Venus Flytraps 'Count' Touches To Optimize Eating Bugs

Venus flytraps are creepy enough on their own — they're plants that bite down on whatever happens to wonder inside their 'mouth,' after all, digesting the poor unwitting creature. As it turns out, though, the plants are more complex than previously known, using a fairly sophisticated 'counting' method to determine the size of a bug and how much digestive juices it will take to eat it.

The effects of this 'counting' method are somewhat poetic — the more the bug struggles, the greater the quantity of digestive juices will be triggered, sealing the bug's fate. Five touches is the sweet spot — for the plant, that is — but bad news for the bug. A single touch won't trigger the plant to close, but will stimulate some sensory hairs, getting them close to their threshold.

When a second touch is registered, those sensory hairs are pushed past their limit and the 'mouth' snaps shut, trapping the bug in a little prison. The plant is waiting for more movements before it will proceed, however; if the bug were to hold still at this point, the plant would eventually open and set it free.

Of course, a surprised and trapped bug will start thrashing, and when it does the plant will be 'counting' how many times it is touched. Upon the second touch, the planet's jasmonic acid, a hormone, is released. The third touch, then, triggers the production of the actual digestive enzyme.

It isn't until the fifth touch, though, that plant also starts drawing in sodium through 'pumps' to liquify the meal. Every touch that happens after that point increases the amount of digest enzymes, speeding up the process. The thought process is that larger bugs will survive longer, being able to get more kicks in. The plant will then know that it has more to digest and will respond as needed, but will do so proportionally, avoiding wasting nutrients in the process.

The moral of the story? If humanity's future includes gigantic flytraps and you get snagged in one, stay very, very still.

VIA: New Scientists