Hundreds of suckers on an octopus’ tentacles can stick to most surfaces but not to its own skin.
Scientists studying the cephalopod now believe it emits a specific chemical signal from its skin which prevents it from sticking to itself. Without this, scientists believe, the long tentacles could well become entangled or attached to another octopus.
Research continues to be able to identify the active element of the signal.
The discovery could help researchers designing bio-inspired ''soft'' robots with tentacle-like manipulators.
Animals with rigid skeletons always know exactly where their ‘arms’ are, but this is not the case for the octopus. Experiments indicate that the cephalopod’s tentacles have a high degree of freedom.
Other tests probed whether an octopus would grab hold of live or dead octopus skin or extract, which they did not.
The researchers wrote in the journal Current Biology: ''The results so far show, and for the first time, that the skin of the octopus prevents octopus arms from attaching to each other or to themselves in a reflexive manner.
The findings are being shared with other scientists working on the European Stiff-Flop project which aims to develop a flexible manipulator shaped like an octopus tentacle which could be used for surgery.
Soft robots can reshape their size and manoeuvre around obstacles, such as those found inside the body.
