Can plants really talk?

Leviathan Press:

When we say "plants can talk", we may have fallen into a misunderstanding: behind talking is the intention of communication, implying that being able to talk represents a certain intellectual activity that we recognize. But the actual situation may not be what we imagine. To paraphrase Wittgenstein's famous saying, "If lions could talk, we would not understand them." Lions, like plants, are life forms that are very different from us. Language only serves (and in turn shapes) the actual needs of the life form that produces them. This is equivalent to excluding the impulse to anthropomorphize plants.

Laura Beloff's plants seem to click. She connected the plant's roots to a contact microphone that detects faint high-pitched sounds in the soil. Using a software program she wrote, the sounds are lowered in frequency so that they can be heard.

Artist and associate professor at Aalto University in Finland, Belov was working at her desk when she heard a joyful clicking sound from the plant installation next to her. That's when the strangest thing happened, Belov said. Someone came to her room and the clicking stopped. When the person left, the sound started again. Later, more people came to visit her and the sound stopped again. Only when the person left did the sound start again. "I still don't know what happened," Belov said.

Laura Belloff with her plants. © Bioart Society

It was as if the plant just wanted to talk to Belof privately, and it kept speaking to her.

Belov has been studying the sounds plants make, on and off, for more than two years. She’s still not sure what’s going on. She doesn’t have expensive equipment, just a simple microphone that she thinks can pick up microbial sounds from the soil or other sources—not necessarily plant sounds. The idea that plants are communicating or reacting to people entering the room is just an inference.

(direct.mit.edu/lmj/article/doi/10.1162/lmj_a_01097/97062/The-Hearing-Test-Evidence-of-a-Vegetal-Entity)

But the possibility, the tiny probability, fascinated Belov. “Is it really so? That’s the question,” she said.

There is still a lot we don’t know about plants and their lives. Right now, plant researchers are debating the extent to which flowers and shrubs can communicate with each other and other organisms. If they can, does that mean they have intelligence?

Some plants do seem to respond to vibrations, chemical signals and sounds, but the idea that they can "communicate" remains controversial. © Elva Etienne/Getty Images

Scientific research continues to bring new discoveries, showing the complexity and surprising abilities of plants. Plants may be more complex than some people think. However, the idea that they can "talk" to humans remains controversial.

Despite this, some people still try to talk to plants. They are plant interlocutors.

Beloff got the idea to listen to plant roots after learning about experiments by Monica Gagliano of the University of Western Australia and other researchers. Over the past decade, Gagliano has published a series of papers showing that plants can communicate, learn and remember.

She has long called on scientists to pay more attention to the fact that plants can transmit and obtain information through sound. In a 2017 study, Gagliano and her colleagues demonstrated that plants can sense the vibrations of water sound through their roots, which may help them locate groundwater.

(academic.oup.com/beheco/article/24/4/789/218916?login=true) (link.springer.com/article/10.1007/s00442-017-3862-z)

Galliano is convinced that plants can communicate. The evidence, she says, is overwhelming.

In a widely cited 2012 paper, she and her colleagues reported on detecting the clicking sounds of plant roots. The researchers used laser vibrometers to detect the sounds at the root tips. The devices were submerged in water and placed at the base of the plant in a laboratory setting, which ensured that the sounds were indeed coming from the roots, Gagliano said.

(www.sciencedirect.com/science/article/abs/pii/S1360138512000544)

While more evidence is needed to determine whether the sounds are communicative, Gagliano said she has observed plant roots responding to sounds of similar frequencies by changing the direction of their growth.

What exactly this means remains unknown. Galliano said she was surprised to hear plants talk outside of experimental settings.

(www.independent.co.uk/news/long_reads/science-and-technology/climate-change-scientist-secret-life-plants-a9090106.html)

© Shutterstock

She said the experience was "beyond the realm of strict science" and that the sounds she heard could not be detected by third-party observers using laboratory equipment. However, she is certain that she has heard plants speak to her on multiple occasions.

She said: "It wasn't just me, there were several people who heard the same sound in the same place."

Whether you believe these claims or not, recent studies by multiple research teams have revealed various new discoveries about plants and sound. For example, in 2019, Israeli researchers found that when plants were exposed to the buzzing of bees, the sugar content in their nectar increased.

(onlinelibrary.wiley.com/doi/full/10.1111/ele.13331)

Some flowers can produce sugars in their nectar when they hear the sounds of pollinators. © Lee Albrow/Getty Images

Plants may do this to reward insects that help pollinate when collecting nectar, such as bees. Of course, some insects just plunder nectar and neither collect nor spread pollen, which is of no benefit to plants. Only when the researchers exposed the plants to the sounds of bees or sounds of the same frequency did the sugar content in the nectar increase.

Other studies have found a variety of ways that sound might affect plants. For example, when plants were exposed to the sound of caterpillars gnawing on their leaves, they produced more chemicals to deter them when faced with real, hungry caterpillars.

(www.calacademy.org/explore-science/do-plants-hear)

Research like this has led people to wonder whether we could influence plants with specially designed sounds. One Chinese institute, the Qingdao Physical Agricultural Engineering Research Center, has designed a special device that plays sounds to plants. Its makers say it could increase yields and reduce fertilizer requirements.

(www.sciencedirect.com/science/article/pii/S1876610212000677)

Research has shown that the roots of trees and other plants communicate using chemical signals. © Inhabitat

Sound can also help plants and other organisms establish mutualistic relationships. In Kalimantan, the back wall of the pitcher of the carnivorous plant Nepenthes helmsleyi reflects the sound waves of bats. This attracts bats to rest in the cage and leave their excrement to nourish the plant. A 2016 paper studying the relationship between plants and bat sounds found that a closely related pitcher plant, which does not rely on bat excrement for nourishment, does not have the reflective surface that can attract bats, a flying mammal.

(www.sciencedirect.com/science/article/abs/pii/S1369526616300942)

These studies all help to demonstrate that sound is important to plants. But the exact mechanism by which plants might sense or feel sound is still unclear. It's one thing to claim that plants can automatically respond to sound stimuli, but it's another to claim that plants can listen and think about the sound and then decide how to respond. Most people would argue that so-called intelligence is largely an ability reserved for animals.

David Robinson of the University of Heidelberg in Germany is skeptical. Like many others, he strongly criticizes the idea that plants have intelligence or can communicate like humans. The plant's response to sound stimuli, while interesting, is just an innate program, rigid and inflexible. It has nothing to do with thought processes, he says.

Animals have neurons in their brains that transmit information via electrical signals, but plants do not have neurons. Robinson believes that plants, in general, lack the machinery to think. However, it is said that information can still be transmitted within plants through chemical signals.

(www.sciencemag.org/news/2018/09/plants-communicate-distress-using-their-own-kind-nervous-system)

Also controversial is the idea that plants can learn. A researcher tried to replicate Gagliano and his colleagues' plant learning experiment but did not get the same results. Gagliano and his team publicly responded that the method used to replicate the experiment was different from their previous one, so they could not reliably evaluate their previous results.

(elifesciences.org/articles/57614) (elifesciences.org/articles/61141)

Although plants respond to certain sound stimuli and are sometimes able to communicate chemically with other organisms, many people do not consider this to be the same thing as chatting.

Evolutionary ecologist Monica Gagliano. © The New York Times

Robinson said he does not deny the possibility that plants have abilities we are unaware of, but he also insisted that we should not equate plants' communication abilities with our own, nor should we try to have conversations with plants.

“I think a lot of people are anthropomorphizing plants to make them seem more like us,” he said.

At the same time, he did not brush aside the disagreement between researchers who believe plants have innate cognitive abilities and those who deny they do. “These are two warring parties,” he said, adding, “and I mean a war of words.”

This is not to suggest that researchers are divided along factional lines. Views on plant abilities vary widely, and many scientists besides Robinson still do not believe that plants are intelligent—which, in anyone’s view, presupposes something akin to the human ability to communicate.

However, Tony Trewavas, an emeritus professor at the University of Edinburgh, disagrees. He argues that plants can be considered intelligent in a broader sense, because they do respond to stimuli to improve their chances of survival. He compares this to a zebra running away from a lion. We naturally think of that as an intelligent response, but we don't think of a plant killing a small piece of its leaf to prevent caterpillar eggs from hatching on it as a sign of intelligence.

(www.scientificamerican.com/article/egg-killing-leaves-come-from-plant-butterfly-arms-race/)

Trevavers also noted that trees rely on a network of microorganisms in the soil to locate nutrients, which serves as a form of communication between different species.

(www.science.org/news/2019/05/wood-wide-web-underground-network-microbes-connects-trees-mapped-first-time)

"All life has intelligence, because if it weren't, it wouldn't exist," Trevafors says. That's really thought-provoking. So, by definition, is survival evidence of intelligence?

Regardless, how one can talk to plants or decode their "speech" remains a mystery.

Belov said that while she was fascinated by the possibility that plants could talk, she remained skeptical.

“There are definitely people who say they can communicate with plants,” she said, “but from a more logical or scientific point of view, it’s not possible.”

There is also the question of what we would say if we could communicate with the pine trees and discuss with the dahlias.

“Maybe these plants are willing to communicate with us,” Belov thought to himself. “Who knows?”

By Chris Baraniuk

Translated by Yord

Proofreading/Amanda

Original article/www.bbc.com/future/article/20210831-the-people-who-believe-plants-can-talk

This article is based on the Creative Commons License (BY-NC) and is published by Kushan on Leviathan

The article only reflects the author's views and does not necessarily represent the position of Leviathan