Carnivorous Plants: Insect Eating Plants
Albany Pitcher Plant
Weird Plants That Eat Meat
The idea of carnivorous plants is fascinating, causing images like those in the play The Little Shop of Horrors, where a plant grows so large and begins to protect the one person who cares for it... by eating people who hurt him. Okay, maybe that is a very sick idea of amusement, but hey millions watch the movie/play every year.
Fascination with carnivorous plants has been around for centuries. Those who used to practice witchcraft used to use the digestive enzymes for potions, exorcisms, and even medicines. Maybe the fascination with these plants is a result of the appearance of a backward food chain, where plants eat animals, instead of the other way around.
Albany Pitcher Plant
Five Bloodthirsty Ways a Plant Traps Its Prey
Although you won't see these plants chewing and gulping as Audrey II (the plant's name from Little Shop of Horrors) is seen doing, they do trap and digest meat in the form of small insects which land on them or fly near them. Most people, if asked what a carnivorous plant looks like, they would imagine a Venus Fly Trap. There are actually over 550 known kinds of carnivorous plants that find their nutrients in many ways. Some are active captures of their prey, while others will be passive and only capturing those who are unlucky enough to land on them. Aside from just active and passive meat-eaters, there are five specific ways a carnivorous plant can capture its food: pitfall, flypaper, vacuum, snap trap, and lobster pot traps.
Pitcher Plants Use a Pitfall Trap
Pitcher Plants are one type of meat-eating plants that use the process of pitfall traps to capture their prey. They are cylindrical and often have a flap above the plant. This flap overhangs the plant and prevents the insect from instantly flying out of it so that it has a better chance of landing and getting trapped.
Once a bug flies inside, if they choose to land on the interior wall of the plant, they will stick to a pool of bacteria known as digestive enzymes, similar to our own digestive enzymes. The pool of bacteria will not allow the bug to leave, and will instantly start breaking the insect down into nutrients that the plant will use to grow.
To the right, you can see how easily the insects fall victim to this kind of trap. Feel free to click on the plant, and look at all the little black specks. Those are all the different bugs that have found themselves inside these plants, which is a passive way the plant eats because the plant itself does not actively change its position when the bug lands.
There are many different types of pitcher plants that come in different shapes, patterns, and colors. You will see many photos of different types shown at the bottom of this article.
The flypaper trap is another very passive form of these meat-eating plants, or what Charles Darwin called Insectivorous Plants. They use, just as the name implies, a flypaper material to trap their prey. One example is on the plant you see to your right. By enlarging the picture, you will better notice there are little dots on the plant that appear to be either dirt on your screen on the plant itself. Those are tiny little bugs. These plants solely rely on their sticky leaves to trap and absorb insects. The bugs will usually land on them to eat themselves, and find that they are unable to move, which they then die. The plant then absorbs the nutrients from these bugs. The most recognizable of these flypaper trap plants are the Butterwort plant.
Venus Flytrap Plant
Now, if Audrey II had been a real plant, you would have found that she utilized a rapid leaf movement or snap trap, which, of course, would be one of the more active plant traps. Many of us are very familiar with the Venus Fly Trap, as it is one of the most well-known types of carnivorous plants. It is well known for being a bizarre-looking as well as the bizarre acting plant. When they are triggered, what appears as a jaw but really just two lobes, close in on its prey like a steel trap. By three hairs that are inside the "mouth," and when touched, trigger the trap. A Venus Fly Trap can only trap five times before the trap itself dies away, but the plant will continue to flourish!
To the right, you can see how similar the Venus Fly Trap looks like a real mouth, which is why it is the most notorious insectivorous plant. The ominous hair-like structures trap the insect inside, in which eventually the insect will land inside the trap. Once the bug lands, the trap will close and will remain closed until the contents of the insect have completely absorbed.
A Vacuum-like Bladder Trap
Another active plant is a bladderwort plant; this is different from the butterwort plant, which uses the flypaper trap. A bladderwort plant has a unique way of trapping bugs. It is usually a flowering type plant, and on its stem, there will be bladder-like enzymes, which are similar to the same enzymes found inside a pitcher plant. The difference is the bladder-like enzymes act as a vacuum to trap the prey. The bladder will have a tiny hole with a hinged door where an insect will be sucked into the internal parts of the plant. These kinds of plants often grow on waterlogged soil and lack roots. Because they don't get their primary source of nutrients deep within the soil, they need to get these from the bugs they ingest.
More Pitcher PlantsClick thumbnail to view full-size
Lobster Pot Trap
The final way a plant can trap insects is through a lobster pot trap. The lobster plant will have an opening that is very easy for a bug to enter. Still, it is nearly impossible to exit due to downward-pointing bristles that encourage the preys onward movement into the plant. Another belief is that these types of insectivorous plants act like Bladderworts because there is a vacuum type effect due to water movement within the plant. For this reason, it is sometimes classified as passive but also active. So imagine a horror story, where someone enters a cave, that they cannot escape. And though they feel like there is no opening on the other side, they keep going deeper into the cave in hopes of finding an exit. Well, in this case, the cave, or plant, literally eats the bug alive.
Meat-eating plants will forever capture people's imagination and curiosity. Someday, when I don't have plant-eating cats, I'm going to talk my husband into buying one for me. Until then, I will have to settle for a plant-free house, with an occasional visit to local gardens! Below you will see two fascinating books about carnivorous plants as well as a kit that I am so tempted to buy that allows you actually to grow a meat-eating plant. Due to my fascination, if you have any further information on these ominous looking plants, please share, I'd love to hear from you!
- Carlquist, Dr. Sherwin, et al. “Carnivorous Plants / Insectivorous Plants.” Botanical Society of America, 2005, www.botany.org/Carnivorous_Plants/.
- Michael Mathieson Senior Zoologist and Curator, Queensland Herbarium. "Death traps: how carnivorous plants catch their prey." The Conversation. February 07, 2018. Accessed February 26, 2018. http://theconversation.com/death-traps-how-carnivorous-plants-catch-their-prey-14811.
- "Pitcher plant." ScienceDaily. Accessed February 26, 2018. https://www.sciencedaily.com/terms/pitcher_plant.htm.
Questions & Answers
Do plants like Venus flytraps have venom to sting and kill the prey?
No, they do not have a stinger or venom. They rely on luring their prey inside their mouth where they close around the prey, and the pray cannot escape. It soon dies and is absorbed by the plant. Other insect eating plants rely on a very sticky interior that the bugs are unable to escape from.Helpful 3
What is a sundew?
This is a carnivorous plant I did not cover in the article. They are very uniquely shaped, with what looks like tentacles. They trap their prey through a sticky substance on the outside. Once the insect is stuck to them, the bug will eventually die, in which case the plant then absorbs the nutrients from the insect, essentially eating it. In other words, they are most similar to the flypaper trap.
© 2010 Angela Michelle Schultz