Plant arithmetic

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.

[3][4] The mechanism is so highly specialized that it can distinguish between living prey and non-prey stimuli, such as falling raindrops;[6] two trigger hairs must be touched in succession within 20 seconds of each other or one hair touched twice in rapid succession,[6] whereupon the lobes of the trap will snap shut, typically in about one-tenth of a second.

[3] If a creature is too small, then the Venus flytrap has the ability to release it, which means that it can start the stage of becoming semi-open.

[3][4] The transition from closed to open will take two days and can result after the plant has finished digesting or realizing it has not caught anything worthwhile.

However, if the onset of darkness is unusually early, Arabidopsis thaliana reduces its use of starch by an amount that effectively requires division.