For a century, macaques used simple stone tools to smash open shellfish. It took them just 13 years to learn to use stones to crack open oil palm nuts introduced by humans. They may be the first non-human primates to have begun adapting their Stone Age technology to exploit a new ecological niche.

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For a century, macaques used simple stone tools to smash open shellfish. It took them just 13 years to learn to use stones to crack open oil palm nuts introduced by humans. They may be the first non-human primates to have begun adapting their Stone Age technology to exploit a new ecological niche.