Octopuses escape tanks and containers by executing precise, multi-step physical strategies depending on the size of the opening. Published November 5 in the Journal of Experimental Biology, new research shows that common octopuses use a three-step or four-step maneuver to squeeze their squishy bodies through tiny holes.
Octopuses have earned a legendary reputation for pulling off great escapes. Famous instances include Inky fleeing from New Zealand’s national aquarium, while other cephalopods routinely Houdini their way out of tanks and off boats by squeezing through narrow slits and tight spaces, sciencenews.org reported.
Now, researchers know exactly how common octopuses pull it off. These masterful getaways involve a consistent, step-by-step game plan, researchers reported November 5 in the Journal of Experimental Biology. Because octopuses are mostly squishy muscle, they can shape-shift despite having a few rigid body parts.
“It’s one of the most characteristic behaviors of octopuses in popular awareness, but the strategies octopuses use have not really been examined systematically,” said Robyn Crook, an evolutionary biologist at San Francisco State University who was not involved in the research, as reported by sciencenews.org.
Observing Escape Artists in Acrylic Boxes
Sneaking through small spaces is far from just a party trick for these marine animals. Michael Kuba, a biologist at the University of Naples Federico II in Italy, explained that octopuses use the skill to find hidden food and avoid becoming food themselves, according to sciencenews.org.
Three common octopuses (Octopus vulgaris) and four Mayan octopuses (Octopus maya) were watched by Kuba and his colleagues as they approached small openings. To gauge the dimensions of the hard cartilage protecting their brains, the team calculated the span between each subject’s eyes.
Researchers then designed acrylic boxes featuring holes slightly smaller or larger than that eye-to-eye measurement. They placed the octopuses inside to observe the mechanics of their escape.
Two Distinct Strategies for Different Apertures
Common octopuses deployed one of two physical escape strategies depending on the exact size of the hole. When the opening was wider than the distance between their eyes, the animals pushed themselves through in three quick steps, sciencenews.org reported.
First, they snuck one or two arms through the hole before threading a couple more arms through. Finally, they used those already-snaked arms to push against the box, yanking their head and the rest of their arms through in one rapid motion. The entire operation took only a few seconds.
When faced with a narrower hole, common octopuses added a fourth step to the sequence. They shoved all of their arms through the opening first before squishing their head and bulbous mantle through.
Behavioral Differences Among Species
Mayan octopuses behaved much more cautiously during the experiments than their common octopus counterparts. When confronted with a narrower hole, Mayan octopuses did not attempt to fit inside and usually ignored the opening entirely.
Kuba noted that this difference likely stems from biology or environmental adaptation. Mayan octopuses live in sandy, rocky areas where they may disappear under rocks, meaning they rarely need to cram themselves through tiny holes.
How Octopuses Deform Bodies and Escape Through Sequential Movements
- Squishy Muscle: The absence of a rigid skeletal frame allows octopuses to deform their bodies to fit dimensions smaller than their brain cartilage.
- Systematic Steps: Escaping requires specific sequential movements, deploying arms first for leverage before pulling the mantle through.
- Behavioral Variance: Different species show distinct caution levels based on their natural habitats and survival needs.
Inspiring New Soft Robotics Designs
Researchers hope these biological escape artists will inspire a new generation of soft robots capable of morphing their shape. Wenci Xin, a robotics researcher at the National University of Singapore, noted that this capability could help machines overcome environmental limitations and enter hard-to-reach spaces.
Current robots built to fit through tiny holes tend to rely on rigid, snake-shaped configurations. Researching how eight-armed contortionists move through different types of openings—such as slits or tubes rather than circular holes—could unlock entirely new robotic designs.
References
- Journal of Experimental Biology (2026): Research on octopus escape strategies and behavioral mechanics.
