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bioRxiv · 10.64898/2026.04.21.718724

PALAEOROBOTICS UNCOVERS DEVASTATING MAMMALIAN TAIL STRIKE DYNAMICS

Le Verger, K.·Allione, F.·Wang, B.·Weisse, B.·Ijspeert, A.·Sanchez-Villagra, M. R.·Scheyer, T. M.·Jusufi, A.
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Abstract

Extant animals occupy only a fraction of evolutionary design space, leaving many extinct morphologies without living analogues for functional testing. We combined comparative anatomy of 32 glyptodont species with a life-sized palaeorobotic tail rig to determine strike severity in club-tailed giant from the Pleistocene megafauna Doedicurus. The robophysical model, informed by fossil geometry and inertia, matched simulated fossil-tail collision momentum (98-105%) and generated peak forces of 81.1 kN at 6.4 m{middle dot}s-{superscript 1}, with an impulse of 427 N{middle dot}s, far exceeding equine extremity fracture forces. Peak force scaled near-linearly with strike velocity, implying [~]183 kN at projected top speed of 15 m{middle dot}s-{superscript 1}. Measurements suggest Doedicurus delivered high-severity strikes, supporting antipredator defence as primary selective driver of extreme tail weaponization, and establish palaeorobotic validation of extinct animal biomechanics.

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Le Verger, K., Allione, F., Wang, B., Weisse, B., Ijspeert, A., Sanchez-Villagra, M. R., Scheyer, T. M., Jusufi, A.. 2026-04-23. PALAEOROBOTICS UNCOVERS DEVASTATING MAMMALIAN TAIL STRIKE DYNAMICS. https://doi.org/10.64898/2026.04.21.718724

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