Octopuses are some of the most intelligent and flexible invertebrates on Earth. With eight highly adaptable arms, these marine animals can hunt prey, communicate, build shelters, and even defend themselves—all while thriving in diverse underwater habitats.
New Study Explores Octopus Arm Movements in Natural Habitats
A groundbreaking study by Florida Atlantic University’s Charles E. Schmidt College of Science, in collaboration with the Marine Biological Laboratory (MBL) in Woods Hole, Massachusetts, has revealed how wild octopuses use their arms with precision and versatility. Published in Scientific Reports, this is the first research to connect octopus arm movements to whole-body behaviors in complex, real-world environments.
Researchers observed three octopus species across six shallow-water habitats—five in the Caribbean and one in Spain. By analyzing nearly 4,000 arm movements from 25 underwater videos, they identified 12 unique arm actions tied to 15 different behaviors.
Front and Back Arms Play Different Roles
The study discovered that while every arm can perform any type of movement, there’s a clear division of labor. Front arms are mainly used for exploration—feeling around rocks or probing crevices—while back arms are more involved in propulsion and movement.
Four Types of Arm Deformation Observed
The team documented almost 7,000 arm deformations, including:
- Bending – Curving the arm, mostly near the tips.
- Elongating – Extending the arm, usually closer to the body.
- Shortening – Contracting the arm to pull objects or reposition.
- Torsion (Twisting) – Rotating for grip or manipulation.
These specialized movements highlight the complex motor control octopuses possess. Sometimes, a single arm worked independently—like grabbing prey—while in other instances, multiple arms coordinated for actions like crawling or ambush hunting, also known as “parachute attacks.”
Adaptations for Survival and Camouflage
Lead author Chelsea O. Bennice, Ph.D., explained that octopuses rely on these abilities not just for foraging but also for survival tactics. For example, when crossing open areas, they may use several arms to mimic floating seaweed or moving rocks to stay hidden from predators. Their flexible arms are also critical for:
- Building protective dens.
- Competing with rival males during mating.
- Fending off predators.
Importance for Neuroscience and Robotics
Co-author Roger Hanlon, Ph.D., emphasized that studying octopuses in their natural habitats provides vital insights into their sensory world. These findings could inspire advances in soft robotics, neuroscience, and animal behavior research, as octopus arms are a living model of dexterity and adaptability.
Diverse Habitats Studied
The research covered a variety of environments, from smooth sandy seabeds to complex coral reefs, showing how octopuses adjust their movements depending on habitat. This adaptability is a key reason why octopuses thrive in such a wide range of ecosystems.
Why This Matters
Understanding how octopuses coordinate their arms deepens our knowledge of marine biology and could influence future technology. As Bennice noted, “These versatile abilities allow octopuses to thrive in a wide range of habitats, and studying them opens exciting opportunities for innovation in multiple scientific fields.”
Reference:
Florida Atlantic University and Marine Biological Laboratory. Octopus arm flexibility facilitates complex behaviors in diverse natural environments. Scientific Reports (2025). DOI: 10.1038/s41598-025-10674-y