Evaluating Evasion Strategies in Zebrafish Larvae

TL;DR

This study introduces a framework to identify the most likely evasion strategy in prey fish, revealing zebrafish larvae typically escape orthogonally to predator heading to maximize survival chances.

Contribution

The paper presents a comprehensive method to determine prey evasion strategies considering sensorimotor noise and biomechanical constraints, specifically applied to zebrafish larvae.

Findings

Zebrafish larvae escape orthogonal to predator heading.

Orthogonal escape maximizes distance from predators.

Biomechanical constraints influence escape strategy effectiveness.

Abstract

An effective evasion strategy allows prey to survive encounters with predators. Prey are generally thought to escape in a direction that is either random or serves to maximize the minimum distance from the predator. Here we introduce a comprehensive approach to determine the most likely evasion strategy among multiple hypotheses and the role of biomechanical constraints on the escape response of prey fish. Through a consideration of six strategies with sensorimotor noise and previous kinematic measurements, our analysis shows that zebrafish larvae generally escape in a direction orthogonal to the predator's heading. By sensing only the predator's heading, this orthogonal strategy maximizes the distance from fast-moving predators, and, when operating within the biomechanical constraints of the escape response, it provides the best predictions of prey behavior among all alternatives. This work demonstrates a framework for resolving the strategic basis of evastion in predator-prey interactions, which could be applied to a broad diversity of animals.