Curious by Nature
Small discoveries from the wonderfully strange natural world.
Curious by Nature is a growing collection of brief notes on plants, fungi, ecology, biodiversity, and the quiet mechanisms that make the natural world so remarkable. One new curiosity is added at a time.
September 2026 · Carnivorous plants
Why Venus flytraps count to two
A Venus flytrap usually does not snap shut after the first touch of one of its trigger hairs. That touch generates an electrical signal called an action potential and leaves the trap temporarily primed. If a second action potential arrives within roughly 15–20 seconds, the trap crosses the threshold for rapid closure.
That short-lived “memory” helps the plant avoid wasting energy on raindrops, debris, or a single accidental disturbance. And the counting does not stop at capture: additional signals from struggling prey help activate the hormonal and digestive processes that turn a closed trap into a functioning digestive chamber.
There is a wrinkle, though. Experiments show that under some conditions one sufficiently strong mechanical stimulus can generate two action potentials, so the elegant rule is really about electrical signals—not simply two literal touches.
Research: Böhm et al., Current Biology (2016) · Scherzer et al. (2020)