Octopus Arms Coordinate Movement, Sensing and Body Illusions in New Studies | DongA Science

The octopus’s eight arms are in constant motion. They probe the seafloor as it moves, snatch prey in an instant, and freely explore narrow crevices. But does an octopus use all eight arms in exactly the same way? To us, they appear to flail about freely, yet hidden within that motion are unexpected functions. As scientists closely examine how octopuses move and sense the world, intriguing facts about their eight arms are being revealed one by one.

Octopuses move their eight arms freely to search for food and avoid danger. In Korean they are commonly called “octopus legs,” but given their ability to grasp and manipulate a wide variety of objects, anatomically they are closer to “arms.” So how does an octopus use its eight arms depending on the situation?

A research team led by Chelsea Bennice at the Harbor Branch Oceanographic Institute of Florida Atlantic University in the United States, together with scientists from the Marine Biological Laboratory in Woods Hole, analyzed the arm movements of wild octopuses and published their findings on September 11, 2025, in the international journal Scientific Reports.