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Hydrodynamic schooling of flapping swimmers.
Alexander D Becker1, Hassan Masoud1, Joel W Newbolt1
1Applied Math Lab, Courant Institute, New York University, 251 Mercer Street, New York, New York 10012, USA.
Nature Communications
|October 7, 2015
Summary
Collective animal movement, like fish schools and bird flocks, emerges from flow-mediated interactions. Researchers found that fluid dynamics alone can create coordinated group locomotion, enhancing speed and saving energy.
Area of Science:
- Fluid dynamics
- Collective behavior
- Biophysics
Background:
- Animal groups like fish schools and bird flocks exhibit complex collective behaviors driven by interactions within generated flows.
- Understanding how individual movements lead to emergent group locomotion is a key challenge in biophysics.
Purpose of the Study:
- To investigate the role of flow-mediated interactions in the collective locomotion of multiple bodies.
- To identify distinct modes of group movement and their underlying mechanisms.
Main Methods:
- Experiments and simulations were conducted using arrays of flapping wings to study propulsion within a collective wake.
- Mathematical modeling was employed to capture the memory effects of the flow field.
Main Results:
- Distinct locomotion modes were observed, characterized by group swimming speed and spatial phase shifts between neighboring wings.
- Coexistence of slow and fast modes was found, corresponding to constructive and destructive wing-wake interactions.
- Group swimming demonstrated potential for enhanced speed and power savings.
Conclusions:
- Fluid dynamic interactions alone are sufficient to generate coherent collective locomotion in groups.
- The findings suggest a new framework for understanding the role of fluid flows in animal collective behaviors.
- A mathematical model highlights the importance of flow field memory in collective movement.
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