The mystery of how an octopus manages to avoid getting tangled by its own suckers is finally solved.

Binyamin Hochner and his colleagues had been working with octopuses for many years, focusing especially on their flexible arms and body motor control. There is a very good reason that octopuses don't know where their arms are exactly, in the same way that people or other animals do.
"Our motor control system is based on a rather fixed representation of the motor and sensory systems in the brain in a formant of maps that have body part coordinates," Hochner explains.
That works for us because our rigid skeletons limit the number of possibilities. "It is hard to envisage similar mechanisms to function in the octopus brain because its very long and flexible arms have an infinite number of degrees of freedom," Hochner continues. "Therefore, using such maps would have been tremendously difficult for the octopus, and maybe even impossible."
To answer that question, the researchers observed the behavior of amputated octopus arms, which remain very active for an hour after separation. Those observations showed that the arms never grabbed octopus skin, though they would grab a skinned octopus arm. The octopus arms didn't grab Petri dishes covered with octopus skin, either, and they attached to dishes covered with octopus skin extract with much less force than they otherwise would.
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In contrast to the behavior of the amputated arms, live octopuses can override that automatic mechanism when it is convenient. Living octopuses will sometimes grab an amputated arm, and they appear to be more likely to do so when that arm was not formerly their own.
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"Soft robots have advantages [in] that they can reshape their body," Nesher says. "This is especially advantageous in unfamiliar environments with many obstacles that can be bypassed only by flexible manipulators, such as the internal human body environment."
In fact, the researchers are sharing their findings with European Commission project STIFF-FLOP, aimed to develop a flexible surgical manipulator in the shape of an octopus arm. "We hope and believe that this mechanism will find expression in such new classes of robots and their control systems," Hochner says.
Source-Eurekalert