Micro-organism swimming: individual and collective behaviour

"Swimming micro-organisms are everywhere: inside people (sperm, gut bacteria) and outside (algae and bacteria in bioreactors, lakes, oceans). This talk will survey the fluid mechanics of micro-organism swimming, from the low Reynolds number locomotion of individuals to the not necessarily low Reynolds number flows that they collectively generate in suspensions. The survey for individuals will start from the analyses of Taylor and Lighthill in the 1950s and finish with the very recent demonstration that fluid mechanics alone is enough to coordinate the beating of multiple cilia into metachronal waves, at least on Volvox. The survey for suspensions will start from studies of gyrotaxis in the 1990s, go on to the coherent structures driven by cell swimming stresslets, discovered in the 2000s, and conclude with an attempt to develop a continuum model for relatively concentrated suspensions."

About the Speaker:
Professor Timothy John Pedley FRS, is a former G. I. Taylor Professor of Fluid Mechanics at the University of Cambridge. His principal research interest is the application of fluid mechanics to biology and medicine.  Prof. Pedley has pioneered the application of fluid mechanics to understanding biological phenomena. His best-known work includes the study of blood flow in arteries, flow–structure interactions in elastic tubes, flow and pressure drop in the lung, and the collective behaviour of swimming microorganisms.  His research has touched on issues of medical importance, including arterial bypass grafts, urine flow from kidneys to bladder, and the ventilation of premature infants. His work on microorganisms has application to plankton ecology.