A trove of sophisticated stone tools recently dug up from a South African cliff suggests that early modern humans had developed complex cognitive ability anywhere from 6,000 to 10,000 years earlier than many believe.
In a study published in the journal Nature, researchers said they had unearthed a large number of small stone blades going back some 71,000 years. The heat-treated blades appear to have been designed for tipping spears or arrows that could be used for hunting game. Crucially, the discovery indicates that these ancestors had the cognitive ability to manipulate complex tools. In addition, they were able to pass on their inventions to future generations. And that, in turn, suggests the use of sophisticated language.
"What it's showing us is that these people were like you and I," said Curtis Marean, a paleoanthropologist at Arizona State University in Tempe, Ariz., co-author of the study, and leader of the South Africa project. "They were smart people."
The latest discovery sheds light on several burning questions in evolution: When did humans get their modern cultural smarts? Was it early or late in their history? Did advanced cognition emerge gradually or suddenly?