Mimosa pudica is famously called the sensitive plant because its leaves fold when touched.
This tropical legume reacts through a rapid movement called thigmonasty. Touch or vibration causes electrical and chemical signals to move through the plant, leading cells at the bases of leaflets and stalks to lose water pressure. The leaflets then fold and the whole leaf droops.
The response may discourage herbivores or startle small insects, although its exact evolutionary benefits can vary with conditions. The plant can reopen its leaves after a period of recovery. Repeated stimulation may also produce a weaker response, a phenomenon studied in plant behavior.
Mimosa pudica is not a carnivorous plant. Its movement is different from the snap-trap mechanism of the Venus flytrap, which closes specialized leaves around prey. Mimosa pudica is instead a flowering legume with pink, ball-shaped flower clusters.