Individual crop loads provide local control for collective food intake in ant colonies

  1. Efrat Esther Greenwald
  2. Lior Baltiansky
  3. Ofer Feinerman  Is a corresponding author
  1. Weizmann Institute of Science, Israel

Abstract

Nutritional regulation by ants emerges from a distributed process: food is collected by a small fraction of workers, stored within the crops of individuals, and spreads via local ant-to-ant interactions. The precise individual-level underpinnings of this collective regulation have remained unclear mainly due to difficulties in measuring food within ants' crops. Here we image fluorescent liquid food in individually tagged Camponotus sanctus ants, and track the real-time food flow from foragers to their gradually satiating colonies. We show how the feedback between colony satiation level and food inflow is mediated by individual crop loads; specifically, the crop loads of recipient ants control food flow rates, while those of foragers regulate the frequency of foraging-trips. Interestingly, these effects do not rise from pure physical limitations of crop capacity. Our findings suggest that the emergence of food intake regulation does not require individual foragers to assess the global state of the colony.

Article and author information

Author details

  1. Efrat Esther Greenwald

    Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot, Israel
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3614-8915
  2. Lior Baltiansky

    Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot, Israel
    Competing interests
    The authors declare that no competing interests exist.
  3. Ofer Feinerman

    Department of Physics of Complex Systems, Weizmann Institute of Science, Rehobot, Israel
    For correspondence
    ofer.feinerman@weizmann.ac.il
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4145-0238

Funding

Israel Science Foundation (833/15)

  • Ofer Feinerman

European Research Council (648032)

  • Ofer Feinerman

The Estate of Rachmiel Ramon Bloch

  • Ofer Feinerman

The Clore Foundation

  • Ofer Feinerman

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Iain D Couzin, Princeton University, United States

Publication history

  1. Received: September 3, 2017
  2. Accepted: February 19, 2018
  3. Accepted Manuscript published: March 6, 2018 (version 1)
  4. Version of Record published: March 21, 2018 (version 2)
  5. Version of Record updated: March 23, 2018 (version 3)

Copyright

© 2018, Greenwald 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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  1. Efrat Esther Greenwald
  2. Lior Baltiansky
  3. Ofer Feinerman
(2018)
Individual crop loads provide local control for collective food intake in ant colonies
eLife 7:e31730.
https://doi.org/10.7554/eLife.31730

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