JERUSALEM (NBC/RTV) — Scientists in Israel say they’ve solved a mystery concerning one of the sea’s most intriguing creatures.
They wanted to understand why an octopus’ arms never become entangled, even though the motor control systems for all eight limbs act independently of each other.
The research team from the Hebrew University of Jerusalem says that a chemical produced by octopus skin prevents their suckers sticking to their own limbs.
“An isolated octopus arm is amazing. It continues to live and behave for more than an hour after amputation,” said neurologist Guy Levy. “So we took arms like this, and we saw that the arm would grab anything but another amputated arm, another part, regardless of its origin — whether it was own arm or an arm from another octopus of the same species.”
From this finding, Levy and fellow neuroscientist Nir Nesher worked to find out how the octopuses avoid tying themselves up in knots.
They suspected the aversion of the arms to each other had something to do with their skin.
They found that the chemoreceptors on the rim of each arm’s suckers sense chemicals in the skin, and that inhibits their grabbing reflex.
And they will avoid their own limbs but not other limbs.
Levy says a self-recognition system could contribute to the development of bioinspired robots.