Buzz
Plants may appear graceful and delicate, seemingly still compared to the rapid movement of animals. Their actions unfold so slowly that it’s hard to picture them as sinister hunters. However, nature is ruthless, and in the plant world, danger lurks in every thorn and leaf. Discover 10 clever ways plants ensnare and eliminate their foes.
10. Vacuum Traps
Stagnant water is often nutrient-poor. To compensate for this, the bladderwort has developed a unique technique for capturing water fleas as food.
Small leaves transform into hollow spheres with a door at one end. Water is expelled from the interior of these bladders, creating a pressure differential. Adjacent to the door are hairs that respond to pressure changes.
The plant then begins a patient waiting game, something it excels at. The moment a water flea brushes against one of the sensitive hairs, the door to the bladder swings open.
In less than a millisecond, the bladder rapidly inhales water—and with it, the unfortunate water flea. Inside, digestive enzymes break down the still-living flea. After digestion, the trap resets, ready for its next victim.
9. Strangling
In dense jungles and forests, real estate is scarce. Gaining ground space isn’t enough. Since plants rely on sunlight, they must compete for prime spots in the canopy. Some plants have adapted to live on other trees, elevating themselves into the canopy to access more light.
Strangler figs are not content being mere visitors. When a bird drops a strangler fig seed onto a tree branch, the seedling that sprouts begins sending roots all the way down to the ground.
Once the strangler fig reaches the soil, it begins to grow quickly. Its roots travel down the host tree’s outer surface, binding it securely. The fig then sends out branches and leaves that block its host from sunlight. Suffocated, the host perishes, and the fig claims the prime spot.
8. Drowning
Pitcher plants have adapted to survive in their nutrient-deficient habitats in a way that poses a threat not only to insects but also to small mammals and reptiles. Pitcher plants drown their prey.
The plant’s leaves are highly modified into pitchers that capture rainwater. The water becomes infused with chemicals that aid in dissolving whatever falls into it. The inner surface of the pitchers is so slippery that nothing can maintain a grip.
Once trapped, the animal has no escape. It drowns, succumbs, and is broken down to nourish the plant. The sight of a dead creature may even attract more animals, who could fall in and start the cycle anew.
7. Hair-Trigger Springs
Venus flytraps are perhaps the most iconic of all carnivorous plants. Many children receive them as both fascinating and frightening gifts. In their natural habitat, however, the Venus flytrap is considered endangered and can only be found in the wetlands of North and South Carolina.
In their nutrient-poor wetland environment, these plants have developed an elaborate mechanism to capture insects and spiders. The tips of their leaves transform into a set of jaws lined with spikes, and inside the trap are sensitive hairs.
When an insect ventures over the trap, it activates the hairs. To prevent accidental closure, the trap only springs shut if two separate hairs are triggered within 20 seconds. Once activated, the jaws slam shut around its prey.
The insect struggles to free itself, triggering additional hairs and ensuring the trap remains tightly shut. Once sealed, the trap engulfs the prey and begins digestion, eventually opening to reveal only the indigestible remnants of the insect.
6. Grasping Tentacles
Sundews adopt a more laid-back method of capturing insects for sustenance. These plants have developed mucilaginous glands scattered across their leaves, which produce sticky blobs of mucus. This mucus is rich in sugars, drawing insects to the plant.
However, once an insect lands, it becomes trapped. As it struggles to free itself from one tentacle, it accidentally contacts others, further ensnaring itself.
As if that weren’t enough, the tentacles are also capable of movement. They shift toward the insect, enveloping it completely. In some species, the entire leaf wraps around the trapped prey to guarantee it cannot escape. The same sweet mucus that attracted the insect also contains digestive enzymes to break it down.
5. Acid
In the United States, one of the most invasive wetland species is the common reed, Phragmites australis. It has taken over vast swathes of wetlands, becoming the dominant plant.
Many plants are known to release harmful chemicals to prevent nearby plants from encroaching on their space. This chemical warfare between plants is referred to as allelopathy.
The common reed is even more aggressive. Its roots excrete a potent acid that dissolves the root systems of neighboring plants. As these plants break down, they collapse and decay, providing the reed with the space it needs to expand and fight new rivals.
4. Flypaper
Butterworts are the laid-back members of the carnivorous plant family. Unlike the sundews, butterworts don’t rely on rapid movements to catch their prey. They simply position their leaves and wait for insects to land.
Their flat, sticky leaves secrete a mucus that insects may mistake for water or nectar. Once an insect gets stuck, its movements cause the leaf to gradually curl around it, fully enveloping the prey in digestive mucus.
Once the insect is broken down, the nutrient-rich fluid is absorbed by the leaf. Since the leaves used as traps wear out, the plant continuously produces new ones to optimize its chances of capturing its next meal.
3. Pain
Not all plants actively seek to kill. Some use sharp, stinging sensations to deter herbivores from munching on them. Typically, the pain is mild, and animals quickly learn to avoid them.
However, one plant has developed such an excruciating defense that it has even driven humans to suicide. The gympie gympie, native to Australia and Indonesia, has heart-shaped leaves covered in poison-laden needles. A simple brush against the leaf injects these needles into the skin, releasing a neurotoxin into the body.
The pain can be fatal to dogs, horses, and drive men to madness. One forester who mistakenly used a leaf of the gympie gympie as toilet paper is said to have taken his own life. The agony can last for years, and typical painkillers offer little relief from the torment.
2. False Exits
The California pitcher plant takes its trapping tactics a step further than most other pitcher plants. It doesn’t just rely on the usual methods to keep its prey inside its digestive liquid—it uses clever deception.
Rather than filling its pitcher with rainwater, this plant controls the water level by pumping it in. This is necessary because the entrance to the pitcher is curved, allowing insects to crawl in. However, once they’re inside, the plant cleverly conceals the exit, ensuring they can’t escape.
Not only does it hide the true exit, but the body of the pitcher plant also has translucent spots—false exits. Trapped insects, thinking they have found a way out, crowd around these misleading openings, never realizing the real escape is hidden. Exhausted by their futile efforts, they slip further into the pitcher to meet their end.
1. Lobster Pots
Technically, the tropical plant Genlisea doesn't have roots. If you were to dig one up, you'd find long white structures resembling roots. However, these are actually modified leaf traps designed to catch prey.
In place of roots, these traps function similarly to lobster pots, allowing creatures to enter but making it impossible for them to escape. The Y-shaped traps, with openings just 400 micrometers (0.02 in) wide, are lined with tiny inward-pointing hairs.
Any movement by an organism that enters the trap will cause it to drift toward the digestion area, where it will eventually be broken down. The prey of Genlisea consists of protists—minute, mostly single-celled organisms that navigate through the soil.
