In July 2011 a team of archaeologists discovered a set of stone tools that are 3.3 million years old, made by our hominin ancestors.
The discovery meant that scientists had to revise their previous opinion that the first tools were made 2.6 million years ago, and may even extend tool-making to beyond the Homo genus. It was thought that the genus gained an edge over its rival because of the use of stone tools, but that theory has now been thrown into doubt.
Oldest stone tools made before Homo genus arrived
Scientists actually discovered the tools after taking a wrong turn near the western shore of Lake Turkana, and immediately knew that they were onto something important. Co-leaders of the project, Sonia Harmand, a research associate professor at Stony Brook University in New York, and Jason E. Lewis, found evidence that some ancient hominins were intentionally breaking stones in order to make tools.
The team carried out field research and lab analysis before publishing their findings in the journal Nature. Neither the uses of the stone tools or the identity of their makers is known.
Dr. Harmand and Dr. Lewis believe that the tools were produced by a member of the human family that lived before the genus Homo existed. The previous record for the oldest evidence of toolmaking was held by a site in Ethiopia.
Ongoing investigations into early toolmaking
It is not yet known quite how early toolmaking began, although some scientists believe that it could have started around 7 million years ago.
The only known hominin which existed as long ago as the tools have been dated was Australopithecus, found throughout East Africa. The makers could also have been Kenyanthropus platyops, but scientists are still unsure whether they are a separate hominin entity.
Questions remain as to whether the rocks are really tools, and what the hominins were doing with such large and heavy implements. The tools which previously held the record as the oldest in the world were far smaller and simpler, and scientists will continue to search for older tools.
Dr. Harmand and Dr. Lewis will make another trip to Lake Turkana this summer in order to continue their investigation.