Related Experiment Video
Updated: Mar 8, 2026
03:54
Observation of Photobehavior in Chlamydomonas reinhardtii
Published on: May 6, 2022
4.7K
Light-Dependent Switching of Circling Handedness in Microswimmer Navigation
Zhao Wang1, Samuel A Bentley2, Jiawei Li1
1The University of Hong Kong, Department of Mechanical Engineering, Pokfulam Road, Hong Kong, China.
Physical Review Letters
|March 6, 2026
Summary
Microswimmers like Chlamydomonas reinhardtii change swimming direction based on light intensity. This involves altering flagellar beating, crucial for navigation and exploring light fields.
Area of Science:
- Microbiology
- Biophysics
- Cell Biology
Background:
- Microorganisms navigate environments using trajectory modulation.
- Light cues influence microorganism behavior and movement.
Purpose of the Study:
- To investigate how Chlamydomonas reinhardtii navigates using light cues.
- To elucidate the role of flagellar beating in Chlamydomonas trajectory control.
Main Methods:
- High-speed imaging of Chlamydomonas reinhardtii.
- Hydrodynamic modeling of microswimmer trajectories.
- Analysis of flagellar beat parameters under varying light intensities.
Main Results:
- Chlamydomonas reinhardtii switches swimming handedness (clockwise/counterclockwise) based on light intensity.
- Light-dependent modulation of flagellar beat extension, phase, and beat plane orientation observed.
- Beat plane reorientation identified as critical for orthogonal swimming and curvature modulation.
Conclusions:
- Beat plane reorientation is a novel mechanism for curvature control in microswimmers.
- Chlamydomonas uses light-dependent beat plane changes for navigation and exploration.
- This mechanism enables dynamic transitions between global exploration and localized searching.
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