Mapping the stereotyped behaviour of freely-moving fruit flies

TL;DR

This paper presents a method to map and classify the behavioral repertoire of freely-moving fruit flies, revealing a hierarchy of stereotyped actions and subtle interspecies differences using postural movement data.

Contribution

It introduces a novel approach for organizing and comparing animal behaviors based solely on movement data, applicable across multiple species.

Findings

Six drosophilid species exhibit hierarchically-organized stereotyped behaviors.

Over one hundred stereotyped behaviors identified across species.

Subtle behavioral differences systematically characterized between closely-related species.

Abstract

Most animals possess the ability to actuate a vast diversity of movements, ostensibly constrained only by morphology and physics. In practice, however, a frequent assumption in behavioral science is that most of an animal's activities can be described in terms of a small set of stereotyped motifs. Here we introduce a method for mapping the behavioral space of organisms, relying only upon the underlying structure of postural movement data to organize and classify behaviors. We find that six different drosophilid species each perform a mix of non-stereotyped actions and over one hundred hierarchically-organized, stereotyped behaviors. Moreover, we use this approach to compare these species' behavioral spaces, systematically identifying subtle behavioral differences between closely-related species.