Meat eating plants do exist, and most of them are insectivorous, which means they trap and ingest bugs through various mechanisms. Over time it appears these plants have evolved a digestive process, along with photosynthesis, in order to adequately resolve the plant’s nutritional needs. Meat eating plants are of several different types and are often grouped by the means through which they trap.
Pitcher plants create what are called pitfall traps. Most believe these plants to simply have evolved from plants with rolled leaves. Unsuspecting insects may enter the top of the leaves, often rolled or trumpet like in shape, and quickly fall to the bottom, where the plant secretes enzymes like protease and phosphotase. An insect at the bottom of the pitfall is trapped, and quickly becomes the victim of the meat eating plant.
One would think that all meat eating plants are tropical, like the Venus flytrap. However, there are actually some species of pitcher plants that use pitfalls in California and Florida. Even Canadians have found the Northern Pitcher growing in the wild.
Another common method of trapping insects employed by meat eating plants is secreting a sticky substance that renders the insect immobile. These are normally called flypaper traps. Many of the flypaper trap plants are from the Sundew family. An insect that lands on flypaper trap meat eating plants sets off chemicals that cause the plant to quickly grow and fold up to prevent the insect from escaping. Once the leaf has rolled, the captured insect is digested through enzyme secretion.
The Venus flytrap is a sundew, but employs a snap trap mechanism. Tiny hairs along the surface of these meat eating plants are set off when an insect lands on the plant, acting as an alarm. Once the “burglar alarm” is set off by a hapless insect, the flytrap quickly closes up and seals within a matter of seconds,
Less common trapping mechanisms include the bladder trap, which secretes water, forming a vacuum-like effect for insects. These are commonly found near water. The lobster pot meat eating plants are also quite rare. The plants can have a corkscrew shape like the Genlisea, which makes entering the plant easy, but exiting it quite confusing for the insect. Essentially the insect moves down the spirals until reaching a digesting area of the plant.
Much has been made fictionally of meat eating plants actually eating mammals, but most accounts, like that in the play Little Shop of Horrors are exaggeration. However, the occasional mammal has been the victim of the meat eating plant. This occurred in France in 2005 at a Botanical Garden in Lyons.
A pitfall trap plant was found to have a partially digested mouse inside. The plant was brought to the attention of botanists after people visiting the garden began to comment on the terrible smell emitting from the area where these plants from the Philippines were showcased. This discovery has led to more interest in whether some plants do rely on mammals, as well as insects, for food sources.