The Bacterial System: Evolution Everywhere: Bacteria on surfaces grow into communities called biofilms. Some bacteria, including Cellulophaga lytica, have the unusual ability to self- assemble into crystalline biofilms where the cells are precisely aligned and closely packed. The structural color associated with these biofilms is a consequence light interacting with the ordered bacteria. This piece is composed of 8X optical images of C. lytica biofilms grown under various conditions. It is a reminder that bacteria are wherever people are and in some places that people have yet to be. Contributors: Claretta J. Sullivan, Kennedy Brown