If you are imagining a monstrous plant, capable of swallowing a person, as in the cartoons, put it out of your mind: that kind of thing, dear reader, does not exist. The largest known carnivores are the creepers of the Nephentes rajah species, which rarely reach half a meter in height and tend to devour only flies. They are typical of the humid forests of the island of Borneo, in Asia, and they feed through a pitcher hanging from the end of their leaves. But not all carnivorous plants attack in the same way. The method of capture varies from species to species – some suck, others trap, bite or drown their victims. Certain carnivores are very greedy: the Drosophyllum lusitanicum, for example, manage to stick several insects to their fur at once. Those of the genus Utricularia devour, in a single suck, an entire family of microcrustaceans. Also worthy of mention is Dionaea muscipula, also known as the “flycatcher”: it snatches up distracted insects in just three tenths of a second, a record. But don’t think that carnivorous plants dispense with a more caloric menu. “From time to time, frogs and small birds become a side dish – not because they are attracted to the plant, but because, when they go after insects, they fall and end up devoured too”, says biologist José Maurício Piliackas, from Universidade São Judas Tadeu , in Sao Paulo. At lunchtime, every strategy is valid: as carnivores live in soils that are generally poor in nutrients, they cannot afford to do without food.
1. The provocative color and odor of carnivorous plants whet the appetite of insects, making them believe that they will find a feast of nectar there. The large size of Nephentes makes it even more succulent for the prey, which leaves towards the pitcher, the most showy part of the plant.
2. The innocent little fly lands on the plant to take a look inside. As the edges of the jar are smooth and covered by a moist and transparent substance, the insect slides straight into it, sliding along the inner walls until it falls into a reservoir of water.
3. Upon finding the liquid, the little animal floats and tries to survive, but ends up sinking and drowning at the base of the jug. This liquid is nothing more than rainwater boosted by substances released by the plant. Among these substances are proteolytic enzymes, which will initiate the insect’s digestion by breaking down its proteins.
4. To continue to digest the insect, the plant releases other proteins, such as lipase and protease. The process takes from two to five days, and at the end, the fly is reduced to a shapeless mass at the bottom of the jar, composed of the remains of the chitinous carapace.
green mousetrap
The leaf of Dionaea muscipula has two mouth-like shells, which are open waiting for lunch. The attack technique resembles the action of a mousetrap: when the insect lands on the hairs of the trap, the closing mechanism of the two shells is activated. The two parts of the leaf close, the victim is trapped inside and already begins to be digested.
Maximum pressure
Species of the genus Utricularia live underwater and use small pouches to capture food. At the entrance of these bags there is a small door connected to sensitive hairs, which work as triggers. When the prey touches one of these hairs, the little door opens and, thanks to the difference in pressure, everything around is sucked into the bag.
fatal superglue
Carnivorous plants like those of the genus Drosera have hairs that produce a sticky substance, which sticks the insects that land there. Some species even curl their hair around their prey to facilitate digestion. The more the bug struggles, the more glued it becomes, adhering to the sticky goo in which the digestive enzymes are already contained.