There are many people who talk to their plants. What no one could suspect is that they can do it too, and at a volume similar to that of our voice. This has just been demonstrated, for the first time, by a team of researchers from Tel Aviv University, who managed not only to record the 'voice' of various kinds of plants, but also to analyze the meaning of the sounds they emitted. In a pioneering study just published by the journal 'Cell', researchers explain that the sounds, similar to a 'click', resemble the popping of popcorn and are emitted at a volume similar to that of human speech. We cannot hear them because they are high-frequency sounds, beyond our hearing range, but they can be perceived by different types of animals. As the researchers write in their paper, "we found that plants generally make sounds when they are under stress, and that each plant and each type of stress is associated with a specific identifiable sound. Although imperceptible to the human ear, the sounds emitted by plants can probably be heard by various animals, such as bats, mice and insects. Related News standard No The daisy that offers fake sex to obtain pollen ABC Science The South African flower recreates the shape of a 'seductive' female fly with its petals to attract males «From previous studies we know that vibrometers register vibrations in plants - explains Lilach Hadany, director of the research. But do these vibrations become sound waves in the air, that is, sounds that can be heard from a distance? Our study addressed this question, which researchers have been debating for many years." Listening to the plants In the first stage of the study, Hadany and his colleagues placed the plants in a speaker box in a quiet, isolated basement, with no background noise. The ultrasonic microphones, which record sounds at frequencies of 20-250 kilohertz (the maximum frequency detected by an adult human is about 16 kilohertz), were set up at a distance of about 10 centimeters from each plant. The study focused mainly on tomato and tobacco plants, but wheat, corn, cactus and henbit (a species of nettle) were also recorded. As Hadany explains, "before placing the plants in the acoustic box we subjected them to various treatments: some of them had not been watered for five days, in others the stem had been cut and others had not been touched. Our intention was to test whether plants make sounds and whether these sounds are affected in any way by the condition of the plant. Our recordings indicated that the plants in our experiment emitted sounds at frequencies of 40-80 kilohertz. "Unstressed plants made, on average, less than one sound per hour, while stressed plants, both dehydrated and injured, made dozens of sounds every hour." And the plants spoke Once the recordings were made, they were analyzed using a series of specially developed machine learning (AI) algorithms. The algorithms learned to distinguish between different plants and different types of sounds, and were ultimately able to identify the plant and determine the type and level of stress from the recordings. Additionally, the algorithms were able to identify and classify plant sounds even when placed in an extremely noisy greenhouse. During their experiment, the researchers monitored the plants undergoing a dehydration process over time and found that the amount of sounds they emitted increased up to a certain peak, and then decreased. In the words of Hadany, “in this study we resolved a very old scientific controversy: we proved that plants make sounds! Our findings suggest that the world around us is full of plant sounds, and that those sounds contain information, for example, about water shortages or injuries. We assume that in nature the sounds emitted by plants are detected by nearby creatures, such as bats, rodents, various insects and possibly also other plants, which can listen to the high frequencies and obtain relevant information. We think humans could also use this information, with the right tools, so plants can tell growers when they need watering. Apparently, an idyllic flower field can be a pretty noisy place. It's just that we can't hear those sounds directly! MORE INFORMATION news No A matter of size: life on Earth prefers larger and smaller individuals news No And the neutrino fell into the trap In future studies, researchers will continue to explore a series of intriguing questions: What is the mechanism behind plant sounds? How do insects detect and react to sounds made by plants? Can other plants also hear these sounds? According to Hadany, we are only at the beginning of a new era in the understanding of the plant world.
