Quantification and functional analysis of modular protein evolution in a dense phylogenetic tree

► Modular evolution can create large diversity over evolutionarily small time-scales. ► We derive rates of arrangement gain/loss and quantify key events in modular evolution. ► The majority of novel arrangements can be formed by one of four mechanisms. ► A small number of novel arrangements harbor unusual patterns of “supra-repeats”. ► We explore possible functions preferentially associated with modular rearrangements.