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arXiv · 1211.3272

Emergent Run-and-Tumble Behavior in a Simple Model of Chlamydomonas with Intrinsic Noise

Rachel R. Bennett·Ramin Golestanian
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Abstract

Recent experiments on the green alga Chlamydomonas that swims using synchronized beating of a pair of flagella have revealed that it exhibits a run-and-tumble behavior similar to that of bacteria such as E. Coli. Using a simple purely hydrodynamic model that incorporates a stroke cycle and an intrinsic Gaussian white noise, we show that a stochastic run-and-tumble behavior could emerge, due to the nonlinearity of the combined synchronization-rotation-translation dynamics. This suggests the intriguing possibility that the alga might exploit nonlinear mechanics---as opposed to sophisticated biochemical circuitry as used by bacteria---to control its behavior.

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Rachel R. Bennett, Ramin Golestanian. 2012-11-14. Emergent Run-and-Tumble Behavior in a Simple Model of Chlamydomonas with Intrinsic Noise. https://doi.org/10.1103/physrevlett.110.148102

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