The rapid closure of the Venus flytrap (Dionaea muscipula) leaf
in about 100 ms is one of the fastest movements in the plant
kingdom. This led Darwin to describe the plant as “one of the
most wonderful in the world”1
. The trap closure is initiated by
the mechanical stimulation of trigger hairs. Previous studies2–7
have focused on the biochemical response of the trigger hairs to
stimuli and quantified the propagation of action potentials in the
leaves. Here we complement these studies by considering the
post-stimulation mechanical aspects of Venus flytrap closure.
Using high-speed video imaging, non-invasive microscopy techniques and a simple theoretical model, we show that the fast
closure of the trap results from a snap-buckling instability, the
onset of which is controlled actively by the plant. Our study
identifies an ingenious solution to scaling up movements in non-muscular engines and provides a general framework for understanding nastic motion in plants.