Fig. 6: Friction-induced transition in the wrinkling mode.

Snapshots and stress distributions are shown for two cases: (a–c) high friction (\({D}_{{\rm{b}}}^{\mathrm{on}}=36\,{\rm{n}}{{\rm{m}}}^{2}\,{{\rm{h}}}^{-1}\)) and (d–f) lower friction (\({D}_{{\rm{b}}}^{\mathrm{on}}=180\,{\rm{n}}{{\rm{m}}}^{2}\,{{\rm{h}}}^{-1}\)). Panels (a) and (d) show the biofilm surface morphology soon after the initial wrinkles form, while (b) and (e), and (c) and (f) display the corresponding stress and strain distributions, respectively. All results shown in this figure correspond to simulations where \({\rm{\gamma }}=9.2\,{\rm{\mu }}{\rm{J}}\,{{\rm{m}}}^{-2}\) and \({C}_{0}=1\,\mathrm{pg}\,{\rm{\mu }}{{\rm{m}}}^{-2}\).