The carnivorous plant regulates its feeding behaviour depending on how many times its trigger hairs are stimulated

This article is more than 4 years old

This article is more than 4 years old

Venus flytraps can count, according to scientists who tested the carnivorous plants and found they use their mathematical skill to conserve energy and avoid false alarms.

Researchers in Germany learned that the Venus flytrap adjusts its feeding behaviour according to the number of times the sensitive trigger hairs on its special leaves that resemble spring traps are stimulated.

“The carnivorous plant Dionaea muscipula, also known as Venus flytrap, can count how often it has been touched by an insect visiting its capture organ in order to trap and consume the animal prey,” said lead scientist Prof Rainer Hedrich, from the University of Wurzburg.

Hedrich’s team fooled the plants into thinking an insect had landed on it by applying increasing numbers of artificial “touches” to their trap hairs.

They showed that a single touch to a trigger hair was enough to prime a trap, setting it in “ready” mode but without snapping shut. A second touch caused the trap to close around the prey.

More touches stimulated the plant further so that after five triggers it started to produce digestive enzymes and molecules that take up nutrients.

Hedrich said: “The number of action potentials informs the plant about the size and nutrient content of the struggling prey. This allows the Venus flytrap to balance the cost and benefit of hunting.”

The findings are reported in the journal Current Biology.