Yummy Bugs

We all have to eat. Turns out that some plants do too. Stuck in place through their root systems, plants depend on photosynthesis and essential nutrients they draw from the soil. When situated in soils that don’t supply sufficient nutrition for survival some plants evolve to simply supplement their diets. They turn into carnivores!


Venus Flytrap ready to pounce on a fruit fly (at bottom of photo). Photo Elizabeth Zusev

Carnivory, an efficient adaptation, involves many strategies. The various methods plants have figured out include pitfall, adhesive, snap, snare and suction. All methods end up with the prey in the plant version of a stomach where attendant digestive enzymes dissolve it into a soup. Perhaps best known is the Venus Flytrap, native to wetlands of the east coast. The snare trap, disguised with aromatic chemicals, captures its prey that is then herded down into the digestive bladder. It can be grown locally as can many other varieties of the more than 600 carnivorous plants eke out a living in nutrient poor habitats—bogs, swamps, forests, sandy and rocky sites. They have the know how to seduce, trap, consume and digest their favored prey including insects, reptiles, small mammals and even fish. They grow everywhere with the exception of Antarctica. And they come small and large. In Borneo the giant montane pitcher plant, Nepenthes rajah, the largest carnivorous plant in the world, has traps up 15 inches tall.

The first order for a carnivorous plant is to attract possible victims. Some offer a swell smelling nectar. Others color their lethal leaves to look like flowers. Some slyly camouflage themselves in other ways. Next: the ensnarement. The pitfall or pitcher uses pitcher shape leaves. The leaf’s rim  is laden with enticing nectar. It is also coated with a slippery substance that sends the prey sliding into the plant’s base where digestive fluids take over. Our native parrot pitcher plants (Sarracenia psittacina) grow tubular leaves that lay flat along the ground, adding a version of the snare. What appears to be a safe hideaway is actually a chemical bait to lure the prey. Once secured, the plant’s hairs force the victim into its digestive tract.The adhesive trap’s trick is to use sticky droplets that appear to be nectar.  As the victim struggles to free itself from the gluey slime it only becomes more submerged. Some take no chances of losing a victim by curling sticky tentacles around it.  Snap trap have trigger hairs that are activated when the prey enters the “flower.”  Alerted, they send an electrophysiological impulse to the leaf blades that snap shut. Suction traps mimic food or shelter. A trapdoor opens into a hollow bladder, creating suction that flushes the prey inside. The plants adaptions are one answer to Darwinian survival. For information: carnivorousplantresource.com.