Daniel Chamowitz
Image: Alan Chapelski
More In This Article
-
The Wisdom of Psychopaths
In this engrossing journey into the lives of psychopaths and their infamously crafty behaviors, the renowned psychologist Kevin Dutton reveals that there is a...
Read More »
How aware are plants? This is the central question behind a fascinating new book, “What a Plant Knows,” by Daniel Chamovitz, director of the Manna Center for Plant Biosciences at Tel Aviv University. A plant, he argues, can see, smell and feel. It can mount a defense when under siege, and warn its neighbors of trouble on the way. A plant can even be said to have a memory. But does this mean that plants think — or that one can speak of a “neuroscience” of the flower? Chamovitz answered questions from Mind Matters editor Gareth Cook.
1. How did you first get interested in this topic?
My interest in the parallels between plant and human senses got their start when I was a young postdoctoral fellow in the laboratory of Xing-Wang Deng at Yale University in the mid 1990s. I was interested in studying a biological process that would be specific to plants, and would not be connected to human biology (probably as a response to the six other “doctors” in my family, all of whom are physicians). So I was drawn to the question of how plants sense light to regulate their development.
It had been known for decades that plants use light not only for photosynthesis, but also as a signal that changes the way plants grow. In my research I discovered a unique group of genes necessary for a plant to determine if it’s in the light or in the dark. When we reported our findings, it appeared these genes were unique to the plant kingdom, which fit well with my desire to avoid any thing touching on human biology. But much to my surprise and against all of my plans, I later discovered that this same group of genes is also part of the human DNA.
This led to the obvious question as to what these seemingly “plant-specific” genes do in people. Many years later, we now know that these same genes are important in animals for the timing of cell division, the axonal growth of neurons, and the proper functioning of the immune system.
But most amazingly, these genes also regulate responses to light in animals! While we don’t change our form in response to light as plants do, we are affected by lab at the level of our internal clock. Our internal circadian clocks keep us on a 24 hour rhythm, which is why when we travel half way around the world we experience jet lag. But this clock can be reset by light. A few years ago I showed, in collaboration with Justin Blau at NYU, that mutant fruit flies that were missing some of these genes lost the ability to respond to light. In other words, if we changed their clocks, they remained in jetlag.
This led me to realize that the genetic difference between plants and animals is not as significant as I had once naively believed. So while not actively researching this field, I began to question the parallels between plant and human biology even as my own research evolved from studying plant responses to light to leukemia in fruit flies.
2. How do think people should change how they think about plants?
People have to realize that plants are complex organisms that live rich, sensual lives. You know many of us relate to plants as inanimate objects, not much different from stones. Even the fact that many people substitute silk flowers for real ones, or artificial Christmas trees for a live one, is exemplary at some level of how we relate to plants. You know, I don’t know anyone who keeps a stuffed dog in place of a real one!
But if we realize that all of plant biology arises from the evolutionary constriction of the “rootedness” that keep plants immobile, then we can start to appreciate the very sophisticated biology going on in leaves and flowers. If you think about it, rootedness is a huge evolutionary constraint. It means that plants can’t escape a bad environment, can’t migrate in the search of food or a mate. So plants had to develop incredibly sensitive and complex sensory mechanisms that would let them survive in ever changing environments. I mean if you’re hungry or thirsty, you can walk to the nearest watering hole (or bar). If you’re hot, you can move north, if you’re looking for a mate, you can go out to a party. But plants are immobile. They need to see where their food is. They need to feel the weather, and they need to smell danger. And then they need to be able to integrate all of this very dynamic and changing information. Just because we don’t see plants moving doesn’t mean that there’s not a very rich and dynamic world going on inside the plant.
Rights & Permissions
See what we're tweeting about
50 Comments
Add CommentPersonally, I am much fonder of trees than of Contrarians.
Reply | Report Abuse | Link to thisDo plants think? No.
Reply | Report Abuse | Link to thisYou're welcome.
2. How do think people should change how they think about plants?
Reply | Report Abuse | Link to thisi think you meant thin people because no one wants us fattie's opinions :(
Reminds me of an episode when one of my sister's boyfriends visited the family and started on the topic of plants being able to "feel". After listening politely for an extended period of time my brother said "Yeah, last week there was a forest fire on television and all the plants got up and ran out of the room." End of conversation.
Reply | Report Abuse | Link to thisEasy
Reply | Report Abuse | Link to thisNo.
Although I have not studied the science yet, several years ago I became logically aware of an extremely high likelihood that all life, down to it's basic processes, must have at least some crude thought processes which affect function, survival, and evolvement. The extreme vastness of life species and tenacity is explainable in no other logical way. Life and thought (intelligence) must likely be either codependent or indistinguishable, and I applaud scientists like this one who are hot on the trail of proof and theory refinement.
Reply | Report Abuse | Link to thisThought occurs on many levels. Each of our bodily organs and processes know what they are doing in their extremely complex job function, and can adapt to changing situations, and seemingly communicate with other complex body processes, even though our high-level conscious mind seems to have great difficulty communicating with these lower components. Studying intelligence at all levels is crucial to our own evolvement.
Should it actually be the case that "Plants Think" they ought to replace the Editors of SA, who obviously cannot, as evidenced by the piece on Planned Parenthood.
Reply | Report Abuse | Link to thisAs all carnivores and herbivores eat plants or plant products to survive and grow ,we can say that plants give us everything we have like mind , consciousness etc. One cannot give what one doesn't have.Ergo, plants can do , feel and think everything that we can or at least have the potential for it .Some of these potentials are developed for it's own use and others lie dormant in plants . Similarly, humans animals, fish and birds can also " flower " like the plants and even " foliate " . All life- forms on earth including some bacteria and microorganisms survive directly or indirectly on plants and what energies drive plant life drives all life- forms too, philosophically speaking . Scientists can work out specifics as verifications of philosophical conclusions arrived at through philosophical reasonings . So, to the question , can plants think , the answer is yes, they can for their practical purposes .As they have developed the ability to respond to environments as and when they need to they don't have to think in advance and take advance precautions .Also, as they don't carry put commercial transactions they need not plan and organize ahead to meet targets and dead- lines. As they live in the "now" as far as their " emotions" are concerned they don't have to write poetry or stories or even philosophize . As every plant is it's own technologist and scientist they don't need to do any technology transfer. Comparatively we are more inter- dependent ,less self- dependent , weaker individually . Plants can nourish us , plants can poison us . All life- forms are dependent on plants than plants on life- forms . Plants need for their survival, only what is naturally available such as soil, wind,air ,sun and water and other chemicals and salts naturally available on earth and no need for other life- forms , as such although they do exploit life- forms if life- forms are available. In short, plants are smarter than us in every way , whether they can "think" like us or not about the size and extent of the galaxies in the universe , about the relationship between space , time and mass and energy or whether there is a god or not or about multiverses etc , which are only relevant to satisfying our endless perennial curiosity, which we are excessively endowed with . Anything in excess is poison and annihilative .
Reply | Report Abuse | Link to thisYes , if someone responds to my above comments please.
Reply | Report Abuse | Link to thisI seem to remember reading a book where a man built a divice that let him hear plants.He was driven mad by the screams of blades of grass being mowed.If anybody can remember the name of this book please reply.
Reply | Report Abuse | Link to thisThe great Bangalee scientist Jogodish Chondro Bose first proved that plant has life in early Twentieth Century.We must recognise his discovery.
Reply | Report Abuse | Link to thisI remember reading about a very interesting experiment about this done decades ago. A house plant that was a philodendron was wired up with a sensitive ohm meter. It had a specific resistance that varied very little from day to day. One day a man entered the room and burned the plant with a candle. It reacted by a sharp change in resistance. Eventually it returned to normal, but after that trauma, every time the man entered the room it again reacted with a change in resistance without the man ever touching it.
Reply | Report Abuse | Link to thisEventually the experiment was also verified with Kirlian photography.
There is obviously some kind of thinking process going on here.
I think the book's title is "Why my lawn mower refused to start" by John Deere.
Reply | Report Abuse | Link to thisI think the book's title is "Why my lawn mower refused to start" by John Deere
Reply | Report Abuse | Link to thisjack.123, I don't know that book but it was a favorite scifi theme in the old days - think of Rubén Darío's story "Viola acherontia" and John Wyndham's novel _Day of the Triffids_, for example.
Reply | Report Abuse | Link to thisChamovitz actually makes sense when he discusses the overlap between the ways plants and animals sense and respond to their environments. Only the headline writer and interviewer stray into the scifi world of "thinking" plants.
The ideas have been around for a long time: http://en.wikipedia.org/wiki/Jagadish_Chandra_Bose#Plant_research
Reply | Report Abuse | Link to thisAll life, as we know it on this planet is based on proteins, whose synthesis is driven by nucleic acids. The characteristics of any organism are dependent upon which DNA genes are switched on and which are kept off. This switching on or off of genes is influenced by the environment and it derives the evolution of organisms. So it should not come as a surprise that plants have sensual lives. After all to 'live' is to 'act purposefully'. Now, can one act purposefully without THINKING?
Reply | Report Abuse | Link to thisOf all the plants on the Earth, the one most likely to exhibit thinking is the TickleMe Plant (Mimosa pudica)
Reply | Report Abuse | Link to thisMy Students' love growing this plant as it opens when the sunrises and closes when the sunsets. Of course it closes its leaflets and lowers its branches when Tickled. We explain this with Tugor pressure but perhaps their is some thinking going on. I found more information about this plant by searching the TickleMe Plant book and on line.
I love how the TickleMe Plant reacts to being Tickled by closing its fern like leaves when Tickled. Just google TickleMe Plant. My kids love it.
Reply | Report Abuse | Link to thisThere is tickle me plants in my yard here in Hawaii. They are truly amazing and extremely hardy. They grow in the crushed lava driveway where cars can run them over without seeming to harm them. They seem to defy the need for regular watering. they grow in full sun and I have seen them go for months without a drop of rain.
Reply | Report Abuse | Link to thisThe Venus Flytrap is another plant with some sort of internal intelligence. It has hairs in the trap that only trigger a response when two or more are stimulated. A single hair stimulated will not trigger the closure of the leaf. This demonstrates that in some primatave way the
Oops, hit the wrong key!
Reply | Report Abuse | Link to thisThis demonstrates that in some primatave way the Venus Flytrap can count!
Interesting concepts! My major philosophy is this: if one can increase the procentual proportion of a given society to think a free (unfettered) thought, then one has moved society forward. This presupposes that not all, and indeed only a small minority of a given society is able to think a free thought. In this light, the issue of plants thinking is on a scale of 1 to the minus 11th to 10 to the 15th. Obviously, plants have need for and maintain some form of communication, just as all living organisms do, but likening this activity to a thought process is stretching the point way beyond what philosophy can support. In the human body, such communication is rampant in myriad ways that even the most advanced computer is not able to keep up with, but this still has nothing to do with the process of thinking.
Reply | Report Abuse | Link to this@ErnestPayne: Just curious - does your brother believe legs are essential for thinking?
Reply | Report Abuse | Link to thisI think I read that, too, but it was a short story, not a book—perhaps in that great old magazine Astounding Science Fiction.
Reply | Report Abuse | Link to thisI think I read that, too, but it was a short story, not a book—perhaps in that great old magazine Astounding Science Fiction.
Reply | Report Abuse | Link to thisI think I read this, too, but it was in a short story, not a book—perhaps in that great old magazine Astounding Science Fiction.
Reply | Report Abuse | Link to thisThose "I can answer this question. No" remarks have a smug sound to them, as if they're asserting the superiority of their common sense to the speculations of some egg-head scientist. In fact, Chamovitz concludes that plants do not think —in the usual sense of thinking—but he also shows that their behavior includes many of the usual functions of thinking. And he is humble enough to acknowledge that they have other abilities that remain undiscovered. Very good article; thank you, Professor Chamovitz!
As science replaces spirit, we lose these faculties.
Reply | Report Abuse | Link to thisMany people let plants talk to them. It's a simple meditation technique used for millennium.
Some believe herbology was developed by nations feeding prisoners different herbs to see what happened.
So explain ayawaska. An ancient hybrid made of plants that grow hundreds of miles away from each other. To take it properly requires a certain diet of fish and bananas for a few days. What book did they read all of that in?
Shamans were immediately killed to make way for the new medicine.
We killed our herbal inheritance: brilliant. These people new medicine far beyond ours. Needed no machines. Just went into spirit and found out.
Science is ancient too. But it was respected, not abused.
Sit silent and open, in an open field. Forget the world and embrace the Earth. Maybe you will hear/feel/sense something. You will be invigorated at the very least.
Cup a plant in you're hand, don't pick it. Breath with it, become it, it will love you for that and might reveal something.
Just don't let you're science mind bully you're spirit mind, or vice versa. Good people are balanced.
The author might like to correct some typos:
Reply | Report Abuse | Link to this"we are affected by lab"
"cover myself hear"
"First off"
John Deere
Reply | Report Abuse | Link to thisgreat answer, Sir you have a sense of humor
Reply | Report Abuse | Link to thisThank you Dr.. I presume you were addressing my comment above. Response: Analyzing and attempting to define "thought" has been going on for a very long time, and yet we truly understand very little. We may choose to define it as a high-end human process which utilizes language in the mind, or we may be more general and include the basic elements of learning, decision-making, communication, free will or creativity for example, which are obvious in a vast number of other biological species. (Is thought different, or just a more advanced version of the same core components?) Now if we analyze these functions and try to see what makes them tick, we will get down to some very basic biologic, chemical, electrical (and other?) processes. Now try to define life, and see if it can be done without using some of those very basic processes which were discovered above.
Reply | Report Abuse | Link to thisA planet without life operates in a defined way according to the known laws of Physics and Chemistry, etc.. But add an element of survivable life and then predictability ceases, because life seems to adapt (often in bizarre ways), where a rock does not. I find it impossible to draw a line between life forms which possess the core elements of thought, and those which do not, because I don't truly understand exactly what life or thought is. I have a hard time distinguishing between basic life which performs functions and adapts to changing conditions, and what I do every day. If I hypothesize that all life has some very basic intelligence, thought, free will, etc., that would go a very long way towards explaining evolution, and perhaps a tremendous amount more.
Our current Human System Biology – based Knowledge Management (HSBKM) model framework derived from Nature Knowledge Theory (NKT) could explained how plants could having consciousness. Visit http://mobeeknowledge.ning.com/forum/topics/knowledge-management-based-comprehensive-explanation-how-plants-h?xg_source=activity and have a look directly to the Attachment
Reply | Report Abuse | Link to thisI've bought the book on the strength od this interview, and have been sorely disappointed.
Reply | Report Abuse | Link to thisSciAm used to awsome in its ability to present the "state of the art" science -if often in ponderous fashion.
Now it has gone to the other extreme: its articles (and in this case book) present a few basic facts - cocktail food morcels all, if well distributed on the platter.
Take plant SEEING - Phototropism. The book points out that the receptor is in the tip of the plant (the DARWINS' experiment). Fine, but is it the end of the story. Which cells are involved, how does the receptor function, how the stimulus is then transmitted, and where, and how the reaction is fashioned is ignored - maybe deemed beyond the reader's capacity to understand.
This was a short story in a collection of science fiction. Don't remember the title or author, though.
Reply | Report Abuse | Link to thisSEEING, HEARING, SMELLING, FEELING VS. OPTICAL, ACOUSTIC, CHEMICAL AND TACTILE PROCESSING
Reply | Report Abuse | Link to thisIt is interesting that plants can detect and respond to optical, acoustic, chemical and tactile input. Some (like the venus flytrap) can even "move" their parts. It is also interesting that these sensory and sensorimotor processing mechanisms in plants have similarities and continuities with those in animals. But the crucial question (especially for a vegan like myself!) is whether the plant is *feeling* anything when it detects and responds to optical, acoustic, chemical and tactile input. That's the problem philosophers call the "hard" one.
The "hard" problem will be tackled by over 50 of the world's experts (including Stefano Mancuso, who will talk on "Evolution of Plant Intelligence") in the Turing Year 2012 Summer Institute on the Evolution and Function of Consciousness June 29-July 11 in Montreal: http://bit.ly/TuringConsciousness
I think the smug answers of no, which I took part in, come from the misguided, sensationalistic title of "Do Plants Think?".
Reply | Report Abuse | Link to thisOf course they don't think. Drawing parallels between plants responding to their environment and conscious thought is puffery at its finest. You have to ignore science completely to even consider penning that title.
A less controversial question than; Do Plants Think? might be: Are Plants Aware?
Reply | Report Abuse | Link to thisOur language is egocentrically loaded, especially with words related to 'Mind', such as 'Reason'and 'Think'. The word 'Awareness' remains relatively uninfected by our egocentricity and its use can open a much wider perspective when applied to living forms.
The implications of an AWARE perspective in exposing an overlooked common thread in the great diversity of life, and in making sense of Natural Selection's larger role in the evolution of Awareness, are detailed in a book soon to be released by; Brighton Publishing.
Review copies of;
"The Other Half of Evolution" are available on request for literary review and the basic concepts included in this nonfiction work can be previewed now as deftly included content in a novel;
"Darwin's Paw".
Yes plants think, but in a passivly aware state. Some plants verge on an active state of awareness but none approach the cognitave awareness of mammals and some mollusks.
Awareness is a matter of degree and the advanced state of many plants may surprise you when you examine the pace and scope of their awareness.
There have been several experiments like the one you mentioned and they all showed the same individual specific response although some used ultrasonic detection rather than electrical resistance.
Reply | Report Abuse | Link to thisI was right with you until you mentioned Kirlian photography. Then you became a raving nut job. Kirlian photography makes images via photosensitive substances. Making an image of electrical flow does not prove thought, spirit or even static or changing plant conditions. As electricity travels it changes resistance in the medium it travels through in minute ways. This can lead to differences in image detail or in some cases cause flow channels to persist or disappear.
Maybe if shamans were not usually demonstrably schizophrenic people would have been more tolerant. I have yet to meet anyone that was truly balanced and the worst are the ones that have deluded themselves into thinking they are balanced. After decades of exploration of altered mental states and higher consciousness, all I found are drug addicts, scam artists, liars, nut jobs and occasionally a person or two with impressive control of their own body.
Reply | Report Abuse | Link to thisTry reading the article without your preconceived ideas and have an open mind.
Some of you may be interested in the Society for Ethical Treatment of Plants
Reply | Report Abuse | Link to thishttp://www.facebook.com/groups/155995414439270/
I was taught that plants react via their hormones. This results in very sophisticated organisation, and a form of distributed intelligence without a central organ. We usually only think about the human form of intelligence, but even bacteria think, even if they have no conciousness. It might be said that pain reception is the first sign of intelligence. Perhaps plants feel pain as they react to injury by emitting chemicals which taste nasty to herbivores.
Reply | Report Abuse | Link to thisSo you don't have to read the entirety of the article to find his answer to the question:
Reply | Report Abuse | Link to this"6. Would you say, then, that plants 'think'?
No I wouldn’t, but maybe that’s where I’m still limited in my own thinking! To me thinking and information processing are two different constructs. I have to be careful here since this is really bordering on the philosophical, but I think purposeful thinking necessitates a highly developed brain and autonoetic, or at least noetic, consciousness. Plants exhibit elements of anoetic consciousness which doesn’t include, in my understanding, the ability to think. Just as a plant can’t suffer subjective pain in the absence of a brain, I also don’t think that it thinks."
This does not excuse his use of verbs elsewhere in the article to describe the movements and growth of plants that one would normally reserve for sentient beings. Sentient beings feel pain, and we should treat them accordingly.
I was born as a "sensitive" and have always been able to connect with other living beings easily. As I grew up my abilities increased and I got to the stage of being able to hear inside my head the plant tell me what it needs or to hear a tree call out to me in a tiny high voice "Hi! Come here!"
Reply | Report Abuse | Link to thisPlants love to get our love. They thrive on it. With so little they do so well. We have much to learn from them.
Its called a Sensitive Plant.
Reply | Report Abuse | Link to thisYes, It was a short story called “The Sound Machine”
Reply | Report Abuse | Link to thisby Roald Dahl
I mention it in an article I wrote:
http://honeysharp.com/performing-plants/
Hola Cindys. Ciertamente tus palabras son muy acertadas respecto de que "el pensamiento ocurre en muchos niveles". Esto es así debido a que los humanos y las plantas somos ambos "sistemas inteligentes", sólo que habitamos con diferentes características dentro del circuito ecológico de la vida.Coincido contigo en la expresión "El estudio de la inteligencia en todos los niveles es crucial para nuestra propia evolución". Deberíamos hacer el esfuerzo de entender a las plantas como un sistema inteligente y no como un mero individuo biológico de distinto tipo. Los humanos somos seres con una "Mente simultánea", y aún no los reconocemos como tal. Toda inteligencia es capaz de interpretar con los sentidos que posee, y puede como tal, realizar procesos mentales. Las plantas también lo hacen. Un abrazo para Usted.
Reply | Report Abuse | Link to thisDo our skin cells think? When it is cold my skin turns into bumps and the cells react to the temperature. Those cells don't have to "think" to do their job. They just do. You FEEL the temperature on your skin, but it is your brain that realizes the chill and brings it to the conscious mind.
Reply | Report Abuse | Link to thisYou then hopefully "think" enough to get a sweater or jacket!
I consider a plant to be like our skin. Aware of what is going on at all times, but able to modify itself if necessarily (or able) to continue to survive.
I took the study of plants in high school instead of the human body. Bought a couple of plants. Two of them still survive and that was 35 years ago. I wonder what they must think or remember!
Modern science clearly indicates that most, if not all organisms must, in principle, have some degree of consciousness (self-awareness). Even if only as the locus of its sensory and effector interactions with the external world.
Reply | Report Abuse | Link to thisThis, of course, includes such creatures as bacteria and plants. Here's why:
From our understanding of biological evolution by natural selection it becomes quite clear that provision of a navigational feature that involves some degree of self awareness is required for an organism to interact optimally with its environment.
It is a measure of its fitness for the prevailing environment and subject to selection pressure accordingly.
A large number of species, particularly the multicellular varieties, possess, in addition, the provision of memory over and above the kind "hard-wired" into the system to provide basic behaviors.
This enhanced form of consciousness is best described by the term "imagination", defined as the ability to form, store and morph models of the external world within the neural systems of higher animals and to a lesser extent biochemically in simpler species. On careful reflection it is seen that this captures the essence of the everyday use of the word.
Imagination can usefully be considered to be a memory-enhanced version of its more primitive correlate, consciousness (self awareness).
While there is no doubt whatsoever that plants have a variety of innate sensory and effector systems as underlined in this article they, in general, do not have the memory attributes that characterize imagination and consequently do not exhibit learned behavior.
Within the animal kingdom, of course, imagination is ubiquitous.
A prerequisite for survival and replication.
For a snail it is tiny, for a rat, very appreciable.
For the human species, whose level of interaction with its environment is extraordinarily high, it is immense.
Furthermore, human imagination is greatly amplified by virtue of the fact that it is exported and imported between individuals. It is also stored externally on such media as paper, more recently, magnetic, optical and electronic devices.
This collective sharing and storing of imagination is what we call "language".
We would do well to discard the overused, vague and silly word "intelligence". Imagination, essentially a navigational feature, says it all.
This is expanded upon in the broad evolutionary outlined in "The Goldilocks Effect: What Has Serendipity Ever Done For Us?", a free download in e-book formats from the "Unusual Perspectives" website.
the conversation ended because of your bro's stupid remark. plants obviously can't run. if your brother was aware of the work of cleve baxter, rupert sheldrake, and the film "the secret life of plants" he wouldn't have made such an ignorant comment. there is data to show plants can detect when other plant life is harmed, including that seen on a television. if you had more interesting and informed dinner guests the conversation could have went further.
Reply | Report Abuse | Link to thisWhy the chauvinism for animal consciousness only? We as humans have repeatedly found out that we are are not the center of the universe, not the only conscious animals, not the only smart things in the universe. It was only until the early 1900s that people believed animals were robots (AKA philosophical zombies which have no conscious experience). What precludes plants from also having a phenomenology of existence?
Reply | Report Abuse | Link to this