Fig S.3.1: (A) Duplication of regulated gene. Multiple duplication events of regulated genes can explain the evolution of Single Input Modules (SIMs). (B) Duplication of transcription factor. Duplication of an autoregulatory transcription factor can explain the evolution of Feed-Forward motifs (FFs). (C) Duplication of transcription factor and regulated gene. Multiple duplication events can explain the evolution of Dense Overlapping Regulons (DORs).

E. coli
Information on Feed Forward (FF) motifs Clicking here will take you to a page which contains information on the FF motifs used in the present analysis	Information on single input modules (SIM) Clicking here will take you to a page which contains information on the SIMs used in the present analysis
Yeast
Information on Feed Forward (FF) motifs Clicking here will take you to a page which contains information on the FF motifs used in the present analysis	Information on single input modules (SIM) Clicking here will take you to a page which contains information on the SIMs used in the present analysis

Fig S.3.2: (A) Internal duplication in yeast SIMS. Blue circles represent transcription factors and yellow circles represent duplicated genes within each SIM.

Fig S.3.2: (B) Internal duplication in E. coli SIMS. Blue circles represent transcription factors and yellow circles represent duplicated genes within each SIM.

Fig S.3.2: (C) Internal duplication in yeast FFs. Coloured circles within each FF represents transcription factors that are duplicates.