according to the study, which was published Wednesday (Jan. 21) in the journal Science Advances, and demonstrates human relatives' high level of resourcefulness and ability to adapt to new environments as they settled in northern climates.

While evidence suggests that early human relatives used elephant bones and tusks throughout the Paleolithic period for a wide range of purposes, it's "very rare" to find an elephant-bone tool of this age or older anywhere in the world, said study co-author Silvia Bello, a paleoanthropologist at the Natural History Museum in London.

The "unexpected" find of one of the world's oldest elephant bone tools indicates a relatively advanced level of technological development, thus highlighting the innovation, resourcefulness and craftsmanship of archaic human relatives almost half a million years ago, the researchers said in the study.

While the researchers are unsure which group of human relatives used the elephant tool, given the age of the tool and the location where it was found, two candidates are early Neanderthals or Homo heidelbergensis, Bello told Live Science in an email.

The tool "provides an extraordinary glimpse into the ingenuity of the early human ancestors who made it," Bello said.

The fossilized bone artifact was originally uncovered in the early 1990s during excavations at the archaeological site of Boxgrove in southern England. This internationally renowned site has yielded many finds that have shed light on Paleolithic life around half a million years ago. These include various bone and stone tools, numerous animal remains displaying signs of butchery, and even the oldest human remains ever found in Britain.

The significance of the bone artifact was not immediately apparent. But a recent analysis of the artifact conducted by Bello and her co-author Simon Parfitt, an archaeologist at the Institute of Archaeology at University College London, revealed that the artifact represents an elephant bone fragment deliberately shaped into a "retoucher" tool.

Retouchers were used to shape and resharpen the edges of hand axes. The elephant bone retoucher would have contributed to the production of the "finely worked" hand axes that were thought to have been used primarily as cutting tools and are typical of Boxgrove, according to the study.

"The elephant bone tool shows signs of being shaped and used to knap and re-sharpen lithic tools while the bone was still fresh, suggesting that these humans knew that elephant bone was a great material for this," Bello said.

The find represents the only documented case of elephant bone being used to make a retoucher, according to the researchers. Knapping tools made from organic materials such as bone, antler and wood were essential pieces of equipment for early humans but are rarely preserved in the archaeological record.

Furthermore, prehistoric elephant bone remains are "exceptionally rare" at Boxgrove, suggesting that archaic humans in the area came across this resource infrequently, the study authors noted. Nonetheless, it appears that the creators of the tool recognized the usefulness of the material.

"This remarkable discovery showcases the resourcefulness of our ancient relatives," Parfitt told Live Science in an email. "They possessed not only a deep knowledge of the local materials around them, but also a sophisticated understanding of how to craft highly refined stone tools."

"Elephant bone would have been a rare but highly useful resource, and it's likely this was a tool of considerable value," he said in a statement.

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