The world's oldest stone tools have been discovered, scientists report. They were unearthed from the shores of Lake Turkana in Kenya, and date to 3.3 million years ago.
They are 700,000 years older than any tools found before, even pre-dating the earliest humans in the Homo genus.
The find, reported in Nature, suggests that more ancient species, such as Australopithecus afarensis or Kenyanthropus platyops, may have been more sophisticated than was thought.
"They are significantly earlier than anything that has been found previously," said Dr Nick Taylor, from the National Centre of Scientific Research (CNRS) in France and the University of Leiden in the Netherlands.
"It's really quite astonishing to think what separates the previous oldest site and this site is 700,000 years of time. It's monumental."