Figure 3

Phase distributions. (a) Liquid phase in light grey, darker regions correspond to regions containing gas-liquid interfaces): (a) Images of liquid-gas phase distribution during drying in the stable system; (b) Images of liquid-gas patterns during drying in the unstable system: (b1) pinning of the evaporation front along the periphery of the outer row of cylinders, (b2) formation of an unstable gas finger and gas zone developing outward from the centre, (b3) collapse of evaporation front pinned on outermost pillars, (b4) last period characterized by the evaporation of liquid trapped within the system at the end of the preceding period; (c) liquid –gas phase distribution at different times during drying in the phyllotaxy-inspired system: (c1) evaporation –invasion front pinned onto the outer edge of spirals, (c2) invasion front within the device with chains of interconnected liquid bridges covering all the portions of spirals located in the region invaded by the gas phase, (c3) the tips of the chains of liquid bridges along the spiral have receded into the system. Movies of the three situations (a,b,c) are available online as Supplementary Information.