Home » Voices of Eco-Agriculture » Opinions » Opinion: Plant sentience and the Impossible Burger (André Leu)

Opinion: Plant sentience and the Impossible Burger (André Leu)

By André Leu

What is consciousness? It is awareness of self, others and our surroundings. What is sentience? It is the ability to perceive, experience and feel things.


The concept of sentience is a key part of animal rights. This is because it is necessary for animals to be sentient in order to experience pain and distress and the reason why reasonable people oppose animal cruelty. It is also part of the concept of the sanctity of life.

Scientific research shows that plants possess these same attributes. Plants are conscious, sentient beings.

In 1973, The Secret Life of Plants, by Peter Tompkins and Christopher Bird documented experiments that showed plant sentience. The book gave many examples of plant responses to human care, their ability to communicate, their reactions to music, their lie-detection abilities and their ability to recognize and to predict. It was a best seller. However, despite quoting from a range of research, it was met with skepticism by many scientists and academics.

Since then, thousands of published studies present a body of evidence that plants are conscious, sentient beings.

Andre Leu speaks at the inaugural Tropical Agriculture Conference in Belize
André Leu with Regeneration International helps kick off the inaugural Tropical Agriculture Conference in Belize on Tuesday, Nov. 13, 2018.

Foremost amongst this new breed of scientists is Monica Gagliano, research associate professor in evolutionary ecology at the University of Western Australia. Gagliano has published numerous peer-reviewed scientific papers on how plants have a Pavlov-like response to stimuli. They can learn, remember and communicate to neighboring plants. She has pioneered the research field of plant bioacoustics. She has demonstrated that plants emit their own “voices” and, moreover, detect and respond to the sounds of their environments.

Gagliano and other researchers have shown that learning, communicating, feeling, smelling, hearing and decision-making are not the exclusive province of animals. Below is a brief summary of some of this research.

Plant Cognition

According to Gagliano, plant cognition is a new field of research directed at experimentally testing the abilities of plants, including perception, learning processes, memory and consciousness. She states that it holds considerable implications for the way we perceive plants, as it redefines the traditional boundaries between animals and plants.

Plant Communication

Plants can communicate in many ways, such as in the volatile airborne compounds given off by leaves and other compounds exchanged by roots and networks of symbiotic fungi.

Examples of communication in the literature are numerous. Cotton plants release volatile compounds that attract parasitic wasps to attack the caterpillars. Bean plants can communicate with each other if one is under attack. The network symbiotic fungi hyphae that connect plants is used as an ‘internet’ to alert other plants of attack.

Gagliano has pioneered the field of plant bioacoustic communication. She has demonstrated that plants produce sound waves in the lower end of the audio range as well as an overabundance of ultrasonic sounds. By capturing the signals emitted by plants under different environmental conditions, she is exploring the ecological significance of these sounds for communication among plants and between plants and other organisms.

Plants Can Hear

Tel Aviv University researcher Lilach Hadany shows that plants can hear bees and consequently sweeten their nectar to attract them. Some researchers say the reason why so many flowers are bowl-shaped is to amplify sound — just like a satellite dish or animal ears.
Other studies show that they can hear the chewing of pest insects on nearby plants and produce compounds to repel them.

Plants Can Smell

Researchers at the University of Tokyo have discovered how information from odor molecules changes gene expression in plants. Based on the many transcription factor genes in plants, the researchers state that plants may be able to detect many more odors than animals.

Other studies show that plants can use smell to detect pests and odors given off by other plants. Plants use odors of volatile compounds to communicate with each other, to communicate with microorganisms and to repel pests.

Plants Can Make Decisions

A study by biologists from Radboud University and the University of Neuchâtel in Switzerland reveals that plants can change the smell of the defensive odors they emit in response to the type of enemy that attacks them.

Plants Have Memories and the Ability to Learn

Gagliano has performed a range of experiments that show that plants have memories and can learn. In one of her experiments Gagliano showed that after being repeatedly dropped six inches onto a cushioned surface, sensitive plants (mimosa) stopped their normal response of closing their leaves, as there was no threat. Sensitive plants curl up when touched or dropped as a response to threats. They learned and this meant that they must have remembered the previous events.

Plants Have Social Lives

Some of the most interesting research is about plant communication with other plants and species. Plants can cooperate with other life forms.

One of the most significant is with fungi to exchange nutrients, water, protection from diseases and to communicate with other plants via the billions of threadlike hyphae that make up the fungal “internet.” This communications “internet” of volatile compounds, bioacoustics and symbiotic microorganisms is incredibly complex, with numerous simultaneous conversations occurring between multiple species.

Researchers are starting to understand how important this multitude of communication pathways is to ensuring the health of ecosystems, including agricultural ecosystems.

Plants Can Feel

Numerous studies show that plants can take defensive actions to preserve their well-being and life when being eaten by pests.

Plants Feel Stress and Pain

Numerous studies show that plants fell stress. One of the most interesting is research from the University of Wisconsin-Madison showing that plants can actually experience and register pain and that the level of pain can be measured.

Plants Are Conscious Sentient Beings Like Animals

Just because plants do not have a nervous system and brains does not mean that they are not conscious, do not feel pain and stress and do not value their lives. Plants are aware of their environment, have self-awareness and take actions to preserve their lives. This shows that they value their lives and that they do not want to be hurt or killed. They are conscious, sentient beings, like animals.

We have much to learn about the nature of consciousness. Research into death and near-death experiences show that many people have been conscious even though their brains had stopped functioning. This leads some researchers to believe that consciousness is more than just our brains.

Given that plants meet the definition of consciousness means that our concepts about consciousness needs to be broader.

Why are the lives of animals considered more important than the lives of plants? Surely given that nearly all life on earth is directly or indirectly dependent on plant photosynthesis, especially humans, the sanctity of the life of plants should be paramount.

Why is it considered wrong to kill mammals, birds and fish, yet it is OK to directly or indirectly take part in the mass killing of plants, insects and microorganisms?

Industrial Agriculture as Mass Murder

Industrial agriculture is responsible for most of the destruction of forests and the massive loss and extinction of life on this planet. Its pesticides are responsible for the collapse of insects, bird and amphibians. The vast majority of the destruction of irreplaceable old growth forests is for three crops: GMO soy, GMO corn and palm oil.

Much of this production is wasted by using it to feed machines (biofuels) or for Confined Animal Feeding Operations (CAFOs). CAFOs are cruel, inhumane animal prisons that are responsible for numerous environmental problems. They are also very inefficient. They produce one ton of animal protein from ten tons of vegetable protein. In other words, ten times the amount of land is needed to cultivate the protein for meat from these systems, compared to using the original plant-based proteins for human food.

These industrial-scale monocultures are biological deserts of destruction that promote the cultivation of single species by destroying all the other species in their fields with pesticides and inappropriate cultivation. Billions of plants are killed as “weeds’” and billions of insects are killed as “pests” in the process of growing most of the plant-based crops that are sold as food. The fact is, these lifeforms are sentient beings that feel pain and value their lives. They are being killed against their will, so by definition this can be considered a violation of the sanctity of life.

Holistic Planned Grazing

Contrast industrial agriculture with Holistic Planned Grazing — a humane regenerative grazing system. Researchers have demonstrated that the appropriate, time-managed grazing systems will not kill a single plant and will increase the biodiversity of native plants, animals, insects and microorganisms in the farm ecosystem. Very significantly, 68 percent of the world’s agricultural lands are rangelands and are largely unsuitable for cropping to produce vegetable proteins, fats and carbohydrates.

Producing meat, milk, eggs and fiber from these lands using regenerative grazing systems is the best way to manage these ecosystems and provides much-needed nutritious food, especially for local populations. The fact is, eating animals from these systems results in a considerable reduction of the loss of life compared to a monoculture of soybeans. We are talking about only killing a few sentient beings per acre compared to killing hundreds of thousands.

The Impossible Burger

The Impossible Burger is the ultimate product of industrial agriculture. This highly processed concoction uses pesticide-contaminated GMO soy, GMO corn and wheat produced from industrial monocultures. They are processed in a factory with chemical additives to give artificial flavor, texture and shelf life. One of the additives is a blood-like substance that is produced by genetically modified bacteria in large vats that are fed with carbohydrates produced from pesticide-dependent industrial agriculture. The additives used in this burger have no adequate testing to show that they are safe for human consumption, especially for children.

The Impossible Burger is promoted as the end of eating meat. Everybody can now have plant-based diets without killing animals for food. However, it is the result of the mass killing of plants, insects and microorganisms. Its products are produced by poisoning the environment with pesticides that are directly responsible for the alarming decline in insects, birds and amphibians. The GMO “blood” comes through damaging the genome of living organisms through inserting foreign DNA in ways that do not happen naturally. This invasion of the genome can be seen as a violation of the very basis of the sanctity of life.

Farming systems used by the Impossible Burger destroy topsoil and make a massive contribution to climate change due to oxidation of soil carbon into carbon dioxide. Holistic Planned Grazing contributes to the reversal of climate change because it increases soil carbon.

Regenerative Agriculture as a Humane System

An ethical position is that all life is important and that we should treat all living things humanely. Humans cannot exist without causing the death of other species; however, we also have a right to exist. Respecting the sanctity of life means we should be looking at how we can minimize harm and the destruction of life, no matter what type of life it is.

Regenerative agricultural systems can improve biodiversity and encourage the increase in living species instead of the destructive reductionism of industrial agriculture. There are a range of regenerative agricultural practices that minimize the killing of plants, insects and other life-forms. These include pasture cropping, agroecology, cover crops, perennial systems, agroforestry, permaculture, syntropic agriculture, holistic planned grazing and polycultures, among others.

My favorite regenerative systems are perennial agroforestry systems that incorporate fruit and nut trees, legumes, vegetables, staples such as grains and tubers, herbs, flowers, holistically grazed animals and endemic biodiversity and wildlife. This is what I have done with my own farm. These are the most productive and biodiverse systems on the planet and should be seen as the future of farming.

The choice about eating meat is a personal one. We should all boycott meat that comes from CAFOs, as they are cruel and inhumane. Given that plants are sentient beings, there is no logic to say that they have fewer rights than animals. Plants should have the same rights as animals.

The real choice should be about minimizing the harm to all living things and doing our best to regenerate our environment. It means choosing to only eat foods that have come from humane, regenerative systems, preferably from our own local systems.

André Leu is the author of The Myths of Safe Pesticides and Poisoning Our Children. He previously served as president of IFOAM — Organics International, and is currently the international director of Regeneration International.

MEET ANDRE LEU IN PERSON

Andre Leu will be making an appearance at the 2019 Acres U.S.A. Eco-Ag Conference & Trade Show this Dec. 9-12 in Minneapolis, Minnesota. On Dec. 11th, he will be speaking about Maximizing Photosynthesis to Power High Yielding Regenerative Agriculture.  Learn more and register.