Octopuses running like humans?

UC Berkeley researchers discover species that can make an escape--remaining camouflaged--on two of their eight arms.

Michael Kanellos Staff Writer, CNET News.com
Michael Kanellos is editor at large at CNET News.com, where he covers hardware, research and development, start-ups and the tech industry overseas.
Michael Kanellos
Researchers at the University of California, Berkeley, have determined that two species of octopuses can run away from danger.

octopus Apparently in an attempt to evade predators, the coconut octopus of Indonesia, or octopus marginatus, and the Australian octopus aculeatus can scuttle across the sea floor on two legs, according to graduate student Crissy Huffard and professor Robert Full.

Huffard first saw a coconut octopus running on two legs during a field trip in 2000 but only recently was able to capture the phenomenon on film. A paper on the subject was published last week in the journal Science.

When walking, these octopuses use their back arms like tank treads: A line of suckers is planted on the ground, and the octopus pulls itself forward.

Huffard clocked one coconut octopus traveling at approximately 2.5 feet per second and another moving at 5.5 feet per second going backward. That is slower than the animals can get through the water but faster than they can crawl.

Running, though, enables the octopuses to get away from a predator while remaining camouflaged, or at least not look like a typical fleeing octopus, according to Huffard and Full, who is a professor of integrative biology at UC Berkeley.

"This bipedal behavior allows them to get away and remain cryptic," Huffard said in a prepared statement. "This is the first underwater bipedal locomotion I know of."