Category Archives: Plants

Pitcher Plants

“Wish I could use some of your stuff in my classes but it is too ‘mature’ in language.” –My mom, a middle school science teacher.

Mom, the articles are called Badass Biology. These ain’t no cupcake creampuff articles for babies. These are articles for ass-kickers that love facts. I want my articles to cause nosebleeds.

If my articles were plants, they’d be carnivorous. Only, they’d be sneaky and deceptive, luring in readers with the promise of sweet nectar but instead causing them to fall into an unescapable chamber and drown in a vat of literary acid. I wish nature was awesome enough to grant us a plant so wonderful. That would kick ass.


1) They f**king exist.

You know there’s going to be some serious s**t going down when the first item of a list tells you that something exists.

The plants I’m referring to are called acid death plants. I lied, they’re called  trap dissolvey plants. I lied, they’re called pits of agony plants. I lied, they’re called swimmey swwimmey death time plants. I lied, they’re called roses. I lied, they’re called pitcher plants. They encompass a broad and diverse array of plants from many ancestral lineages that contain one common feature: an unescapable pit of doom and death which the plants dissolve, digest, and absorb their unlucky prey. Pitcher plants also have googly eyes, which is pretty sweet.


Pitcher plants come from a variety of locales and lineages. However, all have independently evolved googly eyes.

The pitchers for which these plants are named are actually highly modified leaves, tempered into kick-ass death traps by the will to survive. Called pitfalls, these leaves have three primary zones, all of which are designed to trick insects into letting a plant kill and eat them. Bummer.

 Zone 1: The bait and slip.
The opening of pitfalls contains some kind of delicious bait that attracts insect prey. Baits can include cells that produce nectar, tiny hairs called trichomes that release sweet-smelling chemicals, or parking lots where local food trucks meet to entice flies and ants with Korean-Mexican fusion

But trouble awaits the hungry. When insects land to feast upon barbecued tacos, they land on a slick waxy surface that causes them to slip into the pitfall. Those plantey bastards. However, these waxy coatings are most efficacious when wet; some insects do not slip on this coating when the plant is dry. Even more bastardly is the strategy of Sarracenia flava; the opening is also coated with an insect anesthetic that paralyzes prey and reduces their chances of escape, made unlikely by the next zone…

Zone 2: There is no escape
The walls of the pitfall are structured in a way that makes escape essentially impossible for insects that are either too clumsy or too stupid to figure it out. The plants’ means of accomplishing this task depends on its taxa; some plants utilize downward-growing hairs that make the walls difficult for insects to climb. Others implement waxy scales or folds in the wall tissues. By far, the most interesting is that of some members of the genera Sarracenia (seriously, these guys kick ass) and Darlingtonia. The walls of their pitfalls are lined with tiny aldehyde crystals that hinder upward motion, turning the walls into a beautiful biological Aggro-Crag.

Zone 3: The pit of despair
It’s no surprise that liquid fills the bottom portion of pitcher plants. The main ingredient in this mixture is rainwater, collected by funneling into the pitcher using a series of specialized companion leaves. However, these leaves also act to repel water to prevent inactivation of the second ingredient in this deadly cocktail: rocket swords. I mean acidic digestive enzymes. These enzymes break down any poor prey that falls into the trap, leaching nutrients into the surrounding medium that can be absorbed by cells lining the pitfall. These enzymes are so powerful that they often hurt the plant itself. To counter this, some pitcher plants release additional compounds that form a physical barrier that prevents chemical damage to the inner wall. In other words, these plants are so deadly that they need to protect themselves from themselves, much like a tattoo of the Triforce from the Zelda games protects you from women.

Like a fisherman that like, I dunno, uses his eyes to look at his catch, pitcher plants can also sense how much food they’ve caught. To prevent excess damage to themselves, pitcher plants keep the amount of nasty enzymes low and release a lot more of them once they’ve caught food. Interestingly, the amount of enzyme they release is related to the size of the food item they’ve captured; larger prey causes more enzymes to be released. How do they know? Pfft, I don’t know, but I bet it’s complicated. I’m just going to claim nobody knows exactly how it’s done.

2) The pitchers arose in different groups of plants independently

I don’t know why people think evolution creates “perfect” organisms. That’s not the point, otherwise I’d be able to shoot laser beams from my eyes. Don’t worry, I’d use them for good, like scanning barcodes or calculating the dimensions of a bedroom. However, that’s not how natural selection works. Instead, organisms just need to be good enough to survive and reproduce. These changes are usually small ones, and they’re very infrequent. However, harsh environments can speed up the process by exerting a lot of pressure to adopt a particular adaptation in order to meet these needs.

Sometimes, different organisms adapt similar strategies to survive in their environments. Desert plants are a prime example of this; many have developed thorns, thick tissues, light color, cookie fruits, the ability to change color when frightened, and root systems that are broad or deep because those adaptations work in those tough environments. When different organisms developing similar adaptations, convergent evolution occurs.

That’s also exactly how pitchers developed over evolutionary time. Pitcher plants come from several different taxonomic groups that have all independently developed pitfalls. Not only that, but their pitfalls are strangely similar considering the plants’ diverse ancestry, which presents an added level of elegance to this whole thing.

Convergent evolution; All of these organisms have independently developed the tendency to be gigantic assholes to other species.

3) Their ecology is just so friggin cool

An organism’s ecology describes how it interacts with living and non-living things in its environment. Typically, an organism’s effects on other organisms are more direct and important, so that tends to be what most ecologists study.

Most of the interactions between organisms involve a negative component. Herbivory, predation, parasitism, and competition are all forms of interaction where one or both of the parties suffer for taking part. However, organisms can also help one another by facilitating each other’s growth or reproduction or by providing refuge against competitors or consumers. Interactions where both parties benefit are deemed mutualistic.

Pitcher plants, being the badass acid pits that they are, actually do a lot of good for their communities. Bacteria grow in the pitfalls in high densities, providing nutrients and additional digestive enzymes for the plant in exchange for a suitable place to live and multiply. Small insects, such as mosquito larvae and ants, use the plants as a shelter while helping to speed up digestion of prey. The VFW rents out pitcher plants for Wednesday night bingo tournaments. Weirdest of all, small mammals like rats, bats, and shrews use pitcher plants as toilets, providing much-needed nutrition for the plant while separating the animals from their waste.

What’s coolest is that pitcher plants harbor tiny aquatic communities. As time goes on, some species invade, others go extinct, and so on until the pitcher plant dies. Thus, pitcher plants can act as mini-environments, providing an easy way for ecologists to study how nearby communities can influence one another over time and how they vary across space.

4) I’m done.

5) No I’m not. 

I wanted to restate that these plants are probably some of the coolest non-moving things to have ever not moved. They’re the natural world’s equivalent of a pit of spikes, only they facilitate unique communities and foster the growth of nearby species. They’re like benevolent angels covered in cactus thorns that lie in wait for wicked-hearted brigands to seduce, only to consume their souls the very second they fall into the trap.

Much of the information in this post came from the paper accessible through the following link:

Krol, E, BJ Plachno, L Adamec, M Stolarz, H Dziubinska, and K Trebacz. 2012. Quite a few reasons for calling carnivores ‘the most wonderful plants in the world’. Annals of Botany 109: 47-64

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