Hydrodynamic phase-locking of swimming microorganisms

TL;DR

This study demonstrates that hydrodynamic forces alone can cause synchronization of swimming microorganisms' flagella, driven by geometric asymmetry, influencing their energy efficiency and phase-locking behavior.

Contribution

The paper introduces a simplified two-sheet model showing hydrodynamic phase-locking arises solely from geometric asymmetry, advancing understanding of microorganism synchronization mechanisms.

Findings

Hydrodynamic forces induce phase-locking in microorganisms.

Geometric asymmetry determines phase evolution and synchronization.

Microorganisms can minimize or maximize energy dissipation through phase-locking.

Abstract

Some microorganisms, such as spermatozoa, synchronize their flagella when swimming in close proximity. Using a simplified model (two infinite, parallel, two-dimensional waving sheets), we show that phase-locking arises from hydrodynamics forces alone, and has its origin in the front-back asymmetry of the geometry of their flagellar waveform. The time-evolution of the phase difference between co-swimming cells depends only on the nature of this geometrical asymmetry, and microorganisms can phase-lock into conformations which minimize or maximize energy dissipation.