Optimal searching behaviour generated intrinsically by the central pattern generator for locomotion
- Marine Biological Association of the United Kingdom, United Kingdom
- University of Cambridge, United Kingdom
- Universidad de Buenos Aires, Argentina
Abstract
Efficient searching for resources such as food by animals is key to their survival. It has been proposed that diverse animals from insects to sharks and humans adopt searching patterns that resemble a simple Lévy random walk, which is theoretically optimal for 'blind foragers' to locate sparse, patchy resources. To test if such patterns are generated intrinsically, or arise via environmental interactions, we tracked free-moving Drosophila larvae with (and without) blocked synaptic activity in the brain, suboesophageal ganglion (SOG) and sensory neurons. In brain-blocked larvae we found that extended substrate exploration emerges as multi-scale movement paths similar to truncated Lévy walks. Strikingly, power-law exponents of brain/SOG/sensory-blocked larvae averaged 1.96, close to a theoretical optimum (µ ≅ 2.0) for locating sparse resources. Thus, efficient spatial exploration can emerge from autonomous patterns in neural activity. Our results provide the strongest evidence so far for the intrinsic generation of Lévy-like movement patterns.
Data availability
All data generated and analysed in this study are available in Dryad (doi: 10.5061/dryad.7m0cfxpq0). Results from analysis are also included in the manuscript and supporting files.
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Data from: Optimal searching behaviour generated intrinsically by the central pattern generator for locomotionDryad Digital Repository, doi:10.5061/dryad.7m0cfxpq0.
Article and author information
Author details
Funding
Wellcome (105568/Z/14/Z)
- Jimena Berni
Royal Society (105568/Z/14/Z)
- Jimena Berni
Consejo Nacional de Investigaciones Científicas y Técnicas (PICT 20121578)
- Violeta Medan
Natural Environment Research Council (Oceans 2025 Strategic Research Programme)
- David W Sims
Marine Biological Association (Senior Research Fellowship)
- David W Sims
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Sims et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Optimal searching behaviour generated intrinsically by the central pattern generator for locomotion
eLife 8:e50316.
https://doi.org/10.7554/eLife.50316
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