Science
Flesh-Eating Plants: What Has Carnivorous Chlorophyll Ever Done For Us?
A natural history of carnivorous plants, their supernatural villainy, and the dangers facing these vengeful vegetables today
Flesh-eating plants: are they real? Where did they come from? And what can carnivorous chlorophyll tell us about how we view the murky, cannibalistic forests in our own backyard — and beyond?
Should we fear flesh-eating plants?
Should they fear us?
What has carnivorous chlorophyll ever done for us?
How do real carnivorous plants work?
Carnivorous plants grow in poor, boggy soils. They lack nitrogen and phosphorous, so they must get these nutrients from additional fertilizer.¹
In most cases, this means bug carcasses. In other cases, this means dining on guano or even small amphibians. They develop traps and triggers as a means to get these extra nutrients. Some carnivorous plants are more active than others.¹
Active, sticky, or a tall glass of water
Active carnivorous plants include the popular Venus flytrap, which despite its name mostly snares crawling insects. When two hairs of the Venus flytrap are triggered in succession, an electrical impulse closes the trap and sedates the creepy crawlies with a chemical plumbagin sedative. Lesser-known active and aquatic carnivores include the waterwheel plant and bladderwort.¹
Sticky carnivorous plants include sundews, butterworts, rainbow plants and dewy pines, and even tiny Philcoxia species that trap microscopic nematodes.¹
There are over 150 different types of pitcher plants ranging from the tropics to Australia and North America. But these all have one thing in common: they trap their prey using a sweet-smelling fragrance that gives way to a long shaft and pool of digestive enzymes, bacteria, and rainwater. This chemical cocktail breaks down unlucky travelers. Unless you’re a resident frog in one of these pitchers, that is.¹
One of the most famous pitcher plants Nepenthes lowii grows in Borneo. Tree shrews use this plant as a toilet!
Can they eat humans?
It’s important to note that while some of these carnivorous plants are being used as portable ponds and toilets, many can’t handle much larger prey.
“Chowing down on a vertebrate is incredibly dangerous for the plant,” says Barry Rice, conservation director for the International Carnivorous Plant Society. A carnivorous plant’s digestive enzymes might not break down larger meals before it rots, taking the plant down with it.
So as we explore the idea of flesh-eating plants, we dive into the weird and fantastical. We dive into the realm of Victorian gothic literature and science fiction. We dive into imperialist notions and forged travelogues, a Little Shop of Horrors, and Super Mario Bros.
Now, on to the human-munching bits.
A brief history of carnivorous chlorophyll
Early Victorian gothic literature and flesh-eating plants
Early Victorian literature was already dealing with eco-gothic themes, which question humanity’s relationship to our environment and explore “images of the apocalyptic, catastrophic, and the wilderness.” ²
Frankenstein is one well-known early 19th Century work that can be read through an eco-gothic lens. The looming forests and ice frame “a book about the usurpation of nature, as a being is brought to life from dead body parts thanks to industry and technology, which were radically altering the environment of Europe in the 1800s.”
Carnivorous plants, popularized by Charles Darwin’s Insectivorous Plants (1875), similarly upend the natural order in that they betray our anxieties about under-studied forests. They uncover “a dark, unwelcome and potentially dangerous environment — one which opposes conceptions of a sustaining, idyllic ‘mother nature.’” ²
They betray eco-phobia and the idea that imperialism might not always lead to a welcome discovery.²
One example of an early Victorian carnivorous plant is the Javanese upas tree reprinted in The Upas Tree of Fact and Fiction (1857). It stands decorated with a skirt of carnage picked clean and “about fifteen miles around the spot, the ground is covered with the skeletons of birds, beasts, and human beings.” While ominous, this fictitious killer is fairly easy to avoid if you heed the signs leading up to its vast graveyard.²
Later examples like the Madagascar man-eating tree are much more active and far more insidious.
Fictional flesh-eating vegetables
From late Victorian travelogues to Super Mario Bros, carnivorous plants have been slowly creeping out of the jungle into our daily routines. They come from unexplored frontiers and evolve as science fiction seeps onstage and into animated multiplayer games.
Madagascar man-eating tree
In 1878 an account of the Mkodo tribe described a tree demanding tribute in Madagascar. “The atrocious cannibal tree, that had been so inert and dead, came to sudden savage life. The slender delicate palpi, with the fury of starved serpents, quivered a moment over [the tribute’s] head, then as if instinct with demoniac intelligence fastened upon her in sudden coils round… her neck and arms… ever tightening with cruel swiftness.” Unsurprisingly, no such tree or tribe exists.³ Someone along the line failed to check their sources.
Similar to stories of the Nicaraguan vampire vine and the Javanese upas tree, there is a lot to unpack here. The tale of the Madagascar man-eating tree is awash with racism and assumptions that unfamiliar, unexplored, and ‘untamed’ wilderness is cannibalistic. What happens, then, when these carnivorous creatures show up in your own backyard?
Terrible Triffids
John Wyndham’s genre-forming 1951 pulp fiction novel The Day of the Triffids was one of the first stories that linked flesh-eating plants with scientific experimentation (and movie adaptations linked these carnivores with alien invasion.)
While Triffids remain popular and even inspired a 2022 Texas art exhibit, there’s little reason to turn to space for flesh-eating plants. Despite the (grossly incorrect) idea that mot of Earth has been “discovered,” much of Earth’s land surface isn’t even mapped, let alone explored and explained.
Researchers are still learning about habitats in the Amazon rainforest, marine predators in Antarctica, and even new species of bugs found in a busy city like Los Angeles. And this time, many researchers are working with indigenous groups and questioning whether they are “discovering” anything new at all.
Perhaps they are merely uncovering what has already been known for a very, very long time.
Audrey II
Little Shop of Horrors (1986) contributes to the “cannibal plant” trope in that the villain Audrey II is once again a “mean green mother from outer space,” and a larger-than-life monster that cannot be killed by a single bullet.
Unlike many of the carnivorous plants mentioned previously, Audrey II is constantly evolving. The New York Post describes how the puppeteers of the revived off-Broadway musical heightened their performance with every passing night.
“We kept trying to find fun ways to eat [the dentist’s] hand,” Eric Wright, one of two puppeteers that control the larger Audrey II, says. They began the show by bouncing the appendage around Audrey II’s mouth. Now, they try to spin that fake hand in the air until it finally disappears into the growing plant below.
Audrey II is well-adjusted to a world where art and science are continuously in flux.
A real-life Piranha Plant
The chomping Piranha Plant of the Super Mario Bros franchise has a real-life parasitic look-alike, Hydnora africana. Found in South African forests, this weed does not produce its own chlorophyll. Instead, it extracts nutrients from surrounding plants using its extensive root system.
While Hydnora isn’t technically a carnivorous plant, it does draw a large swarm of insects when in bloom. Its perfume smells like feces and attracts pollinators like hide beetles far and wide.
And a testament to the growing popularity of the Super Mario Bros Piranha Plant came in 2018 when Super Smash Bros Ultimate offered players the option to play as this vegetable villain (for an additional fee.)
Carnivorous plants are gaining popularity, both in the digital world and on aspiring botanists’ windowsills. Do we need to worry about this frenzy for insect-eating vegetables?
Carnivorous plants in danger
Real carnivorous plants are insidious hunters.* But for all their adaptations and botanical popularity, carnivorous plants around the world face many threats.
Loss of habitat is driving native North Carolinian Venus flytrap populations into the red, as is poaching. Venus flytraps rely on regular controlled burns, which thins competing vegetation. This type of controlled burn is becoming more and more difficult to manage in protected areas overgrown with competing vegetation. Venus flytraps also rely on low-lying boggy soils sensitive to sea level rise.
Poaching is a huge problem for carnivorous plants in the wild. In 2014 it became a felony in North Carolina for any person to “dig up, pull up, take, or aid in taking or carrying away a Venus flytrap plant, or the seed thereof, growing on the land of another person, or from the public domain, without a permit signed by the landowner.” This threatens poachers with jail time if they disrupt native North American Venus flytraps. But simple carelessness is another threat to these chlorophyll carnivores.
One viral video shows a group of women picking Cambodian Nepenthes mirabilis, an endangered and distinctly phallic Venus flytrap species for the camera. Cambodia’s ministry of the environment called out the video and expressed concern about how smartphone use might put further pressure on these rare plants.
Kindly leave carnivorous plants alone.
What has carnivorous chlorophyll ever done for us?
Eco-phobia is not a thing of the past. With climate change looming in the news cycle, it’s difficult not to draft media monsters and mother-earth villains that turn our assumed dominance over nature upside-down.
Carnivorous plants have never eaten man whole. Instead, they have offered us medicinal properties, an inspiring eco-gothic genre. They have given us reasons to protect native plant species in the US and everywhere carnivorous plants are threatened today.
And new research suggests that Venus flytraps “carefully calibrate” the number of enzymes needed to digest its dinner, which supports theories about plant cognition, the idea that plants process information related to their survival and make decisions in a process that looks a lot like behaviors previously observed only in animals.
So while flesh-eating plants might be off the table for the present, we have a lot to learn from carnivorous chlorophyll. Just be sure to check your eco-phobia before wandering into your friendly neighborhood bog.
Works Cited
[1] Torre, Dan. Carnivorous Plants. 1st ed., Reaktion Books, Limited, 2019.
[2] Price, Cheryl Blake. “Vegetable Monsters: Man-Eating Trees in Fin-De-Siècle Fiction.” Victorian Literature and Culture, vol. 41, no. 2, 2013, pp. 311–27, https://doi.org/10.1017/S1060150312000411.
[3] Nissan, Ephraim. “Deadly Flowers and Lethal Plants. A Theme in Folklore, Fiction and Metaphoric Imagery.” Fabula, vol. 50, no. 3–4, 2009, pp. 293–311, https://doi.org/10.1515/FABL.2009.024.
[4] Tagawa, Kazuki, and Mikio Watanabe. “Group Foraging in Carnivorous Plants: Carnivorous Plant Drosera Makinoi (Droseraceae) Is More Effective at Trapping Larger Prey in Large Groups.” Plant Species Biology, vol. 36, no. 1, 2021, pp. 114–18, https://doi.org/10.1111/1442-1984.12290.
Notes:
*Carnivorous plants are insidious hunters, and a recent study shows that they may have more success when hunting as a group.⁴
