Monkeys are using tools really intelligently.
New research discovers that wild bearded capuchins have been using stone tools for 3000 years. For example, they smack an appropriately shaped stone down on nuts and shellfish placed on another stone being used as an anvil. Aspects of this behaviour have become more sophisticated over the period. On the other hand, the monkeys are not smart enough to keep their stone tools after using them. This means they have to hunt out new tools each time.
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