An international research team has unveiled significant findings regarding the locomotion of elongated amphibious animals. The researchers developed an innovative model that explains how elongated amphibious animals—such as eels—coordinate movement both in water and on land.
This collaborative effort, supported by the Human Frontier Science Program , involved researchers from the BioRob lab at EPFL in Switzerland , the Ishiguro Lab at Tohoku University in Japan , and the Standen Lab at University of Ottawa .
Emily Standen , Associate Professor at uOttawa's Faculty of Science and one of the lead Principal Investigators, led the biological side of the research. "Our study introduces a new model to explain the control of locomotion in elongated amphibious animals," she says. "We aim to deepen our understanding of the neuromotor control systems used by animals that can adapt their movements between aquatic and terrestrial environments."
The research, which has spanned multiple years, involved a comprehensive approach combining simulation modeling at Tohoku University, robotics testing at EPFL, and animal observation at the University of Ottawa. "In my lab, we observed eels to better understand their motor control systems and observe how brain signals, local spinal pattern generators and sensory feedback systems influence undulatory locomotion," Professor Standen explains. "By using eels as a living model, we were able to guide the simulation and robotics models with biological data."
The models in this study show that basic components of the motor system, like coordination in the nervous system, as well as pressure feedback and stretch feedback, allow for redundant coordination during swimming. This redundancy and the capacity of stretch feedback to allow the exploitation of heterogeneity in the environment to help move forward, may explain why elongated fish like the eel and lamprey can move in terrestrial environments. "These animals are remarkably resilient," she notes. "Our models point to sensory feedback as the key to allowing them to maintain their locomotor performance."
Bio-Inspired Robotics
Beyond animal biology, the findings could help engineers design flexible robots for challenging environments. "This research provides new ways of understanding neuromotor control in animals, which can have far-reaching implications for both scientific research and technological advancements," says Professor Standen. Imagine robots that crawl, slither, or swim through tight spaces, using nature's engineering to stay flexible and strong.
The study, " Multisensory feedback makes swimming circuits robust against spinal transection and enables terrestrial crawling in elongate fish ," is now published in the Proceedings of the National Academy of Sciences (PNAS). It's a leap forward in understanding movement and could inspire innovative robot designs in the future.
