The Venus flytrap (Dionaea muscipula) is a carnivorous plant that catches its prey—chiefly insects and arachnids—with a trapping structure formed by the terminal portion of each of the plant’s leaves, which is triggered by tiny hairs (called “trigger hairs” or “sensitive hairs”) on their inner surfaces.

When an insect or spider crawling along the leaves contacts a hair, the trap prepares to close, snapping shut only if another contact occurs within approximately twenty seconds of the first strike. Triggers may occur with a tenth of a second of contact. The requirement of redundant triggering in this mechanism serves as a safeguard against wasting energy by trapping objects with no nutritional value, and the plant will only begin digestion after five more stimuli to ensure it has caught a live bug worthy of consumption.