10,000 generations of hominins used the same stone tools to weather a changing world

“This site reveals an extraordinary story of cultural continuity,” Braun said in a recent press release.

When the going gets tough, the tough make tools

The Nomorotukunan stone tool layers span the transition from the Pliocene to the Pleistocene, during which Earth’s climate became progressively cooler and drier after a warm period of 2 to 3 million years. Pollen and other microscopic traces of plants in the Nomorotukunan sediments bear witness to this: the marsh at the edge of the lake gradually dried up, giving way to arid grasslands dotted with shrubs. On a shorter time scale, Nomorotukunan hominids faced forest fires (because of microcharcoal in the sediments), droughts, and rivers that dried up or changed course.

“As vegetation changed, tool making remained stable,” said Rahab N. Kinyanjui, an archaeologist at the National University of Kenya, in a recent press release. “That’s resilience.”

The making of sharp stone tools may have helped generations of hominids survive in a changing and drying world. In the hot, humid Pliocene, finding food would have been relatively easy, but as conditions became more difficult, hominids likely had to scavenge or dig for food. At least one animal bone at Nomorotukunan bears cut marks where long-ago hominids carved up the carcass for meat – something our lineage isn’t really equipped to do with bare hands and teeth. Tools would also have allowed early hominids to dig up and cut tubers or roots.

It’s fair to assume that sharpened wooden sticks probably also played a role in this particular work, but wood doesn’t tend to last as long as stone in the archaeological record, so we can’t be sure. What East Some are the stone tools and cut bones, which allude to what Utrecht University archaeologist Dan Rolier, co-author of the paper, calls “one of our oldest habits: using technology to protect us from change.”

A story as old as time

Nomorotukunan may be hinting that Oldowan technology is even older than the earliest tools archaeologists have discovered so far. The oldest tools discovered in the deepest layer of Nomorotukunan are the work of experienced flint knappers who knew where to strike a stone and at exactly what angle to give it the desired shape. They also clearly knew how to select the right stones for the job (fine-grained chalcedony for the win, in this case). In other words, these tools were not the work of a group of hominids who were simply trying, for the first time, to put stones together.