Bacterial tracking of motile algae assisted by algal cell's vorticity field

Janos Tobias Locsei; Timothy J Pedley

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arXiv · 0806.0744

Bacterial tracking of motile algae assisted by algal cell's vorticity field

Janos Tobias Locsei·Timothy J Pedley

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Abstract

Previously published experimental work by other authors has shown that certain motile marine bacteria are able to track free swimming algae by executing a zigzag path and steering toward the algae at each turn. Here, we propose that the apparent steering behaviour could be a hydrodynamic effect, whereby an algal cell's vorticity and strain-rate fields rotate a pursuing bacterial cell in the appropriate direction. Using simplified models for the bacterial and algal cells, we numerically compute the trajectory of a bacterial cell and demonstrate the plausibility of this hypothesis.

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Janos Tobias Locsei, Timothy J Pedley. 2008-06-04. Bacterial tracking of motile algae assisted by algal cell's vorticity field. https://arxiv.org/abs/0806.0744

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