Picture DNA on Facebook. The image above is a map of links between the genes of the mustard plant Arabidopsis thaliana. Genes involved in the same biological process are connected by lines: red for more certain links, blue for less certain links. "It's not unlike a social network," says biologist Seung Yon Rhee.

Credit: Insuk Lee, Michael Ahn, Edward Marcotte, Seung Yon Rhee, Carnegie Institution for Science