Statistical Mobility of Multicellular Colonies of Flagellated Swimming Cells

TL;DR

This paper models the stochastic hydrodynamics of multicellular colonies of flagellated cells, linking individual cell dynamics to colony movement and morphology, with detailed formulas for rosette and chain-like structures.

Contribution

It introduces autoregressive stochastic models for flagellar force dynamics and derives effective transport properties for various colony shapes.

Findings

Quantitative models for colony mobility based on cell-level variability.

Formulas for dynamics of planar colony morphologies.

Effective transport properties for rosette and chain-like colonies.

Abstract

We study the stochastic hydrodynamics of colonies of flagellated swimming cells, typified by multicellular choanoflagellates, which can form both rosette and chainlike shapes. The objective is to link cell-scale dynamics to colony-scale dynamics for various colonial morphologies. Via autoregressive stochastic models for the cycle-averaged flagellar force dynamics and statistical models for demographic cell-to-cell variability in flagellar properties and placement, we derive effective transport properties of the colonies, including cell-to-cell variability. We provide the most quantitative detail on disclike geometries to model rosettes, but also present formulas for the dynamics of general planar colony morphologies, which includes planar chain-like configurations.