From BBC News:
Two species of octopus have been observed moving in an upright bipedal stride since the discovery was announced in March this year. And scientists at the University of California at Berkeley believe they can develop artificial muscles for use in a new field of soft robotics using the studies of the octopus’s movement. “Each arm rolls along the suckers and pushes the animal back, and then the other arm touches down, rolls along the suckers, and pushes the animal back again,” biologist Chrissy Hufford explained to BBC World Service’s Science In Action programme.
“That’s why it was such a surprise to see – because every other example of bipedal locomotion before had involved the support of a rigid skeleton,” Dr Hufford added. “As we know, octopi and other cephalopods don’t have anything rigid in their arms – they are supported by bands of muscle… that allows them flexibility, but also some support.” This extreme flexibility and strength is of great interest to biologist Bob Full, who believes the octopus is an excellent model for how robots that move might be built without hard parts.