Internal states drive nutrient homeostasis by modulating exploration-exploitation trade-off
Abstract
Internal states can profoundly alter the behavior of animals. A quantitative understanding of the behavioral changes upon metabolic challenges is key to a mechanistic dissection of how animals maintain nutritional homeostasis. We used an automated video tracking setup to characterize how amino acid and reproductive states interact to shape exploitation and exploration decisions taken by adult Drosophila melanogaster. We find that these two states have specific effects on the decisions to stop at and leave proteinaceous food patches. Furthermore, the internal nutrient state defines the exploration-exploitation trade-off: nutrient-deprived flies focus on specific patches while satiated flies explore more globally. Finally, we show that olfaction mediates the efficient recognition of yeast as an appropriate protein source in mated females and that octopamine is specifically required to mediate homeostatic postmating responses without affecting internal nutrient sensing. Internal states therefore modulate specific aspects of exploitation and exploration to change nutrient selection.
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Data from: Internal states drive nutrient homeostasis by modulating exploration-exploitation trade-offAvailable at Dryad Digital Repository under a CC0 Public Domain Dedication.
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Funding
Fundação para a Ciência e a Tecnologia (PTDC/BIA-BCM/118684/2010)
- Carlos Ribeiro
Human Frontier Science Program (RGP0022/2012)
- Aldo A Faisal
- Carlos Ribeiro
Champalimaud Foundation
- Verónica María Corrales-Carvajal
- Carlos Ribeiro
Fundação para a Ciência e a Tecnologia (Graduate Student Fellowship, SFRH/BD/51113/2010)
- Verónica María Corrales-Carvajal
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2016, Corrales-Carvajal 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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