When you think of math, you might think of students sitting in desks, working diligently to complete math problem or a teacher standing up in front of a class teaching math. Outside of the classroom setting, you might also think of a nuclear physicist or accountant working out equations and testing them or sitting crunching numbers on a spreadsheet. What you might not think of when you think of math is a plant, sitting in a boggy, marshy area of South Carolina, waiting rather patiently and rather calmly and then… SNAP!...eating a fly who happens to land on one of the inside of its leaves. There is only one type of carnivorous plant like this that we’re aware of and it’s known as Dionaea muscipula, or the Venus Flytrap. Venus Flytraps were partially made famous by a musical called Little Shop of Horrors about a man-eating Venus Flytrap named Audrey, but did you know they also can do a little bit of math? Read on to figure out how these already unforgettable plants can also count.
To begin, Venus Flytraps aren’t always carnivorous. The plants depend on insects for food only when they live in soil that doesn’t have enough nutrients for them to be able to survive otherwise. Being deprived of what they need in soil makes them go into carnivorous mode, but closing their huge mouths takes a lot of energy. When an unsuspecting insect steps inside the plants jaws, which make a nice surface to land on for bugs, Venus Flytraps have to be very certain that the insect will stay there long enough for it to snap its mouth closed and catch it. And this is where the number two comes in. Venus Flytraps have tiny hairs on the leaves that form their terminal or mouth that are called trigger hairs. When the Venus Flytrap feels an insect brush against their trigger hairs twice, their mouth snaps shut in a fraction of a second. The snapping motion is done by electrical impulses called “action potentials” or APs. If Venus Flytraps feel two APs within 20 seconds, specifically, they think they’ve caught dinner.
Beyond the two action potentials that indicate for the Flytraps to snaps their mouth shut, there’s a third AP that works to figure out what kind of insect it’s caught and a fifth AP that starts digesting it. Movement of the insect is also important. If an insect stops moving after step #2 when the Flytrap shuts its mouth, the plants stops the rest of the steps and open its mouth again to have another shot at catching prey. If the insect moves and struggles to escape, the Flytrap knows it’s caught a live one and will continue with the rest of the steps to digest it. It’s generally a long, slow death for the insects that Flytraps eat, as studies have shown that the average insect still stimulates Flytraps 63 times after closing its mouth during digestion. After Venus Flytraps are done with their meal, they open up about 10 days later and nothing but a bug carcass remains. It would then pay to be a calm bug in that mouth, as you would be set free!
Like many plants, Venus Flytraps have flowers. They bloom above their stems and leaf mouths. Flytraps then rely on insects for pollination. So, insects who are attracted to their patterns, colors, smell and nectar collect pollen from the Flytrap flowers and distribute it to other Flytrap flowers. Some of the main insects that pollinate them are long-horned beetles, checkered beetles and sweat bees and what’s fascinating about this is that Venus Flytraps do not trap their pollinators – they know the difference between prey and their pollinators. But how? Scientists aren’t entirely sure, but they speculate that the pollinators might be able to distinguish color. The color of the trap parts of a Venus Flytraps generally varies from red to different shades of green, and the flowers are always white. They also believe that their pollinators understand where to land and not to land. There are about six inches between the white flowers and the deadly traps below on Venus Flytraps, making the ability to navigate position an important one. A very symbiotic relationship, indeed.
With all this talk about the savageness of Venus Flytraps, you might be wondering what happens when they don’t catch anything? Surprisingly, Flytraps can go a long time without eating bugs, even in poor soil. Months, for certain… that is, unless they are falsely triggered too much. When the plants close their mouths on something that isn’t prey, they are expending so much energy. If the plant does this more than a couple times without catching something in between, it will die. Generally, thanks to counting Venus Flytraps can save their energy for when they really need it to eat! Math is really important to these plants and their killer jaws.
