How Octopuses Squeeze Through Tiny Openings

How does an octopus get through a tiny hole?

It changes its shape and feeds its arms and body through the opening in stages. In laboratory observations, researchers saw a consistent sequence of movements, with three or four moves depending on the opening’s size ¹.

The key is that an octopus is mostly soft muscle. Its arms and much of its body can bend and deform, unlike a body built around a rigid skeleton ¹³. But it is not entirely without firm parts, so squeezing has limits.

What happens during the squeeze?

The study describes a step-by-step escape rather than the animal passing through all at once. The reported number of moves varied with hole size, so there is not one fixed sequence that applies to every opening ¹.

In broad terms, the octopus must direct its flexible arms through the gap and then bring the rest of its body after them. The available source summaries do not spell out each movement in enough detail to describe a precise, universal choreography. The main finding is that the animals used repeatable sequences in the researchers’ tests ¹.

How small can an opening be for an octopus?

There is no single size limit given in the available source material. The answer depends at least in part on the animal and the opening. Researchers tested holes that were slightly wider or narrower than the distance between each octopus’s eyes ².

That eye-to-eye distance served as an estimate of the width of the cartilage case around the central nervous system. Earlier assumptions treated this firm structure as a guide to the smallest gap an octopus could pass through, but the supplied reports do not establish a universal minimum opening size ².

Which octopuses were studied?

Researchers tested Mayan octopuses, also known as Octopus maya, and young common octopuses, Octopus vulgaris ². They placed the animals in clear plastic aquarium boxes connected by holes of different sizes ².

The findings describe these animals in laboratory tests. They do not, by themselves, establish that all octopus species or individuals behave in exactly the same way.

Why does this research matter?

Octopuses’ ability to change shape is familiar, but researchers have not often studied systematically how they pass through very small openings ¹. Tracking the movements gives scientists a clearer account of how this kind of escape works.

The work could also inform soft robotics: machines made with flexible materials rather than only rigid parts ¹. That is a possible application, not evidence that the study has already produced a robot with an octopus’s abilities.