Zebrafish response to robotic fish: preference experiments on isolated individuals and small shoals

TLDR

Bioinspired robots mimic live fish in appearance and function, yet experimental evidence of their ecological integration remains scarce. The study aims to determine whether a robotic fish can modulate zebrafish spontaneous behaviour. Researchers engineered a robotic fish and tested its influence on zebrafish in a two‑choice preference assay. The robotic fish attracted isolated zebrafish and small shoals but never surpassed conspecific preference; its undulating motion increased attractiveness, providing first evidence that engineered robots can influence zebrafish behaviour and offering a tool to study social dynamics.

Abstract

Recently developed bioinspired robots imitate their live counterparts in both aspect and functionality. Nevertheless, whether these devices can be integrated within the ecological niche inspiring their design is seldom tested experimentally. An elemental research question concerns the feasibility of modulating spontaneous behaviour of animal systems through bioinspired robotics. The following study explores the possibility of engineering a robotic fish capable of influencing the behaviour of live zebrafish (Danio rerio) in a dichotomous preference test. While we observe that the preference for the robotic fish never exceeds the preference for a conspecific, our data show that the robot is successful in attracting both isolated individuals and small shoals and that such capability is influenced by its bioinspired features. In particular, we find that the robot's undulations enhance its degree of attractiveness, despite the noise inherent in the actuation system. This is the first experimental evidence that live zebrafish behaviour can be influenced by engineered robots. Such robotic platforms may constitute a valuable tool to investigate the bases of social behaviour and uncover the fundamental determinants of animal functions and dysfunctions.