Recently, researchers in the Key Laboratory of Biomimetic Materials and Interface Science, Institute of Physical and Chemical Technology, Chinese Academy of Sciences have made new progress. Under the sudden and spontaneous suspension of bubbles, the liquid staying on the surface of the mouth edge of the Nepenthes mirabilis can move and crawl in a directional and rapid manner like an inchworm. Both depressurization, vacuum pumping, and chemical reactions can cause the sudden nucleation, growth, coalescence (Ostwald ripening process), and rupture of bubbles in asymmetric microcavities on the surface of the mouth edge of Nepenthes mirabilis, resulting in directional overpressure beneath the liquid, leading to directional contraction and expansion of the liquid. This new liquid directional movement mode regulated by bubbles is expected to be applied in microfluidic devices, oil-water separation, and water collection systems.

Figure S1. Scanning electron microscopy (SEM) images of the mouth edge surface of Nepenthes pitcher plants (Phenom Pro) (a), (e) Scanning electron microscopy images of the inner surface of the mouth edge at different growth cycles. (b) - (d) and (f) - (h), high magnification scanning electron microscopy images of the mouth edge surface of Nepenthes.