With each successive touch, the plant does more and more: two strokes causes the mouth to snap shut, while additional strokes indicate the size of the prey (bigger victims tends to twitch more) and causes the plant to produce a proportionally larger amount of "prey degrading hydrolases." Essentially, this ensures the plant only produces the amount of enzymes it needs on a per-meal basis, and prevents wasted production resulting from, say, a flower petal or some other non-food item grazing its maw. More than that, the production of a sodium channel that the plant uses to absorb said nutrient from its food gradually increases during this process as well.

It's a complex response that goes pretty deep into the plant -- not just a reflexive one. You could even call it smart. Cool. Now, if you'll excuse me, I think I'm going try adding a Venus flytrap to my current menagerie of houseplants.

[Image credit: Auscape via Getty Images]