Nut-cracking monkeys don't just use tools. They use tools with skill.
That's the conclusion of a new study that finds similar tool-use strategies between humans and Brazil's bearded capuchin monkeys, which use rocks to smash nuts for snacks. Both monkeys and humans given the nut-smashing task take the time to place the nuts in their most stable position on a stone "anvil," the study found, keeping the tasty morsels from rolling away.
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