Like the pitcher plants and the sundews, the “carnivorous” part of the venus flytrap is a modified leaf. Located on the inside of the leaves are sparsely spaced trigger hair. When an insect touches these hairs, an action potential is generated, signaling the leaf to close shut. What’s interesting is that the action potential can only be propagated after two hairs are touched. This prevents the plant from wasting energy on trapping inanimate objects with no nutritional value.