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bioRxiv · 10.1101/2024.12.31.630952

Scaly-Tail Organ Enhances Static Stability during Pel's Scaly-tailed Flying Squirrels' Arboreal Locomotion

Schulz, A. K.·Chellapurath, M.·Khandelwal, P.·Rezaei, S.·Merker, S.·Jusufi, A.
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Abstract

Scaly-tailed squirrels (Anomaluridae) are one of the least studied mammalian families. Their namesake is due to a peculiar and unique scaly-tail organ extruding from the caudal vertebrate that has been predicted to help reduce skidding. This study investigates the function of the scaly-tail organ found in Anomalurus pelii, investigating its potential role in enhancing arboreal locomotion. As these animals glide from tree to tree in a habitat abundant with smooth-bark trees, we hypothesize that the scaly-tail organ assists with friction enhancement in their native smooth-bark habitat. Through a combination of analyses using mathematical and physical models for experimental validation, we explore whether the scaly-tail organ could improve the sliding and overturning stability during perching. Our experimental results showed that the scaly-tail organ can act as a skid-reduction mechanism by enhancing substrate engagement on intermediate roughness substrates by 58%. Mathematical models showed the scaly-tail organ enhances overturning stability by acting as an additional support point. Our model showed that the scaly-tailed squirrel can reach up to 82.5{whitebullet} inclination without claw force; however, without scales, it reduces to 79.6{whitebullet}. Overall, this research highlights the functional significance of scaly-tail organs in adaptations in scaly-tailed flying squirrels and contributes to our understanding of their locomotion strategies and environmental stresses. Our study also provides insights into innovative perching mechanisms for robots operating in arboreal environments.

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Schulz, A. K., Chellapurath, M., Khandelwal, P., Rezaei, S., Merker, S., Jusufi, A.. 2025-01-02. Scaly-Tail Organ Enhances Static Stability during Pel's Scaly-tailed Flying Squirrels' Arboreal Locomotion. https://doi.org/10.1101/2024.12.31.630952

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