You’ve probably seen pitcher plants around. After all, they are a common sight in nurseries and at pasar malam markets. They are well known for being carnivorous, trapping small insects inside fluid-filled jugs where they unfortunately meet their sorry end. But what exactly are pitcher plants and why are they so different from normal plants?
The term “pitcher plant” generally refers to any carnivorous plant with pitchers that trap insects. This includes several families of organisms such as Nepenthaceae and Sarraceniaceae .
So, how do these plants catch their prey? Basically, insects make a beeline for the pitchers, attracted by their colour or the smell they emit. However, when they stand on the peristome, also known as the edge of the pitcher, they fall in, landing in a pool of enzyme-containing fluids where they are slowly broken down into simpler nutrients such as amino acids  .
Pitcher fluid contains more than just insect-digesting enzymes. In fact, the components that make up the fluid of different types of pitcher plants vary. While generally acidic, the fluid in certain species are mostly made up of rainwater that collects in the pitcher, while those in other species contain more secretions from the plant itself. Pitchers also have an operculum, or lid. In some species, the operculum prevents rainwater from entering the pitcher diluting its fluids.
Pitcher plants generally live in areas where the soil does not have enough nutrients for typical plants to thrive. Therefore, they rely on insects to obtain sufficient amounts of what they are unable to get from the ground. However, pitcher plants still photosynthesise to produce glucose. Insects are only a replacement for substances they would otherwise have absorbed from the soil.
It is interesting to note that many species of pitcher plants are not closely related to one another, suggesting convergent evolution – different organisms independently evolved to have this particular appearance and insect-trapping ability. For example, the Australian pitcher plant is more closely related to starfruit than to other species of pitchers . It’s pretty amazing how all these different pitcher plants adapted to their situation in similar ways.
So the next time you see one of these protein-guzzling plants around, do remember that they’re simply doing what they can to live their life to the fullest, just like you and me.