2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/83424We show that very small-amplitude oscillations of a highly symmetric, spheric or cylindrical, interface (thin membrane) between two fluids can result in inhomogeneous instability and breaking of the interface symmetry: the frequency of the breathing vibration selects the spatial symmetry. This mechanism may govern morphogenesis.4 pages, RevTexFluid DynamicsBiological Physicstext