Mapping the stereotyped behaviour of freely-moving fruit flies
This provides a systematic approach for behavioral scientists to analyze and compare complex animal movements, though it is incremental in applying data-driven methods to a known problem.
The researchers tackled the problem of characterizing animal behavior by developing a method to map behavioral space from postural movement data, finding that six fruit fly species exhibit over one hundred stereotyped behaviors organized hierarchically, along with non-stereotyped actions, and used this to systematically identify subtle differences between closely-related species.
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.