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Smart Arms

Imagine if your arms and legs had minds of their own. Your brain might tell your hand to pick up a pencil, but your arm might surprise you by deciding to lift it with just one finger! Israeli researchers have found that an octopus's eight arms work in much this way.

The octopus has a brain in its head, but it also has a complex nervous system (the body's chief control system) in each of its eight arms. This allows each arm to act on its own — independent of the brain.

Scientists have long considered the octopus to be among the smartest of all invertebrate (without a backbone) animals. Now they know that the octopus brain determines only the direction and the speed at which an arm moves. The rest is up to the arm. The octopus is the first known animal with this quality. But scientists suspect that squids and cuttlefish — the octopus's closest cousins — might share this trait.

The Israeli scientists had been studying octopus's arms for years. They want to develop smarter robots and hope to apply what they learn to robotic arms. Flexible and smart robotic arms, similar to those of the octopus, could be useful in delicate surgeries.
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