Using argon-argon dating—a technique that compares different isotopes of the element argon—researchers determined that the volcanic ash layers entombing the tools at Gademotta date back at least 276,000 years.
Many of the tools found are small blades, made using a technique that is thought to require complex cognitive abilities and nimble fingers, according to study co-author and Berkeley Geochronology Center director Paul Renne.
Some archaeologists believe that these tools and similar ones found elsewhere are associated with the emergence of the modern human species, Homo sapien.
“It seems that we were technologically more advanced at an earlier time that we had previously thought,” said study co-author Leah Morgan, from the University of California, Berkeley.
Humans 80,000 Years Older Than Previously Thought?