Hominins carried rocks for tools 2.6m years ago

More than 2.6 million years ago in what is now south-western Kenya, ancient humans were carrying stone over long distances to fashion tools that allowed them to butcher large animals such as hippopotamuses.

Science AdvancesNew research, led by scientists at the Smithsonian’s National Museum of Natural History and the Cleveland Museum of Natural History, has pushed back the earliest known evidence of resource transport by some 600,000 years. The findings were published this week in Science Advances.

The tools, known as the Oldowan toolkit, were discovered at Nyayanga on the Homa Peninsula, a fossil-rich region on the eastern shores of Lake Victoria. Excavations revealed hundreds of stone flakes and cores alongside butchered hippo bones, suggesting the site was used repeatedly by early hominins.

Analysis showed that many of the tools had been made from volcanic and metamorphic rocks such as rhyolite and quartzite, which are absent locally but found more than six miles away. Researchers say this shows early humans were capable of planning ahead and mentally mapping their surroundings to acquire suitable raw material.

“The knowledge and intent to bring stone material to rich food sources was apparently an integral part of toolmaking behaviour at the outset of the Oldowan,” said Rick Potts, senior author of the study.

The Oldowan toolkit, which included hammerstones and sharp-edged flakes, allowed early humans to slice, scrape and pound food and wood, greatly expanding their adaptability. Its use at Nyayanga represents the oldest known example of hominins butchering large prey.

The identity of the toolmakers remains uncertain. Teeth from the genus Paranthropus were found in the same deposits, raising the possibility that more than one branch of the human family tree used such tools.

“It suggests there was a greater diversity of hominins making early stone tools than previously thought,” said lead author Emma Finestone of the Cleveland Museum of Natural History.