SGER: Motility, Mixing, and Multicellularity

University Of Arizona, Tucson AZ

Investigators

Abstract

The overall research goal of the collaboration in this SGER award is to dissect the physical problem of the coupling of motility with global transport and mixing. Conventionally, transport is viewed as dominated by the diffusion of molecular solutes, with advection playing a minor role. Yet, the collective dynamics of the flagella of motile microorganisms can generate spatially extended, often chaotic flows. These flows feature large Peclet numbers, stretching and folding; they may radically augment transport from that which is conventionally thought to govern these biological systems. Using two complementary complex biosystems, self-concentrated bacteria and colonial volvocalean algae, the group will quantify advection and mixing, together with spatial and temporal correlations of the flow dynamics, using particle imaging velocimetry (PIV) to track tracer particles and organisms. Investigating concurrently such superficially incommensurate systems should reveal fluid dynamical commonalities that apply far more generally. The experimental program will test recent theoretical analyses concerning these phenomena and guide in the development of appropriate many-body theories of these collective flows. Students working on the project will benefit by the interdisciplinarity within this new and rapidly-growing bio-microfluidics area of science.