I have been always told as a child that, if you pluck the leaves, or harm the plant, they feel the pain and cry. So whenever I plucked flowers then onward, I used to look for their tears, with a heavy heart.
Let’s begin our search for – “DO PLANT HAVE FEELINGS?”
Early Research
The very first study about the same was done by Gustav Theodor Fechner, 1848. He was the one, cracking the non-linear relation between psychological sensations and physical intensity of a stimulus, given by S = K ln I.
Gustav Fechner claimed that, according to his study, plants, with a healthy environment of talk, affection and attention, have better and faster growth. In conclusion, they must feel the incoming good vibes.
This surely interested many upcoming researcher of that time.
One of them were Jagdish Chandra Bose (1900) and Grover Cleveland Backster Jr (1960).
Bose designed an experiment using crescographs. He devoted his time measuring plant responses to stimulus and analysed variations in their cell membrane potential as a response. Bose believed that an electric spasm occurs during the end life of plants and the actual moment of death can be accurately recorded. In short, his work showed that plants would feel pleasure and pain.
Backster followed him and used polygraph instruments, attached them to the plant leaves, helping him measure the electrical resistance changes whenever the plant was harmed or threatened to harm. The curious mind also built an experiment that consisted killing of brine shrimp in hot boiling water near the plants. Backster concluded plants do can feel pain and have the extrasensory perception (ESP).
Early research says, plants can perceive human intentions, human emotions and human thoughts.
Recent Research
1975, Horowitz, D.C Lewis and E.L Gasteiger re-attempted Backster’s experiment. They used an improved version of types of equipment for the experiment, completely isolated the plant to study, and removed every dust particle present for no disturbance in the result. To their surprise, they concluded no change in electrical resistance.
As per new experiments and investigation, the early positive results came because of defective instruments and were too spontaneous. Polygraphs may respond to static electricity and humidity changes. Further, plants do not possess sensory organs, which rule out the possibility of plants having ESP.
The television series named ‘Myth Busters’ (2006), addressed the experiments, mentioning that the early searches lack scientific protocols and were uncontrolled experiments with high error values and disproved the concept of plants having ‘feelings’.
Lets discuss more about it…
In 2019, a paper was published titled ‘Plants emit informative airborne sounds under stress’. According to the paper, plants emit high pitch ultrasonic sounds between 20-100 kilohertz, when harmed/threatened. These are unheard of by humans, hence they detected the sound emitted by ultrasonic microphones.
The debate begins again…
Pain is communication between stimuli, receptors, cells and CNS.
Therefore, plants emitting sound can be considered as basic stimuli, the same as the way plants react to the sun, gravity, soil and water. These responses are not intellectually processed emotions.
My thoughts
We are still learning and researching plants, and we have a long way to go. It is indeed difficult to boldly disclose – PLANTS HAVE NO FEELINGS.
Regarding experiments, there is no evidence of plants showing anything beyond mechanical stimuli.
Are plants living organisms?
Absolutely yes. But the absence of brain in plants limits their ability to take up stimuli, process it and give a conscious response.
Here comes the difference between mechanical response and conscious response.
Plants may respond to stress, but all the studies are in reference to unique responses to stimuli in specific species. The researches have a conspicuous absence of any response that is universal to plants, such as pain in animals.
There’s certainly more evidence backing up the thought that plants don’t have feelings.
The progress with scientific research will be very fascinating and maybe one day we can crack this question with confidence.
References:
- https://theminimalistvegan.com/do-plants-have-feelings/
- https://www.peta.org/features/do-plants-feel-pain/
- https://www.thebetterindia.com/76587/jagdish-chandra-bose-indian-biophysicist-radio-plant-physiology/#:~:text=Bose%20strongly%20believed%20that%20plants,in%20bromide%20(a%20poison)
- https://study.com/academy/lesson/the-backster-effect.html#:~:text=One%20man%20disagreed.,known%20as%20the%20Backster%20Effect
- Myth Buster 2006, Season 4, Episode 18
- Horowitz, K. A., Lewis, D. C, and Gasteiger, E. L. (1975).Plant Primary Perception: Electrophysiological Unresponsiveness to Brine Shrimp Killing. Science 189: 478-480.
About the author
Shruti Mandal, a sophomore of IISER Kolkata is ongoing her BS-MS course, in the department of biological sciences. She likes to introduce herself as a – ‘Jack of all trades, master of none ‘. She is a regular writer at The Qrius Rhino and you can find all her blogs here.