Bacteria, such as these Shewanella putrefaciens cells growing on iron oxide particles, use chemical signals to coordinate biofilm formation and other community-level behaviors.
Credit or Source: DOE Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory. See EMSL’s Flickr gallery at www.flickr.com/photos/emsl/
U.S. DOE 2012. Biosystems Design: Report from the July 2011 Workshop, DOE/SC-0141, U.S. Department of Energy Office of Science. (p. 12) (PDF)