Fig. 7.

Union of two nested matrices indicates possible host–phage interaction structure at larger, possibly macroevolutionary scales. In this figure, we selected two of the most nested studies and performed a union while presuming that there were no cross-infections of hosts by phages of the other study. In this case, E. coli and cyanobacteria were the host types. (A) Depiction of the original matrices. (B) Randomization of the union matrix. (C) Nested sort of the union matrix. (D) Modularity sort of the union matrix with a nested sort of each module.