Overview
- The peer‑reviewed study, which was published Nov. 5, 2026 in the Journal of Experimental Biology, documents reproducible three‑step and four‑step sequences octopuses use to pass through openings.
- Researchers measured eye‑to‑eye distance as a practical proxy for a stiff cranial cartilage sheath and built clear acrylic boxes with holes sized slightly larger or about 5 mm smaller than that measurement to test passage strategies.
- Common octopuses (Octopus vulgaris) used a three‑step method for wider holes and added a fourth step—threading all arms first, then compressing the mantle—to get through tighter gaps, while Mayan octopuses (Octopus maya) usually avoided the narrower openings.
- The experiments used small samples of subadult or juvenile animals (three O. vulgaris and four O. maya) in lab trials, so authors and coverage note limits on generalizing to all ages, species, or wild conditions.
- Authors propose the identified motor primitives and shape‑change tactics could guide new soft, octopus‑inspired robots for search‑and‑rescue and exploration by allowing bodies to reconfigure rather than rely on slender, snake‑like designs.