Fig. 2

Stereoscopic pictures of the liquid film on the “bacterial trail” (a) and “bacterial bridge” (b) devices and the distribution of the liquid film widths on four independently printed devices of each type. The photograph in each panel shows a typical stereoscopic image of the liquid films on the corresponding device. For each of the four devices of each type, a total of nine measurements of the liquid film width were measured and overlaid with the corresponding box-whisker chart. The middle line in each chart shows the median of the data points; the upper and lower boundaries of the boxes mark the 25% and 75% quantiles of the data. The liquid film widths do not differ significantly within a device type