Scientists Solve Nagging Octopus Question

If you had eight arms, how would you avoid tripping and tangling yourself up—especially if the arms were covered in suckers? Somehow, octopuses manage, but scientists didn't know how. New research indicates, however, that the suckers on the arms are able to identify other arms and avoid sticking to them, National Geographic reports. "Two-thirds of (an octopus') nerves are not in its brain, but in its arms," a researcher says. In other words, as NPR puts it, "It's kind of like the eight arms have minds of their own."

And they continue to function for about an hour even after being severed from an octopus' body, as can happen in the wild. Researchers found that amputated arms didn't stick to themselves or other arms—unless the other arms' skin was removed. In a petri dish half-covered in octopus skin, amputated arms attached only to the part of the dish without the skin covering. The arms have sensors that allow them to "taste" what they touch, and this taste appears to tell them not to stick to other arms, says a researcher. "This is a sensory capability previously unknown in octopus or any other cephalopod," an expert tells NPR. (In other sea creature news, researchers recently named a stunning—and mysterious—new species of jellyfish.)