Nature · 2
How many times must a Venus flytrap's trigger hairs be touched before the trap snaps shut?
Answer
Twice
A single touch to the trigger hairs primes the Venus flytrap but does not close it; a second touch within roughly 20 seconds is required to confirm prey is present and trigger the snap. This two-touch threshold prevents the plant from wasting energy closing on raindrops or wind-blown debris.
💡 Did you know?
Venus flytraps count prey touches: one triggers reflex, but trap only closes after two touches within 20 seconds—preventing false alarms.
Other options people guess
- Once
- Three times
- Four times
Topics
- venus-flytrap
- carnivorous-plants
- plant-biology
- adaptation
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