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  • Navigating Nature's Terrain: Jumping Performance Robust to Substrate Moisture and Roughness by Blackspotted Rockskippers ( Entomacrodus striatus )

This content will become publicly available on January 29, 2026

Title: Navigating Nature's Terrain: Jumping Performance Robust to Substrate Moisture and Roughness by Blackspotted Rockskippers ( Entomacrodus striatus )
ABSTRACT Escape responses are vital for the survival of prey. The high speeds and accelerations needed to evade predators successfully require exerting forces on the environment. Unlike water, terrestrial habitats can vary in ways that constrain the forces applied, requiring animals to adjust their behavior in response to variable conditions. We evaluated the terrestrial jumping of an amphibious fish, the blackspotted rockskipper (Entomacrodus striatus), to determine if substrate roughness and wetness influence jumping performance. We predicted that rockskippers would produce a greater force output as substrate roughness increased and wetness decreased. Using a novel waterproof force plate capable of detecting millinewton loads, we collected ground reaction forces from rockskippers jumping on wet and dry sandpapers of varying grits. We also used micro‐CT scans to quantify muscle mass as a relative fraction of body mass to determine if these jumps could be performed without power amplification. Mixed‐model analysis of jumps revealed significantly higher maximum horizontal forces, jump duration, and maximum power on dry versus wet substrates, but no effect of substrate roughness. However, the final jump outcomes (takeoff speed and angle) were unaffected. Peak jump power was within the range of typical fish muscle. Thus, these fish display a jumping behavior which is robust to substrate property variation.  more » « less
Award ID(s):
1929900
PAR ID:
10570086
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Journal of Experimental Zoology Part A: Ecological and Integrative Physiology
ISSN:
2471-5638
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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