Plants let out secret high-pitch screams when stressed

 

Credit: Lorenzo Ranieri Tenti

Researchers at Tel Aviv University have discovered that plants emit ultrasonic sounds when stressed, comparable in volume to human conversation but too high-pitched for humans to hear. Using microphones, they recorded tomato and tobacco plants in both soundproof chambers and noisy greenhouses. When deprived of water or cut, plants produced 30–50 clicks or pops per hour, while unstressed plants emitted far fewer. A machine-learning algorithm successfully distinguished between sounds from thirsty, cut, or healthy plants, and even identified which plant produced them. The mechanism behind these noises is unclear, though scientists suspect bursting air bubbles inside plant tissues. While humans cannot hear them, insects and mammals likely can, suggesting plants may participate in acoustic communication with their environment. This could help animals decide where to feed or lay eggs, and even allow nearby plants to prepare for stress. The findings highlight hidden layers of plant interaction and resilience

Read more: Plants let out secret high-pitch screams when stressed - BBC Science Focus Magazine