London - The oldest stone tools ever discovered, dating back 3.3 million years, have been unearthed in Kenya.
The tools, which were created about 700 000 years before the previous most ancient stone implements, have been hailed as a “new beginning to the known archaeological record”.
More than 100 primitive hammers, anvils and other stone artefacts have been unearthed in the desert hills bordering the western shores of Lake Turkana in the Kenyan Rift Valley.
The discovery undermines the argument that making stone tools was a defining characteristic of the direct human lineage leading to the emergence of Homo sapiens, because it required a unique combination of manual dexterity and cognitive ability.
The stone tools predate the earliest known members of the Homo genus by about half a million years, suggesting that the implements were made by another species of “hominin” - the non-ape human tribe - which may or may not have been one of our direct ancestors, scientists said.
Scientists do not yet know which species made the stone tools but they suggest that a possible candidate is a “flat-faced”, ape-like hominin called Kenyanthropus platyops which was known to have lived in the same place at the same time. But they accept that the toolmaker could also have been another, as-yet undiscovered hominin species.
“This is a momentous and well-researched discovery. I have seen some of these artefacts in the flesh, and I am convinced they were fashioned deliberately,” said Professor Bernard Wood, of the George Washington University in Washington DC, an expert on early human origins who was not involved in the discovery.
The origin of stone tool-making is seen as crucial to the understanding of human prehistory because ultimately it led to greater social cooperation in hunting and the later evolution of more sophisticated tools and weapons made of flint, wood and animal bone.
Archaeologists discovered the stone artefacts in a previously unexplored area at a known fossil site on the shores of Lake Turkana, which they discovered by accident after taking a wrong turn one morning in July 2011.
“[They] shed light on an unexpected and previously unknown period of hominin behaviour and can tell us a lot about cognitive development in our ancestors that we can't understand from fossils alone,” said Sonia Harmand, of Stony Brook University in New York, and lead author of the study published in the journal Nature.
Richard Potts, director of human origins at the Smithsonian National Museum of Natural History, said: “Researchers have thought there must be some way of flaking stone that preceded the simplest tools known until now.
“Harmand's team shows us just what this even simpler altering of rocks looked like before technology became a fundamental part of early human behaviour.”
The Independent