World's oldest stone tools are older than modern humans
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Scientists working at the site of Dikika, Ethiopia in 2010 where fossils belonging to Lucy's species had previously turned up said they had recovered 3.4 million year-old animal bones bearing distinctive marks. They argued hominins had made the marks in the course of slicing meat off the bones with stone tools. The claim caused heated debate with some scientists saying the alleged cut marks were instead the result of the bones having been trampled by passing animals. Others suggested they were bite marks from crocodiles.