According to a study conducted by Tel Aviv University in Israel, and recently published via pre-print server bioRxiv, plants emit an ultrasonic scream when deprived of water or when their stems are cut, which isn’t audible to the human ear.
Researchers at the university placed a microphone 10 centimetres away from a set of tomato and tobacco plants, and recorded ultrasonic sounds between 20 and 100 kilohertz when the stems were cut or the plants were dehydrated. As is turns out, the tobacco plant screams louder when thirsty than it does when cut.
Now, this isn’t the first time we’ve been stunned by the abilities of plants. A recent study indicated that plants can ‘hear’ water and will grow their roots towards the water source in response. Another study also indicated that particular music can increase the growth rate and quality of your plant.
While the research found that the sounds emitted by plants are not heard by human ears, scientists hypothesise that organisms that are sensitive to ultrasonic frequencies – such as mice, bats and even other plants – may actually be able to hear the cry of a plant in distress from up to 4.5 metres away.
The study provides a whole new perspective to the sentience of plants.