Movie S1.

Time series of fluorescence micrographs of a PSM (DOPC/SM/chol/Gb3/Texas Red DHPE, 39.5:35:20:5:0.5) prepared on a pore with rpore = 2.75 μm. The movie [45 frames per second (fps)] shows the coalescence of two diffusing center lo domains; they condense to form a single, larger lo domain.