Making decisions, one leg at a time
Footage shows octopus tentacles making independent decisions. Andrew Masterson reports.
The graph appearing over this footage of an octopus exploring a tank represents the different angular speed of each of the tentacles – a phenomenon of great interest to scientists researching models for extra-terrestrial life.
Recent research has shown that octopus tentacles can initiate independent action in response to environmental stimuli. In other words, they don’t rely solely on signals sent by the brain; they also can receive instructions from the peripheral nervous system.
This represents a bottom-up, in contrast to the vastly more common top-down, model of intelligence, making the octopus arguably the closest thing to an alien lifeform living on Earth.
“It's an alternative model for intelligence,” says Dominic Sivitilli from the University of Washington in the US. “It gives us an understanding as to the diversity of cognition in the world, and perhaps the universe.”
Stivilli and colleagues modelled the synchronous and asynchronous movements of octopus tentacles and presented their results at the AbSciCon 2019 astrobiology conference held in Bellevue, Washington, US.
“The octopus' arms have a neural ring that bypasses the brain, and so the arms can send information to each other without the brain being aware of it" Sivitilli explains.
“So while the brain isn't quite sure where the arms are in space, the arms know where each other are and this allows the arms to coordinate during actions like crawling locomotion.”