In my first microbiology class in 1968, Richard Wodzinki opened his first lecture with "Wodzinski's Laws of Bacteriology. " Those laws were (1) Bacteria are very very small, (2) Bacteria are our friends, and (3) Bacteria always have the last word. These simple statements motivated a career of curiosity, and started me on a wild ride of discovery with my miniscule colleagues. The realization that an entity so tiny could mediate critical ecological p- cesses observed across scales of kilometers begs for an explanation of how populations and communities are distributed within those large spaces....