Navigated and Unguided Modes of Population Expansion (video) University of California - San Diego Share Print E-Mail Loading video... Caption The radial density profile is shown for the navigated expansion process taken by chemotactic bacteria (top panel) and unguided expansion process taken by motile but non-chemotactic bacteria (bottom panel). Each is inoculated at the center of a soft-agar plate at time t=0. The density bulge at the leading front of navigated expansion is the feature seen distinctively in the photos of Fig. 1A as the "swarm ring." Credit Hwa Lab, UC San Diego Usage Restrictions Must be used in conjunction with Hwa Lab papers in Nature. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.