Caption: 
Time-lapse fluorescence microscopy movie of oscillating droplets, showing that smaller droplets have larger variability in the frequency of their oscillations. By the end of the roughly 17-hour duration of the experiment, the chemical energy sources driving the oscillations have been depleted, and the reaction settles down. (Motions of the droplets midway through the movie are due to spurious fluid flow in the microscopy set-up, and are not relevant to the phenomena being studied.)