{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,6]],"date-time":"2026-11-06T09:37:22Z","timestamp":1793957842383,"version":"4.8.0"},"reference-count":35,"publisher":"The Company of Biologists","issue":"21","license":[{"start":{"date-parts":[[2026,11,1]],"date-time":"2026-11-01T00:00:00Z","timestamp":1793491200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/www.biologists.com\/user-licence-1-2\/"}],"funder":[{"name":"National University of Singapore","award":["A-0009125-02-00"],"award-info":[{"award-number":["A-0009125-02-00"]}],"id":[{"id":"https:\/\/ror.org\/01tgyzw49","id-type":"ROR","asserted-by":"crossref"}]},{"name":"National University of Singapore","award":["A-8003743-00-00"],"award-info":[{"award-number":["A-8003743-00-00"]}],"id":[{"id":"https:\/\/ror.org\/01tgyzw49","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,11,1]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>With sophisticated behaviors, a flexible body and unique motor control, octopuses are compelling models for both biological and bio-inspired robotics. Their lack of a rigid skeleton allows them to undergo extreme deformations, letting them navigate tight apertures and narrow geometries, offering a biological solution to one of the most persistent challenges in robotics. However, how the animal organizes its arms and body to interact and adapt to environmental constraints remains unclear. Here, we examined octopus behavior when squeezing through small apertures to identify the underlying transition strategies. We characterized a consistent \u20183-step\u2019 or \u20184-step\u2019 strategy with progression: probing, shifting 3\u20135 arms and squeezing. Strategy selection is governed by aperture size, and in smaller openings, non-shifted arms and mantle are squeezed separately, adding an additional step. These findings provide insights into mechanisms of octopus squeezing behavior and offer a robust biological blueprint for the design of next-generation bio-inspired soft robots.<\/jats:p>","DOI":"10.1242\/jeb.252825","type":"journal-article","created":{"date-parts":[[2026,11,5]],"date-time":"2026-11-05T21:01:53Z","timestamp":1793912513000},"source":"Crossref","is-referenced-by-count":2,"title":["Overcoming environmental constraints: octopus uses 3-step or 4-step strategies to squeeze through small holes"],"prefix":"10.1242","volume":"229","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2582-8037","authenticated-orcid":false,"given":"Wenci","family":"Xin","sequence":"first","affiliation":[{"name":"College of Design and Engineering, National University of Singapore 1 Department of Mechanical Engineering , , Singapore 117575 ,","place":["Singapore"]},{"name":"Advanced Robotics Centre, National University of Singapore 2 , Singapore 117608 ,","place":["Singapore"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2688-736X","authenticated-orcid":false,"given":"Michael J.","family":"Kuba","sequence":"additional","affiliation":[{"name":"University of Naples Federico II 3 Department of Biology , , Via Cintia 26, 80126 Naples ,","place":["Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9658-5597","authenticated-orcid":false,"given":"Tamar","family":"Gutnick","sequence":"additional","affiliation":[{"name":"Haus des Meeres-Aqua Terra Zoo 4 , 1060 Vienna ,","place":["Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel","family":"Abed-Navandi","sequence":"additional","affiliation":[{"name":"Haus des Meeres-Aqua Terra Zoo 4 , 1060 Vienna ,","place":["Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5248-1043","authenticated-orcid":false,"given":"Cecilia","family":"Laschi","sequence":"additional","affiliation":[{"name":"College of Design and Engineering, National University of Singapore 1 Department of Mechanical Engineering , , Singapore 117575 ,","place":["Singapore"]},{"name":"Advanced Robotics Centre, National University of Singapore 2 , Singapore 117608 ,","place":["Singapore"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"237","published-online":{"date-parts":[[2026,11,5]]},"reference":[{"key":"2026110516014854900_JEB252825C1","doi-asserted-by":"publisher","first-page":"45","DOI":"10.1016\/j.tree.2018.10.010","article-title":"Grow smart and die young: why did cephalopods evolve intelligence?","volume":"34","author":"Amodio","year":"2019","journal-title":"Trends Ecol. Evol."},{"key":"2026110516014854900_JEB252825C2","doi-asserted-by":"publisher","first-page":"396","DOI":"10.1038\/nature22382","article-title":"A wet-tolerant adhesive patch inspired by protuberances in suction cups of octopi","volume":"546","author":"Baik","year":"2017","journal-title":"Nature"},{"key":"2026110516014854900_JEB252825C3","first-page":"39","article-title":"Evaluation of the capture efficiency and size selectivity of four pot types in the prospective fishery for North Pacific giant octopus (Enteroctopus dofleini)","volume":"108","author":"Barry","year":"2010","journal-title":"Fish. Bull."},{"key":"2026110516014854900_JEB252825C4","doi-asserted-by":"publisher","first-page":"20170101","DOI":"10.1098\/rsif.2017.0101","article-title":"Fundamentals of soft robot locomotion","volume":"14","author":"Calisti","year":"2017","journal-title":"J. R. Soc. Interface"},{"key":"2026110516014854900_JEB252825C5","doi-asserted-by":"publisher","first-page":"1800","DOI":"10.3390\/app13031800","article-title":"Robotics in Search and Rescue (SAR) operations: an ethical and design perspective framework for response phase","volume":"13","author":"Chitikena","year":"2023","journal-title":"Appl. Sci."},{"key":"2026110516014854900_JEB252825C6","doi-asserted-by":"publisher","first-page":"035003","DOI":"10.1088\/1748-3190\/10\/3\/035003","article-title":"Bioinspired locomotion and grasping in water: the soft eight-arm OCTOPUS robot","volume":"10","author":"Cianchetti","year":"2015","journal-title":"Bioinspir. Biomim."},{"key":"2026110516014854900_JEB252825C7","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1177\/0023677215580006","article-title":"Guidelines for the care and welfare of cephalopods in research \u2013a consensus based on an initiative by CephRes, FELASA and the Boyd Group","volume":"49","author":"Fiorito","year":"2015","journal-title":"Lab. Anim."},{"key":"2026110516014854900_JEB252825C8","doi-asserted-by":"publisher","first-page":"jeb245295","DOI":"10.1242\/jeb.245295","article-title":"Biomechanics, motor control and dynamic models of the soft limbs of the octopus and other cephalopods","volume":"226","author":"Flash","year":"2023","journal-title":"J. Exp. Biol."},{"key":"2026110516014854900_JEB252825C9","doi-asserted-by":"crossref","first-page":"195","DOI":"10.1007\/978-981-99-0589-8_6","article-title":"Ruin search and rescue robot","volume-title":"Special Robot Technology","author":"Guo","year":"2023"},{"key":"2026110516014854900_JEB252825C10","doi-asserted-by":"publisher","first-page":"7297","DOI":"10.1523\/JNEUROSCI.16-22-07297.1996","article-title":"Organization of octopus arm movements: a model system for studying the control of flexible arms","volume":"16","author":"Gutfreund","year":"1996","journal-title":"J. Neurosci."},{"key":"2026110516014854900_JEB252825C11","doi-asserted-by":"publisher","first-page":"R1083","DOI":"10.1016\/j.cub.2023.08.094","article-title":"Cephalopod behaviour","volume":"33","author":"Gutnick","year":"2023","journal-title":"Curr. Biol."},{"key":"2026110516014854900_JEB252825C12","doi-asserted-by":"publisher","first-page":"1667","DOI":"10.1109\/LRA.2022.3140812","article-title":"Snake robot gripper module for search and rescue in narrow spaces","volume":"7","author":"Han","year":"2022","journal-title":"IEEE Robot. Autom. Lett."},{"key":"2026110516014854900_JEB252825C13","doi-asserted-by":"publisher","first-page":"035001","DOI":"10.1088\/1748-3190\/10\/3\/035001","article-title":"Stereotypical reaching movements of the octopus involve both bend propagation and arm elongation","volume":"10","author":"Hanassy","year":"2015","journal-title":"Bioinspir. Biomim."},{"key":"2026110516014854900_JEB252825C14","doi-asserted-by":"publisher","first-page":"R887","DOI":"10.1016\/j.cub.2012.09.001","article-title":"An embodied view of octopus neurobiology","volume":"22","author":"Hochner","year":"2012","journal-title":"Curr. Biol."},{"key":"2026110516014854900_JEB252825C15","doi-asserted-by":"publisher","first-page":"909192","DOI":"10.3389\/fmars.2022.909192","article-title":"The evolution of predator avoidance in cephalopods: a case of brain over brawn?","volume":"9","author":"Jaitly","year":"2022","journal-title":"Front. Mar. Sci."},{"key":"2026110516014854900_JEB252825C16","doi-asserted-by":"publisher","first-page":"865","DOI":"10.1038\/s41586-025-09379-z","article-title":"In situ light-field imaging of octopus locomotion reveals simplified control","volume":"646","author":"Katija","year":"2025","journal-title":"Nature"},{"key":"2026110516014854900_JEB252825C17","doi-asserted-by":"publisher","first-page":"831","DOI":"10.1002\/jmor.10548","article-title":"The arrangement and function of octopus arm musculature and connective tissue","volume":"268","author":"Kier","year":"2007","journal-title":"J. Morphol."},{"key":"2026110516014854900_JEB252825C18","first-page":"141","article-title":"Muscle arrangement, function and specialization in recent coleoids","author":"Kier","year":"2003"},{"key":"2026110516014854900_JEB252825C35","doi-asserted-by":"publisher","first-page":"12002","DOI":"10.1088\/1757-899x\/1261\/1\/012002","article-title":"Embodied Intelligence in soft robotics: joys and sorrows","volume":"1261","author":"Laschi","year":"2022","journal-title":"IOP Conf. Ser.: Mater. Sci. Eng."},{"key":"2026110516014854900_JEB252825C19","doi-asserted-by":"publisher","first-page":"1195","DOI":"10.1016\/j.cub.2015.02.064","article-title":"Arm coordination in octopus crawling involves unique motor control strategies","volume":"25","author":"Levy","year":"2015","journal-title":"Curr. Biol."},{"key":"2026110516014854900_JEB252825C20","doi-asserted-by":"publisher","first-page":"131","DOI":"10.1016\/j.cobeha.2017.06.008","article-title":"Cephalopod complex cognition","volume":"16","author":"Mather","year":"2017","journal-title":"Curr. Opin. Behav. Sci."},{"key":"2026110516014854900_JEB252825C21","doi-asserted-by":"publisher","first-page":"921","DOI":"10.1038\/s44222-025-00344-z","article-title":"Energy-saving movement strategies in animals and plants for robot design","volume":"3","author":"Mazzolai","year":"2025","journal-title":"Nat. Rev. Bioeng"},{"key":"2026110516014854900_JEB252825C22","volume-title":"Anti-Predator Behavior of Octopus vulgaris","author":"Miao","year":"2016"},{"key":"2026110516014854900_JEB252825C23","doi-asserted-by":"publisher","first-page":"4928","DOI":"10.1109\/TAES.2022.3217746","article-title":"Hyper-redundant manipulators for operations in confined space: typical applications, key technologies, and grand challenges","volume":"58","author":"Mu","year":"2022","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"2026110516014854900_JEB252825C24","doi-asserted-by":"publisher","first-page":"4767","DOI":"10.1016\/j.cub.2024.09.007","article-title":"Repeating ultrastructural motifs provide insight into the organization of the octopus arm nervous system","volume":"34","author":"Neacsu","year":"2024","journal-title":"Curr. Biol."},{"key":"2026110516014854900_JEB252825C25","doi-asserted-by":"publisher","first-page":"1069","DOI":"10.1242\/jeb.115915","article-title":"Octopus arm movements under constrained conditions: adaptation, modification and plasticity of motor primitives","volume":"218","author":"Richter","year":"2015","journal-title":"J. Exp. Biol."},{"key":"2026110516014854900_JEB252825C26","doi-asserted-by":"publisher","first-page":"162","DOI":"10.1111\/brv.12651","article-title":"How intelligent is a cephalopod? Lessons from comparative cognition","volume":"96","author":"Schnell","year":"2021","journal-title":"Biol. Rev."},{"key":"2026110516014854900_JEB252825C27","doi-asserted-by":"crossref","DOI":"10.1007\/978-94-017-2468-5","volume-title":"Octopus: Physiology and Behaviour of an Advanced Invertebrate","author":"Wells","year":"1978"},{"key":"2026110516014854900_JEB252825C28","doi-asserted-by":"publisher","first-page":"213","DOI":"10.1080\/21642583.2018.1477634","article-title":"Autonomous robots for harsh environments: a holistic overview of current solutions and ongoing challenges","volume":"6","author":"Wong","year":"2018","journal-title":"Syst. Sci. Control Eng."},{"key":"2026110516014854900_JEB252825C29","doi-asserted-by":"publisher","first-page":"eadh7852","DOI":"10.1126\/scirobotics.adh7852","article-title":"Octopus-inspired sensorized soft arm for environmental interaction","volume":"8","author":"Xie","year":"2023","journal-title":"Sci. Robot."},{"key":"2026110516014854900_JEB252825C30","first-page":"1","article-title":"Evaluation of internal curvature on suction cup performance","author":"Xin","year":"2025"},{"key":"2026110516014854900_JEB252825C31","doi-asserted-by":"publisher","first-page":"2308829","DOI":"10.1002\/adma.202308829","article-title":"Multimodal soft robotic actuation and locomotion","volume":"36","author":"Yao","year":"2024","journal-title":"Adv. Mater."},{"key":"2026110516014854900_JEB252825C32","volume-title":"The Anatomy of the Nervous System of Octopus vulgaris","author":"Young","year":"1971"},{"key":"2026110516014854900_JEB252825C33","doi-asserted-by":"publisher","first-page":"393","DOI":"10.2989\/025776198784126287","article-title":"The evolution of coleoid cephalopods and their present biodiversity and ecology","volume":"20","author":"Young","year":"1998","journal-title":"South Afr. J. Mar. Sci."},{"key":"2026110516014854900_JEB252825C34","doi-asserted-by":"publisher","first-page":"60","DOI":"10.3389\/fncom.2013.00060","article-title":"Kinematic decomposition and classification of octopus arm movements","volume":"7","author":"Zelman","year":"2013","journal-title":"Front. Comput. Neurosci."}],"container-title":["Journal of Experimental Biology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.biologists.com\/jeb\/article-pdf\/doi\/10.1242\/jeb.252825\/3723659\/jeb252825.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/journals.biologists.com\/jeb\/article-pdf\/doi\/10.1242\/jeb.252825\/3723659\/jeb252825.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,11,5]],"date-time":"2026-11-05T21:01:54Z","timestamp":1793912514000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.biologists.com\/jeb\/article\/229\/21\/jeb252825\/373328\/Overcoming-environmental-constraints-octopus-uses"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,11,1]]},"references-count":35,"journal-issue":{"issue":"21","published-print":{"date-parts":[[2026,11,1]]}},"URL":"https:\/\/doi.org\/10.1242\/jeb.252825","relation":{},"ISSN":["0022-0949","1477-9145"],"issn-type":[{"value":"0022-0949","type":"print"},{"value":"1477-9145","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,11,1]]},"article-number":"jeb252825"}}