Octopus arms are among the most flexible and versatile structures in the natural world. Their unique agility has inspired robotics researchers to explore new designs for soft, flexible robots that could navigate tight spaces, perform delicate tasks, or even deliver vital supplies during rescue missions in disaster zones.
A groundbreaking study by scientists from the Marine Biological Laboratory (MBL) in Woods Hole and Florida Atlantic University (FAU) has now produced the most detailed behavioral catalog of octopus arm movements ever recorded. Published in Scientific Reports (2025), this research sheds new light on how octopuses use their eight arms for foraging, locomotion, and interaction with their environment.
📹 Studying Octopuses in Their Natural Habitat
Researchers video-recorded 25 wild octopuses across six locations in the Atlantic Ocean, Caribbean Sea, and Spain. This field-based approach allowed them to observe behaviors that could never be fully replicated in laboratory settings.
“Recording octopuses in their natural environment gave us a deeper understanding of their complex behaviors,” explained Chelsea Bennice, FAU research fellow and first author of the study.
Senior scientist Roger Hanlon of MBL, who has studied cephalopods for over 25 years, emphasized that this is the first full ethogram—a detailed catalog—of wild octopus arm movements. Earlier studies were mostly conducted in laboratory tanks, limiting the range of behaviors observed.
🌊 Sensory Superpowers and Camouflage
Octopuses rely heavily on tactile sensing through their suckers rather than on vision. Each arm contains about 100 highly sensitive suckers, which Hanlon describes as “chemo-tactile geniuses”—combining the functions of the human nose, lips, and tongue in one structure.
Their camouflage abilities—rapidly changing skin color and texture—made them challenging to locate in the wild. Divers searched for clues like leftover shells and food debris to find octopus dens. Octopuses typically spend 80% of their time hidden in dens, emerging once or twice daily to forage.
🔬 Breaking Down the Movements
The researchers analyzed field footage frame-by-frame, dividing each arm into three segments to document 12 distinct types of movements. Key discoveries include:
- Elongation and shortening occur mostly near the base of the arm.
- Bending and fine probing are more common at the tips.
- Arms are used for walking on the seafloor, swimming, probing crevices for prey, and manipulating objects.
“These actions form the foundation of all octopus behaviors,” said Kendra Buresch, MBL co-author.
🤖 Inspiring Next-Generation Robotics
This research has significant implications beyond marine biology. Robotics engineers are eager to replicate octopus-like movement for search-and-rescue missions or medical devices that can navigate narrow passages inside the human body.
Hanlon highlights the potential:
“To deliver tools or supplies into tight spaces—whether under rubble or underwater—you need a flexible, precise appendage like an octopus arm.”
📑 Study Reference
Source: Marine Biological Laboratory and Florida Atlantic University
Published in: Scientific Reports (2025)
DOI: 10.1038/s41598-025-10674-y