2026-09-22T13:10:52Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/132681 2026-03-24 col_2142_5131 col_2142_16341 com_2142_5130 com_2142_8913 com_2142_8903

application/pdf en text Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-12-01 The student, Avalon Feiler, accepted the attached license on 2025-12-02 at 13:49. The student, Avalon Feiler, submitted this Thesis for approval on 2025-12-02 at 14:00. This Thesis was approved for publication on 2025-12-02 at 15:20. DSpace SAF Submission Ingestion Package generated from Vireo submission #23021 on 2026-02-19 at 18:46:30 Mechanically constrained stereotypy in agonid escape responses Feiler, Avalon 2025-12-02 Anderson, Philip Fuller, Becky Tan, Milton biomechanics armor eng In armor design, there is often a trade-off between protection and mobility—a balance that may influence the evolution of biological armor. In this study, I investigated whether the distinctive bony armor plates of Agonid fishes, specifically that of the grey starsnout poacher (Bathyagonus alascanus), impose mechanical constraints on movement. Focusing on the C-start escape response, I used high-speed video to quantify maximum body curvature and changes in lateral body length during the behavior. To connect scale morphology to flexibility, I measured the length of adjacent lateral scales from micro-computed tomography (µCT) scans of bent and straight specimens. The resulting bent-to-straight length (BSL) ratio served as a proxy for lateral surface compression and closely matched the lateral length changes observed in C-start trials. These findings suggest that flexibility is plausibly constrained by scale morphology, contributing to stereotyped escape responses, although the fish rarely use their full bending capacity. 2025-12 Thesis https://hdl.handle.net/2142/132681 Copyright 2025 Avalon Feiler Evolution Ecology Behavior Biology University of Illinois Urbana-Champaign M.S. Thesis