If you look closely at the inner pink lobes of the Venus flytrap’s (Dionaea muscipula) trap, you will see several hairs. The trap shuts when an insect touches two or more of these hairs – or the same hair more than once – within a 30-second window. Tripping the hairs triggers an electrical impulse that propagates through the carnivorous plant’s modified leaves, opening pores in cells walls so that water rushes in and snaps the trap shut. Scientists can also force the trap to close by applying an electric current to its lobes.
Watch a video on the Venus flytrap and another carnivorous plant, the marsh pitcher, below:
[Excerpted from Scientific American]