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Updated: Jul 30, 2026
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Controlling Flow Speeds of Microtubule-Based 3D Active Fluids Using Temperature
Published on: November 26, 2019
Vortex formation by active agents as a model for Daphnia swarming
Jürgen Vollmer1, Attila Gergely Vegh, Christoph Lange
1Fachbereich Physik, Philipps-Universität Marburg, Renthof 6, D-35032 Marburg, Germany. juergen.vollmer@physik.uni-marburg.de
Summary
We developed a model for Daphnia swarming, finding that a vortex forms only with intermediate propulsion strength. This research identifies key parameters influencing collective motion in aquatic organisms.
Area of Science:
- Physics
- Biology
- Collective behavior
Background:
- Daphnia exhibit complex collective behaviors, including swarming.
- Understanding the mechanisms driving these behaviors is crucial for ecological and biological studies.
Purpose of the Study:
- To propose a self-propelled particle model for Daphnia swarming.
- To investigate the conditions leading to vortex formation in Daphnia aggregations.
- To identify key parameters governing collective motion.
Main Methods:
- Developed a self-propelled particle model incorporating mutual repulsion and attraction to a center.
- Analyzed the phase diagram and state transitions (vortex vs. no vortex).
- Utilized linear stability analysis to study individual swimmer motion and phase boundaries.
Main Results:
- A vortex state is observed only for an intermediate range of propulsion strength.
- The study maps out phase transitions between states with and without vortex formation.
- Key parameters influencing collective motion characteristics were identified.
Conclusions:
- The proposed model successfully captures vortex formation in Daphnia swarming under specific propulsion conditions.
- Linear stability analysis provides insights into the mechanisms underlying collective motion and phase transitions.
- This work offers a framework for understanding and predicting collective behaviors in biological systems.
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