  Carpets of actively bending cilia can exhibit self-organized metachronal
coordination. Past research proposed synchronization by hydrodynamic coupling,
but if such coupling is strong enough to overcome active phase noise had been
addressed only for pairs of cilia. Using a multi-scale model calibrated by
experimental cilia beat patterns, we find local multi-stability of wave modes.
Yet, a single mode, corresponding to a dexioplectic wave, has predominant
basin-of-attraction. Beyond a characteristic noise strength, we observe an
abrupt loss of global synchronization even in finite systems.
