Dynamics of pattern formation and emergence of swarming in C. elegans

  1. Esin Demir
  2. Y Ilker Yaman
  3. Mustafa Basaran
  4. Askin Kocabas  Is a corresponding author
  1. Koç Üniversity, Turkey
  2. Koç University, Turkey

Abstract

Many animals collectively form complex patterns to tackle environmental difficulties. Several biological and physical factors, such as animal motility, population densities, and chemical cues, play significant roles in this process. However, very little is known about how sensory information interplays with these factors and controls the dynamics of pattern formation. Here, we study the direct relation between oxygen sensing, pattern formation, and emergence of swarming in active C. elegans aggregates. We find that when thousands of animals gather on food, bacteria-mediated decrease in oxygen level slows down the animals and triggers motility-induced phase separation. Three coupled factors—bacterial accumulation, aerotaxis, and population density—act together and control the entire dynamics. Furthermore, we find that biofilm-forming bacterial lawns including Bacillus Subtilis and Pseudomonas aeruginosa strongly alter the collective dynamics due to the limited diffusibility of bacteria. Additionally, our theoretical model captures behavioral differences resulting from genetic variations and oxygen sensitivity.

Data availability

All data generated or analyzed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Esin Demir

    Physics, Koç Üniversity, Istanbul, Turkey
    Competing interests
    The authors declare that no competing interests exist.
  2. Y Ilker Yaman

    Physics, Koç University, Istanbul, Turkey
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4094-616X
  3. Mustafa Basaran

    Physics, Koç Üniversity, Istanbul, Turkey
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1895-254X
  4. Askin Kocabas

    Physics, Koç Üniversity, Istanbul, Turkey
    For correspondence
    akocabas@ku.edu.tr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6930-1202

Funding

European Molecular Biology Organization (IG 3275)

  • Askin Kocabas

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

Reviewing Editor

  1. Sandeep Krishna, National Centre for Biological Sciences­‐Tata Institute of Fundamental Research, India

Publication history

  1. Received: October 16, 2019
  2. Accepted: April 5, 2020
  3. Accepted Manuscript published: April 6, 2020 (version 1)
  4. Version of Record published: May 6, 2020 (version 2)

Copyright

© 2020, Demir 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. Esin Demir
  2. Y Ilker Yaman
  3. Mustafa Basaran
  4. Askin Kocabas
(2020)
Dynamics of pattern formation and emergence of swarming in C. elegans
eLife 9:e52781.
https://doi.org/10.7554/eLife.52781

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