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This content will become publicly available on February 7, 2026

Title: Exploring the swimming performance and the physical mechanisms of Tomopteris locomotion
Abstract Tomopterids are mesmerizing holopelagic swimmers. They use two modes of locomotion simultaneously: drag-based metachronal paddling and bodily undulation.Tomopterishas two rows of flexible, leg-like parapodia positioned on opposite sides of its body. Each row metachronally paddles out of phase to the other. Both paddling behaviors occur in concert with a lateral bodily undulation. However, when looked at independently, each mode appears in tension with the other. The direction of the undulatory wave is opposite of what one may expect for forward (FWD) swimming and appears to actively work act against the direction of swimming initiated by metachronal paddling. To investigate how these two modes of locomotion synergize to generate effective swimming, we created a self-propelled, fluid-structure interaction model of an idealizedTomopteris. We holistically explored swimming performance over a 3D mechanospace comprising parapodia length, paddling amplitude, and undulatory amplitude using a machine learning framework based on polynomial chaos expansions. Although undulatory amplitude minimally affected FWD swimming speeds, it helped mitigate the larger costs of transport that arise from either using more mechanically expensive (larger) paddling amplitudes and/or having longer parapodia.  more » « less
Award ID(s):
2320244 2410987
PAR ID:
10616598
Author(s) / Creator(s):
Publisher / Repository:
IOP Science
Date Published:
Journal Name:
Bioinspiration & Biomimetics
Volume:
20
Issue:
2
ISSN:
1748-3182
Page Range / eLocation ID:
026011
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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