A Walking Two-Legged Octopus? ======================
Two species of tropical octopus have evolved a neat trick to avoid predators - they lift up six of their arms and walk backward on the other two. When walking, these octopuses use the outer halves of their two back arms like tank treads, alternately laying down a sucker edge and rolling it along the ground.
Robert Full, professor of integrative biology at UC Berkeley, and grad student Crissy Huffard, co-authors of a report in the March issue of Science, think that this bipedal walking is a strategy octopuses use to backpedal away from predators while remaining camouflaged. "This is the first underwater bipedal locomotion I know of, and the first example of hydrostatic bipedal movement," says Huffard.
And what does science think it can learn from this? According to Full, "understanding behavior like this could usher in a new frontier of 'soft' robotics," in contrast to the rigid robots common today.