Are plants sentient?
August 19, 2017 12:07 PM Subscribe
Research into a symbiosis between plants and fungi is challenging our ideas of consciousness and intelligence.
This symbiosis is thought to be 450 million years old. The fungi help plants grow by assisting in the delivery of water, phosphorus, and nitrogen. In exchange plants send the fungus food. The network enables plants to communicate with each other. Fungus will even help plants defend themselves.
Mycorrhiza networks send nutrients to trees in need:
Trees will also keep neighbouring stumps alive,
and will sabotage nearby unwanted plants.
Additional resources:
TED Talk - Suzanne Simard: How trees talk to each other.
Radiolab - From Tree to Shining Tree
Quirks and Quarks - Trees Have Their Own Fungal Internet
in the last few years there has been a explosion of interest in what is sometimes called plant "neurobiology." Plants and trees don't have brains and that's enough, in some quarters of the intellectual establishment, to settle in the negative the question of whether they sense, evaluate, think, learn, plan, act or feel. But that inference — from no brain, to no mind — may be too quick.NPR - A Web of Trees and Their "Hidden" Lives
Roots and fungi combine to form what is called a mycorrhiza: itself a growing-together of the Greek words for fungus (mykós) and root (riza). In this way, individual plants are joined to one another by an underground hyphal network: a dazzlingly complex and collaborative structure that has become known as the Wood Wide Web.The New Yorker - The Secrets of the Wood Wide Web
This symbiosis is thought to be 450 million years old. The fungi help plants grow by assisting in the delivery of water, phosphorus, and nitrogen. In exchange plants send the fungus food. The network enables plants to communicate with each other. Fungus will even help plants defend themselves.
We know that trees also exchange information. When one tree is attacked by insects, we can measure electrical signals that pass through the bark and into the roots and from there into fungi networks in the soil that alert nearby trees of the danger. The trees pay for this service by supplying the fungi with sugars from their photosynthesis. And the fungi in turn protect their host trees from attacks by other dangerous species of fungi and contamination by heavy metals.Yale Environment 360 - Are Trees Sentient?
. . . it has been known for a while that trees of different species can communicate with and support one another via their mycorrhizae. I had already known that plants can communicate with unrelated species through the air; plants getting chomped by herbivores release volatile chemicals that are sensed by neighboring plants, who up their defenses pro-actively. But communicating — and even sharing resources — through mutual root fungi was news to me.Scientific American - Dying Trees Can Send Food to Neighbors of Different Species
Mycorrhiza networks send nutrients to trees in need:
One of the important things that we tested in that particular experiment was shading. The more Douglas fir became shaded in the summertime, the more excess carbon the birch had went to the fir. Then later in the fall, when the birch was losing its leaves and the fir had excess carbon because it was still photosynthesizing, the net transfer of this exchange went back to the birch.Yale Environment 360 - Exploring How and Why Trees "Talk" to Each Other.
Trees will also keep neighbouring stumps alive,
[Peter]Wohlleben: This one beech tree was cut four to 500 years ago by a charcoal maker, but the stump is still alive — we found green chlorophyll under the thick bark. The tree has no leaves to create sugars, so the only explanation is that it has been supported by neighboring trees for more than four centuries. I made this discovery myself, and later learned that other foresters have observed this happening as well.Yale Environment 360 - Are Trees Sentient?
and will sabotage nearby unwanted plants.
This "allelopathy" is quite common in trees, including acacias, sugarberries, American sycamores and several species of Eucalyptus. They release substances that either reduce the chances of other plants becoming established nearby, or reduce the spread of microbes around their roots.BBC Earth - Plants Have A Hidden Internet
Additional resources:
TED Talk - Suzanne Simard: How trees talk to each other.
Radiolab - From Tree to Shining Tree
Quirks and Quarks - Trees Have Their Own Fungal Internet
This post was deleted for the following reason: Poster's Request -- frimble
I talk to my plants all the time. I compliment them when they're looking nice and I encourage them when they're growing so that they survive and are hardy. And I feel badly and usually say an apology when they die (either on their own, or through my own neglect).
posted by Fizz at 1:24 PM on August 19, 2017 [3 favorites]
posted by Fizz at 1:24 PM on August 19, 2017 [3 favorites]
I love plants and trees, especially the four citrus in my sun room, but saying trees can "talk" or "send" or "give" is seeing intention where there isn't any.
It doesn't surprise me that one tree's roots touch the roots of its neighbor. Plants turn sunlight and CO2 and water into sugar molecules for fuel. It's not surprising that one plant doesn't really care whether the sugar molecules are from inside it or a neighbor via the roots. We're animals--an entirely different branch of organisms--and we can eat sugar and carb molecules from plants too.
If the roots are touching, chemicals (like sugar in water) diffuse naturally. If a tree has a lot of one chemical in its internal water that a neighbor it's in contact with doesn't have, it's an entropy thing that the chemical will migrate to the neighbor with a lower concentration.
Plants have hormones as well. Hormones are chemical signals. Most of the "behaviors" the articles mention could be a result of a plant's hormones reaching the neighboring plant and altering the response in the receiver.
There was a book and a tv show recently about evolution. One of the points I remember is that when we're a ball of cells growing into a baby, there's a hormone that creates a signal in the hand-stump where the side where the signal is strongest is your thumb-side and where it's weakest is the pinky-side of your hand, or it might have been the other way. That's how your hand-stump "knows" where to grow fingers and a thumb. There's another hormone that tells the cells in the fetus which end of the torso is the head-end (to grow arms and a chest) and which is the butt-end (to grow hips and legs). The hormone is very similar in all animals, all the way down to flies, and the fly version would work in other animals. So it's pretty reasonable to think plants have similar sorts of hormones that achieve the same function across many species.
I have rose bushes and each of the little stems has a single mission: to flower and make seeds. As the flower parts are swelling into forming seeds, it creates a hormone which travels back up the stem that tells the rest of the stem: "We did it! No more flowers this year!". As a human I want flowers so if I clip the flower after the bloom falls off, then the stem won't get that signal and it'll flower again.
The thing about the trees working together to coordinate seed droppings or whatever could be that a tree releases a hormone after seeds fall or maybe the hormone is what causes the stems of fruit to wither and drop the seed pods. The hormone spreads through the tree and through the roots and into the neighbors and the neighboring tree gets the signal that "seeds have fallen!" so it then just sits there or it drops undeveloped seeds which won't compete with the neighbor that dropped fully developed seeds first.
posted by Blue Tsunami at 1:43 PM on August 19, 2017 [9 favorites]
It doesn't surprise me that one tree's roots touch the roots of its neighbor. Plants turn sunlight and CO2 and water into sugar molecules for fuel. It's not surprising that one plant doesn't really care whether the sugar molecules are from inside it or a neighbor via the roots. We're animals--an entirely different branch of organisms--and we can eat sugar and carb molecules from plants too.
If the roots are touching, chemicals (like sugar in water) diffuse naturally. If a tree has a lot of one chemical in its internal water that a neighbor it's in contact with doesn't have, it's an entropy thing that the chemical will migrate to the neighbor with a lower concentration.
Plants have hormones as well. Hormones are chemical signals. Most of the "behaviors" the articles mention could be a result of a plant's hormones reaching the neighboring plant and altering the response in the receiver.
There was a book and a tv show recently about evolution. One of the points I remember is that when we're a ball of cells growing into a baby, there's a hormone that creates a signal in the hand-stump where the side where the signal is strongest is your thumb-side and where it's weakest is the pinky-side of your hand, or it might have been the other way. That's how your hand-stump "knows" where to grow fingers and a thumb. There's another hormone that tells the cells in the fetus which end of the torso is the head-end (to grow arms and a chest) and which is the butt-end (to grow hips and legs). The hormone is very similar in all animals, all the way down to flies, and the fly version would work in other animals. So it's pretty reasonable to think plants have similar sorts of hormones that achieve the same function across many species.
I have rose bushes and each of the little stems has a single mission: to flower and make seeds. As the flower parts are swelling into forming seeds, it creates a hormone which travels back up the stem that tells the rest of the stem: "We did it! No more flowers this year!". As a human I want flowers so if I clip the flower after the bloom falls off, then the stem won't get that signal and it'll flower again.
The thing about the trees working together to coordinate seed droppings or whatever could be that a tree releases a hormone after seeds fall or maybe the hormone is what causes the stems of fruit to wither and drop the seed pods. The hormone spreads through the tree and through the roots and into the neighbors and the neighboring tree gets the signal that "seeds have fallen!" so it then just sits there or it drops undeveloped seeds which won't compete with the neighbor that dropped fully developed seeds first.
posted by Blue Tsunami at 1:43 PM on August 19, 2017 [9 favorites]
I believe it is possible there is a great deal more types of sentience than we currently understand, and I think doing work to understand life forms other than human and granting them an innate benefit of the doubt that they strive for life and are sensing something seems to be the decent things to do. In general the more we other lifeforms other than human (or even other humans) the more we can mistreat them.
posted by xarnop at 2:00 PM on August 19, 2017 [20 favorites]
posted by xarnop at 2:00 PM on August 19, 2017 [20 favorites]
Outstanding post, Stonkle! And on behalf of the botanists/plant scientists of the world, thank you very much! Awesome.
posted by strelitzia at 2:01 PM on August 19, 2017 [2 favorites]
posted by strelitzia at 2:01 PM on August 19, 2017 [2 favorites]
okay but is there any way for us to develop a secret project to blast the contents of all of our network nodes — the sum total of all human knowledge — into the fungal network, thereby both vastly accelerating the growth of the network's complexity and also ensuring that our faction will lead the ascent toward godhood as all human life on Planet Earth joins with the emerging globe-spanning fungal consciousness?
asking for a friend.
posted by You Can't Tip a Buick at 2:02 PM on August 19, 2017 [15 favorites]
asking for a friend.
posted by You Can't Tip a Buick at 2:02 PM on August 19, 2017 [15 favorites]
There's a science fiction short whose premise is that trees just operate on a different time scale, and by taking a dose of mcguffin you could join their world. I even asked mf about the story. Got an answer even, but on phone and old, so...
Anyway, fascinating post.
posted by maxwelton at 2:58 PM on August 19, 2017
Anyway, fascinating post.
posted by maxwelton at 2:58 PM on August 19, 2017
"I am Groot."
posted by mermayd at 3:07 PM on August 19, 2017 [4 favorites]
posted by mermayd at 3:07 PM on August 19, 2017 [4 favorites]
Under natural conditions, he explains, a 100-year-old tree is likely to be "no thicker than a pencil." But it is these smaller trees, raised in the darkness of their parents' canopy, that eventually develop the dense wood, flexibility, resistance to fungi that are necessary for them to reach true maturity — and the open sky — when they are several hundred years old.This just dredged up a complaint from a woodworkers' forum that's been floating around my brain for a while: The new oak, the complainer said, the stuff that's grown now on plantations, doesn't last outside. It rots away. But there is old oak, he said, old lintels and window frames that have been sitting outside for a century or more without rotting or giving in to fungus.
I thought that selection would've been responsible for it: The trees that survived to become old growth forest would've been the ones which had exceptional fungus resistance to begin with, and the ones that further survived as dead wood on the outside of old houses would've been a further winnowing down of resistant wood. But this article seems to be suggesting that trees raised in certain conditions develop their resistance. Fascinating.
posted by clawsoon at 3:34 PM on August 19, 2017 [7 favorites]
Upon further consideration of this topic, I am utterly convinced that plants are among the more "intelligent" of the world's organisms. As someone who works with cacti each bearing spines of various lengths, including several inches, no one could ever convince me that evolving to be able to impale the enemy is not a good survival mechanism. Rinse and repeat for urticatious and toxic species.
posted by strelitzia at 4:01 PM on August 19, 2017
posted by strelitzia at 4:01 PM on August 19, 2017
Anything can be sentient if you're willing to stretch the definition of "sentient" enough.
posted by Spathe Cadet at 4:18 PM on August 19, 2017 [7 favorites]
posted by Spathe Cadet at 4:18 PM on August 19, 2017 [7 favorites]
“If trees could scream, would we be so cavalier about cutting them down? We might, if they screamed all the time, for no good reason.”
posted by thelonius at 4:43 PM on August 19, 2017 [6 favorites]
posted by thelonius at 4:43 PM on August 19, 2017 [6 favorites]
The Intelligent Plant: Scientists debate a new way of understanding flora. By Michael Pollan (The New Yorker, December 2013)
Video: Michael Pollan discusses how timelapse photography reveals the hidden life of plants [Plant Neurobiology - Commentary - The New Yorker].
posted by Auden at 4:46 PM on August 19, 2017 [2 favorites]
Video: Michael Pollan discusses how timelapse photography reveals the hidden life of plants [Plant Neurobiology - Commentary - The New Yorker].
posted by Auden at 4:46 PM on August 19, 2017 [2 favorites]
Anything can be sentient if you're willing to stretch the definition of "sentient" enough.
What if we stretch it infinitely? Many thinkers have held that thought is a universal property that inheres in all physical entities. In this view, the forms that thought takes are as varied as all the physical forms. As one thinker puts it:
posted by No Robots at 5:40 PM on August 19, 2017 [27 favorites]
What if we stretch it infinitely? Many thinkers have held that thought is a universal property that inheres in all physical entities. In this view, the forms that thought takes are as varied as all the physical forms. As one thinker puts it:
For if we were cattle, we should love the carnal and sensual life, and this would be our sufficient good; and when it was well with us in respect of it we should seek nothing else. Again, if we were trees, we could not, of course, be moved by the senses to love anything; but we would seem to desire, as it were, that by which we might become more abundantly and bountifully fruitful. If we were stones or waves or wind or flames or anything of that kind, we should indeed be without both sensation and life, but we should still not lack a kind of desire for our own proper place. For the weight of bodies is, as it were, their love, whether they are carried downwards by gravity or upwards by their lightness. For the body is carried by its weight wherever it is carried, just as the soul is carried by its love.--Augustine / The City of God, Book 11 chapter 28Lest anyone imagine that this kind of thinking belongs only to an ancient, superstitious mind, we can point to such eminent thinkers as Spinoza and Hegel. Even among scientists such thinking is not unknown. Perhaps here is common ground for science and spirituality.
posted by No Robots at 5:40 PM on August 19, 2017 [27 favorites]
We shouldn't ever be surprised that any living thing has surprisingly clever adaptive responses to its environment, and communicating with others has some clear advantages just like with animals. What plants might lack in rapid movement, they make up for in being staggeringly complex chemical factories and complex genetics. These types of interactions are very, very cool.
posted by Schismatic at 5:41 PM on August 19, 2017 [2 favorites]
posted by Schismatic at 5:41 PM on August 19, 2017 [2 favorites]
This means they're going to remake The Seeds of Doom, doesn't it?
posted by juiceCake at 6:54 PM on August 19, 2017
posted by juiceCake at 6:54 PM on August 19, 2017
All of those links and phenomena are interesting, but NONE of them suggest animal-like intelligence or anything close to sentience. It just shows that a seemingly simple set of rules can lead to complex behaviors.
posted by runcibleshaw at 7:22 PM on August 19, 2017 [2 favorites]
posted by runcibleshaw at 7:22 PM on August 19, 2017 [2 favorites]
That's just what the vegetarians want us to think
posted by Ray Walston, Luck Dragon at 8:04 PM on August 19, 2017 [3 favorites]
posted by Ray Walston, Luck Dragon at 8:04 PM on August 19, 2017 [3 favorites]
That's just what the vegetarians want us to think
I was just gonna quip "Your move, vegans" and move on, but you reminded me of a better line:
"I'm not a vegetarian because I love animals. I'm a vegetarian because I hate plants." -A. Whitney Brown
posted by solotoro at 8:14 PM on August 19, 2017 [4 favorites]
I was just gonna quip "Your move, vegans" and move on, but you reminded me of a better line:
"I'm not a vegetarian because I love animals. I'm a vegetarian because I hate plants." -A. Whitney Brown
posted by solotoro at 8:14 PM on August 19, 2017 [4 favorites]
The Secret Life of Plants (1979, Stevie Wonder soundtrack)
posted by Rash at 9:28 PM on August 19, 2017 [2 favorites]
posted by Rash at 9:28 PM on August 19, 2017 [2 favorites]
The last work of utterly mind-blowing scifi I read touched on this from a slightly different angle: Blindsight.
It's not pleasant to realize there is "intelligence" in everything, and that it probably thinks YOU are a disease.
You bet there's a Wood Wide Web, and it's probably full of hate screeds about your race by tree Nazis. (And I mean, they're justified, we're assholes to trees, but still.)
posted by saysthis at 9:42 PM on August 19, 2017 [5 favorites]
It's not pleasant to realize there is "intelligence" in everything, and that it probably thinks YOU are a disease.
You bet there's a Wood Wide Web, and it's probably full of hate screeds about your race by tree Nazis. (And I mean, they're justified, we're assholes to trees, but still.)
posted by saysthis at 9:42 PM on August 19, 2017 [5 favorites]
Anything can be sentient if you're willing to stretch the definition of "sentient" enough.
I think that sentience has always been a pretty nebulous and stretchy quality - so why not? Adherents of Jainism ascribe entities with a "sentience" score: water is at level 1 - because it "possesses only one sense: touch" - humans are level 5. And this classification is quite similar to the scientific idea of a "Sentience Quotient" - which is about mass of processing entities versus their performance: humans have an SQ of +13, most animals - including computers, somewhere a bit lower than that - and carnivorous plants have an SQ of +1 (all from 1970s era analysis I believe).
When we talk about plants being sentient - the world is going to take quite a lot of convincing to ascribe them consciousness. But it seems like there is quite strong evidence for saying that they can perceive the world.
posted by rongorongo at 11:22 PM on August 19, 2017 [3 favorites]
I think that sentience has always been a pretty nebulous and stretchy quality - so why not? Adherents of Jainism ascribe entities with a "sentience" score: water is at level 1 - because it "possesses only one sense: touch" - humans are level 5. And this classification is quite similar to the scientific idea of a "Sentience Quotient" - which is about mass of processing entities versus their performance: humans have an SQ of +13, most animals - including computers, somewhere a bit lower than that - and carnivorous plants have an SQ of +1 (all from 1970s era analysis I believe).
When we talk about plants being sentient - the world is going to take quite a lot of convincing to ascribe them consciousness. But it seems like there is quite strong evidence for saying that they can perceive the world.
posted by rongorongo at 11:22 PM on August 19, 2017 [3 favorites]
Merlin Sheldrake… wearing a blue paisley-pattern neckerchief, a collarless woollen jacket, and a khaki canvas rucksack with gleaming brass buckles. He resembled a Victorian plant hunter… plays accordion in a band called the Gentle Mystics… long loved fungi, which seemed to him possessed of superpowers… “…fungi don’t have to have sex to pass things on,” Sheldrake explained… He longed for more direct contact… he had enough to pile, with a pair of tweezers, onto a tiny fragment of biscuit, which he then ate. “They’re really good for you, spores, full of all these lipids,” he said. On occasion he has cut them into lines and snorted them.
Yes, he is the son of Rupert Sheldrake, proponent of the controversial theory of morphic resonance.
Brother Cosmo Sheldrake is a musician whose works include The Woods, The Moss, and Tardigrade Song.
posted by Segundus at 12:20 AM on August 20, 2017 [2 favorites]
Yes, he is the son of Rupert Sheldrake, proponent of the controversial theory of morphic resonance.
Brother Cosmo Sheldrake is a musician whose works include The Woods, The Moss, and Tardigrade Song.
posted by Segundus at 12:20 AM on August 20, 2017 [2 favorites]
The really interesting thing about all this to me is that it seems hard to account for all this complex biological activity strictly in terms of selective pressures as they're popularly understood.
Whether there's any subjective experience of intentionality among, er, tree folk or not, some goal beyond mere propagation of individual genetic legacy seems to be at work in producing these adaptations. I'm not arguing for intelligent design or anything when I say that, as it seems more abstract than that, but it confirms what more contemporary genomics has suggested about the incompleteness of more reductionist models of inheritance and natural selection. Some complex of mechanisms and pressures more complex than a simple selection filter for genes that aren't fitted to their immediate environmental conditions seems to be at work in the development of complex systems of cross species symbiosis and networked signaling. Whatever drives the development of this sort of biological diversity, it isn't a ruthless, asocial drive for individual survival, so what is it? Species level selection pressure? Loneliness?
Not arguing for this idea, per se, but imagine if our analysis of evolutionary processes is wrong and there is a sort of quasi-intentional goal to the processes that drive mutation and adaptation. What if, at its core, all biological life--maybe even purely as a byproduct of whatever spark it takes to make the kind of self-replicating, biologically instantiated algorithms we recognize as life processes--functions with an implicit set of goals, blindly seeking some kind of optimal balance between individual existence/survival and social connection/propagation of the species.
It's fair to say there's not enough evidence to deduce intentionality or some secret goal seeking dimension to evolutionary processes, and the 20th century was full of examples of people taking that sort of thinking in monstrous, inhumane directions. But either way, it seems clear the more absolutist, reductive accountings of how selective pressures and evolutionary processes function in nature can't easily account for all the observed biological diversity in the real world. At the very least, even if we posit these kinds of system can emerge over time through only the interaction of random chance and the blind mechanism of natural selection, it provides compelling evidence those selective pressures don't prefer asocial survival strategies over more cooperative modes of behavior, even to the degree that cooperation across species boundaries can be adaptive and can confer survival benefits to individual organisms.
That said, I wouldn't be too shocked if at some point in the future, we found definitive proof of a kind of vegetable consciousness at the level of individual trees and a more complex form of consciousness emerging at the level of entire forests because complex subjectivity and goal seeking behaviors emerging from sufficiently complex systems of simple, non-sentient biological constituent parts is from all the best evidence how consciousness in humans or any other species arises.
It's the compositional fallacy to argue that because the individual physical processes or systems that trees, fungus, and other forms of life use to affect complex behaviors don't show any evidence of consciousness or intentionality when considered in isolation, that absence of intentionality at the constituent level is negative evidence for intentionality at the systemic/species level. Even human consciousness and brain function can easily be reduced analytically to parts that all appear purely mechanical and automatic, even if not strictly deterministic, at that level of analysis. You can't argue against consciousness from the bottom up if it's an emergent phenomena that only arises and operates at a higher level of organizational abstraction.
Sometimes when I'm feeling romantic and poetic, I like to imagine all life wants something in common: to be allowed not merely to survive but to be, to exist, and to know and understand itself. But that's what makes me a sort of half-assed existentialist, because I can never quite convince myself you could ever prove an idea like that with enough scientific rigor to establish it as settled fact rather than mere romantic idealism and wishful thinking driven by the human cognitive biases toward seeing intentionality and social meaning in irreducible, fundamentally impersonal complexity.
Trees and plants, whether by accident or not, made conditions on earth suitable for all complex animal life. Whether they did it knowingly or for some deliberate purpose or not, that's the kind of thing that in human society normally merits some minimum level of appreciation and gratitude.
Personally I'd say plant life has shown far more creativity and decency in how it's adapted to survival pressure, from a biased, human social perspective, than many animal life forms. Trees and plants pursue altruistic survival strategies and it's worked so well from them, none of the rest of us can survive without them. They are a crucial part of our ecological operating system that provides the problem space in which most animal biological and evolutionary processes function.
posted by saulgoodman at 7:17 AM on August 20, 2017 [3 favorites]
Whether there's any subjective experience of intentionality among, er, tree folk or not, some goal beyond mere propagation of individual genetic legacy seems to be at work in producing these adaptations. I'm not arguing for intelligent design or anything when I say that, as it seems more abstract than that, but it confirms what more contemporary genomics has suggested about the incompleteness of more reductionist models of inheritance and natural selection. Some complex of mechanisms and pressures more complex than a simple selection filter for genes that aren't fitted to their immediate environmental conditions seems to be at work in the development of complex systems of cross species symbiosis and networked signaling. Whatever drives the development of this sort of biological diversity, it isn't a ruthless, asocial drive for individual survival, so what is it? Species level selection pressure? Loneliness?
Not arguing for this idea, per se, but imagine if our analysis of evolutionary processes is wrong and there is a sort of quasi-intentional goal to the processes that drive mutation and adaptation. What if, at its core, all biological life--maybe even purely as a byproduct of whatever spark it takes to make the kind of self-replicating, biologically instantiated algorithms we recognize as life processes--functions with an implicit set of goals, blindly seeking some kind of optimal balance between individual existence/survival and social connection/propagation of the species.
It's fair to say there's not enough evidence to deduce intentionality or some secret goal seeking dimension to evolutionary processes, and the 20th century was full of examples of people taking that sort of thinking in monstrous, inhumane directions. But either way, it seems clear the more absolutist, reductive accountings of how selective pressures and evolutionary processes function in nature can't easily account for all the observed biological diversity in the real world. At the very least, even if we posit these kinds of system can emerge over time through only the interaction of random chance and the blind mechanism of natural selection, it provides compelling evidence those selective pressures don't prefer asocial survival strategies over more cooperative modes of behavior, even to the degree that cooperation across species boundaries can be adaptive and can confer survival benefits to individual organisms.
That said, I wouldn't be too shocked if at some point in the future, we found definitive proof of a kind of vegetable consciousness at the level of individual trees and a more complex form of consciousness emerging at the level of entire forests because complex subjectivity and goal seeking behaviors emerging from sufficiently complex systems of simple, non-sentient biological constituent parts is from all the best evidence how consciousness in humans or any other species arises.
It's the compositional fallacy to argue that because the individual physical processes or systems that trees, fungus, and other forms of life use to affect complex behaviors don't show any evidence of consciousness or intentionality when considered in isolation, that absence of intentionality at the constituent level is negative evidence for intentionality at the systemic/species level. Even human consciousness and brain function can easily be reduced analytically to parts that all appear purely mechanical and automatic, even if not strictly deterministic, at that level of analysis. You can't argue against consciousness from the bottom up if it's an emergent phenomena that only arises and operates at a higher level of organizational abstraction.
Sometimes when I'm feeling romantic and poetic, I like to imagine all life wants something in common: to be allowed not merely to survive but to be, to exist, and to know and understand itself. But that's what makes me a sort of half-assed existentialist, because I can never quite convince myself you could ever prove an idea like that with enough scientific rigor to establish it as settled fact rather than mere romantic idealism and wishful thinking driven by the human cognitive biases toward seeing intentionality and social meaning in irreducible, fundamentally impersonal complexity.
Trees and plants, whether by accident or not, made conditions on earth suitable for all complex animal life. Whether they did it knowingly or for some deliberate purpose or not, that's the kind of thing that in human society normally merits some minimum level of appreciation and gratitude.
Personally I'd say plant life has shown far more creativity and decency in how it's adapted to survival pressure, from a biased, human social perspective, than many animal life forms. Trees and plants pursue altruistic survival strategies and it's worked so well from them, none of the rest of us can survive without them. They are a crucial part of our ecological operating system that provides the problem space in which most animal biological and evolutionary processes function.
posted by saulgoodman at 7:17 AM on August 20, 2017 [3 favorites]
Not scientific but the very best thing ever on this topic is Stevie Wonders album The Secret Life of Plants!
posted by sammyo at 7:51 AM on August 20, 2017 [2 favorites]
posted by sammyo at 7:51 AM on August 20, 2017 [2 favorites]
It takes a long time to say anything in Old Entish. And they never say anything unless it is worth taking a long time to say.
posted by ejs at 9:33 AM on August 20, 2017 [3 favorites]
posted by ejs at 9:33 AM on August 20, 2017 [3 favorites]
Plants have hormones as well. Hormones are chemical signals. Most of the "behaviors" the articles mention could be a result of a plant's hormones reaching the neighboring plant and altering the response in the receiver.
Well, sure! But you know, lots of the behaviors we observe in animals are the result of some external stimulus triggering changes in hormonal activity which then change processes in the brain--especially more "long-term" responses in gene regulation intended to help individuals adapt to their environment.
I love this literature. I don't care much about the philosophy of sentience (which isn't the same as sapience, just a heads up), but I love listening to and reading about this as a behavioral zoologist. Plants might not be my thing: I have a short attention span, I just want to watch something move! But they do so many neat and totally alien things as they adapt to their environment, and they exert their own agency to survive in the world around them just as surely as any animal does. Any living thing wants to continue living, and plants (and fungi!) are no different. They simply exert that influence in a more alien way than we as animals are used to, because as sessile organisms they don't have the same options that a human might.
If you loved this, I might suggest checking out Hope Jahren's Lab Girl, in which she talks quite extensively about what it means for a tree to be a tree.
posted by sciatrix at 10:04 AM on August 20, 2017 [5 favorites]
Well, sure! But you know, lots of the behaviors we observe in animals are the result of some external stimulus triggering changes in hormonal activity which then change processes in the brain--especially more "long-term" responses in gene regulation intended to help individuals adapt to their environment.
I love this literature. I don't care much about the philosophy of sentience (which isn't the same as sapience, just a heads up), but I love listening to and reading about this as a behavioral zoologist. Plants might not be my thing: I have a short attention span, I just want to watch something move! But they do so many neat and totally alien things as they adapt to their environment, and they exert their own agency to survive in the world around them just as surely as any animal does. Any living thing wants to continue living, and plants (and fungi!) are no different. They simply exert that influence in a more alien way than we as animals are used to, because as sessile organisms they don't have the same options that a human might.
If you loved this, I might suggest checking out Hope Jahren's Lab Girl, in which she talks quite extensively about what it means for a tree to be a tree.
posted by sciatrix at 10:04 AM on August 20, 2017 [5 favorites]
don't underestimate the influence of the geologic time scale. random mutation/natural selection/Billions of years = some crazy terrific weird biology and symbiosis.
posted by j_curiouser at 2:33 PM on August 20, 2017
posted by j_curiouser at 2:33 PM on August 20, 2017
Thinking plants? The evidence is weak -- I should know, I've spent the last decade perfecting a new super fertilizer I'm calling the "biorestorative formula" for the Sunderland Corporation.
posted by benzenedream at 2:41 PM on August 20, 2017 [1 favorite]
posted by benzenedream at 2:41 PM on August 20, 2017 [1 favorite]
we're cool as long as you don't accept a position at weyland-yutani.
posted by j_curiouser at 2:50 PM on August 20, 2017 [1 favorite]
posted by j_curiouser at 2:50 PM on August 20, 2017 [1 favorite]
I remembered seeing this: Go West My Sap about trees moving westward (mostly).
posted by MovableBookLady at 3:43 PM on August 20, 2017
posted by MovableBookLady at 3:43 PM on August 20, 2017
My most recent, still unreplicated, WTF moment with a plant's sensory abilities was the report in 2014 that there was a vine in Argentinian temperate rainforests, Boquila trifoliolata, that could mimic the leaves of whatever tree on which it was growing. On occasion, the same vine would be creeping on multiple trees and somehow the associated foliage would adapt to mimic the local leaf environment. THIS IS INSANE. HOW DOES IT KNOW WHAT PLANT IT'S ON AND WHAT LEAVES TO MIMIC? HOW DOES A PLANT KNOW WHAT ANOTHER PLANT'S LEAVES LOOK LIKE? The authors of the original paper suggest volatile hormones of the mimicked plant somehow cue the vine, WHICH SEEMS POSSIBLE BUT STILL WTF? Further, it's lead others to resurrect an old, crack-pot hypothesis that plants do have "visual" organs or ocelli. (Haberlandt, 1905)
So, just so I'm safe when the real green revolution arrives, I have always believed that the Trees are watching, knowing and judging us.
posted by Cold Lurkey at 5:34 PM on August 20, 2017 [8 favorites]
So, just so I'm safe when the real green revolution arrives, I have always believed that the Trees are watching, knowing and judging us.
posted by Cold Lurkey at 5:34 PM on August 20, 2017 [8 favorites]
Anything can be sentient if you're willing to stretch the definition of "sentient" enough.
That's generally what some humans say when someone notices that an animal or plant is capable of some behaviour or adaptation we'd previously reserved for ourselves.
posted by sneebler at 7:50 PM on August 20, 2017 [2 favorites]
That's generally what some humans say when someone notices that an animal or plant is capable of some behaviour or adaptation we'd previously reserved for ourselves.
posted by sneebler at 7:50 PM on August 20, 2017 [2 favorites]
There's a science fiction short whose premise is that trees just operate on a different time scale, and by taking a dose of mcguffin
I remember reading something along those lines in a book from the 70s (maybe in a John Lilley phase), that argued that mushrooms and their effects were chemical communication(!) from another organismic space. Having experienced the occasional McGuffin over the years, some version of this idea makes sense to me in my previous life as a botanist. Plants and their evolutionary relationships do exist on a different time scale than ours. (If you haven't seen it, the film "The Queen of Trees" is a great introduction to this time scale.)
I've met several people who have encountered machine elves and similar entities while high on various substances. Why not? In terms of personal experience, what would communication from something as wildly different from us as a fungus look like?
Our definition of "sentient" is indexed to the baseline of human intelligence, and is likely more circular than we'd like to admit.
posted by sneebler at 8:41 PM on August 20, 2017 [1 favorite]
I remember reading something along those lines in a book from the 70s (maybe in a John Lilley phase), that argued that mushrooms and their effects were chemical communication(!) from another organismic space. Having experienced the occasional McGuffin over the years, some version of this idea makes sense to me in my previous life as a botanist. Plants and their evolutionary relationships do exist on a different time scale than ours. (If you haven't seen it, the film "The Queen of Trees" is a great introduction to this time scale.)
I've met several people who have encountered machine elves and similar entities while high on various substances. Why not? In terms of personal experience, what would communication from something as wildly different from us as a fungus look like?
Our definition of "sentient" is indexed to the baseline of human intelligence, and is likely more circular than we'd like to admit.
posted by sneebler at 8:41 PM on August 20, 2017 [1 favorite]
what would communication from something as wildly different from us as a fungus look like?
If you haven't read The Bad Graft, I think you'd be interested in it.
posted by solotoro at 9:37 PM on August 20, 2017
If you haven't read The Bad Graft, I think you'd be interested in it.
posted by solotoro at 9:37 PM on August 20, 2017
That's generally what some humans say when someone notices that an animal or plant is capable of some behaviour or adaptation we'd previously reserved for ourselves.
It's also what some humans say when other humans are redefining words to mean things thay have not previously meant, though.
posted by Spathe Cadet at 9:59 PM on August 20, 2017
It's also what some humans say when other humans are redefining words to mean things thay have not previously meant, though.
posted by Spathe Cadet at 9:59 PM on August 20, 2017
It's also what some humans say when other humans are redefining words to mean things thay have not previously meant, though.
There was a legal case in which the question was whether women are persons. Sometimes words are applied in novel ways that extend our understanding of and sympathy toward others. Sometimes this does involve modifying our understanding of words.
posted by No Robots at 5:32 AM on August 21, 2017 [1 favorite]
There was a legal case in which the question was whether women are persons. Sometimes words are applied in novel ways that extend our understanding of and sympathy toward others. Sometimes this does involve modifying our understanding of words.
posted by No Robots at 5:32 AM on August 21, 2017 [1 favorite]
I don't disagree that sometimes it's necessary to modify our understanding of words. I do think that it's maybe premature to make the leap from "sometimes sugars produced by one tree wind up in a different tree because they're transported by fungal networks below the soil" to "trees have altruism and self-awareness and friendships and human-like feelings."
I'm a little puzzled, honestly, about why so many MeFites seem happy to make that jump based on what I feel is badly-framed science journalism, or why the science journalists can't let the discovery of the networks be remarkable and interesting all on its own without anthropomorphizing. It's not that plants couldn't have altruism, etc.; it's that there are a lot of possible explanations that explain the observed facts just fine without resorting to so plants are just like people OMG. (The leap to fill in any gaps in understanding of how the process works with "therefore sentience!" reminds me more than a little of the creationist tendency to fill in gaps with "therefore God!") I mean, if sharing resources through a complex interconnected network and communicating with other species in a mutually-beneficial relationship is enough evidence to show sentience, then traffic lights are sentient.
(Though some people here in this thread have suggested that traffic lights are sentient without any pushback, so maybe that's the majority position on traffic lights here and therefore a bad reductio ad absurdum. I dunno.)
I could get on board with plant sentience if it could be shown that, for example, the trees have the choice as to whether or not to put sugars into the fungal network (as opposed to passively leaking them through their roots, or the fungus exerting effort to extract the sugars), that they're deliberately choosing to support other trees and other species of tree (as opposed to just, any tree whose roots touch the network gets roped into being part of the network whether they "want to" or not; maybe stumps continue to receive support from the rest of the trees because it's actually impossible, given the way the network is constructed, for individual trees to be cut off from the sugar supply if their cells are not actually 100% dead and rotting), and that kind of thing. How would one construct an experiment to demonstrate that trees can make choices? I haven't the foggiest. But I imagine someone will someday.
posted by Spathe Cadet at 8:30 AM on August 21, 2017 [3 favorites]
I'm a little puzzled, honestly, about why so many MeFites seem happy to make that jump based on what I feel is badly-framed science journalism, or why the science journalists can't let the discovery of the networks be remarkable and interesting all on its own without anthropomorphizing. It's not that plants couldn't have altruism, etc.; it's that there are a lot of possible explanations that explain the observed facts just fine without resorting to so plants are just like people OMG. (The leap to fill in any gaps in understanding of how the process works with "therefore sentience!" reminds me more than a little of the creationist tendency to fill in gaps with "therefore God!") I mean, if sharing resources through a complex interconnected network and communicating with other species in a mutually-beneficial relationship is enough evidence to show sentience, then traffic lights are sentient.
(Though some people here in this thread have suggested that traffic lights are sentient without any pushback, so maybe that's the majority position on traffic lights here and therefore a bad reductio ad absurdum. I dunno.)
I could get on board with plant sentience if it could be shown that, for example, the trees have the choice as to whether or not to put sugars into the fungal network (as opposed to passively leaking them through their roots, or the fungus exerting effort to extract the sugars), that they're deliberately choosing to support other trees and other species of tree (as opposed to just, any tree whose roots touch the network gets roped into being part of the network whether they "want to" or not; maybe stumps continue to receive support from the rest of the trees because it's actually impossible, given the way the network is constructed, for individual trees to be cut off from the sugar supply if their cells are not actually 100% dead and rotting), and that kind of thing. How would one construct an experiment to demonstrate that trees can make choices? I haven't the foggiest. But I imagine someone will someday.
posted by Spathe Cadet at 8:30 AM on August 21, 2017 [3 favorites]
Thank you for the thoughtful response, Spathe Cadet. I cannot speak for others in the thread, and so what follows is strictly just my own dog in this fight. The principle is that just as differences in bodies are strictly quantitative, so are differences in thought. On this basis, thought is nothing more than an entity's input, processing and output of externally applied stimuli. Thus, a rock responds to heat or motional pressure. A plant also responds to heat, light and motional pressure, but in more complex ways than a rock. Animals in turn have a responsive range beyond that of plants. Finally man possesses a great variety of input, processing and output mechanisms, and apparently this is coupled to an internal reflexive capacity.
posted by No Robots at 8:55 AM on August 21, 2017
posted by No Robots at 8:55 AM on August 21, 2017
News of sentient plants, just days before a significant and highly visible astronomical event? Are we in a John Wyndham novel?
posted by Clandestine Outlawry at 11:27 AM on August 21, 2017 [2 favorites]
posted by Clandestine Outlawry at 11:27 AM on August 21, 2017 [2 favorites]
This thread reminds me of an arts festival I went to in Italy recently, which included 'Club Ecosex' - an environment that was like a nightclub chillout room, except hosted by artists who view sexual encounters with the earth and with plant life as part of their personal mission for a more balanced and peaceful environmental future. It was very weird. I was given a finger condom and invited to stroke an orchid, and then a guy gave me a hand massage with a load of mud. If anything this thread makes me wonder how consenting the plants were.
posted by churlishmeg at 3:49 AM on August 22, 2017 [4 favorites]
posted by churlishmeg at 3:49 AM on August 22, 2017 [4 favorites]
Human sentience can also be explained purely by the mechanics of physics. It might not be all that either. Human species evolve behaviors that entail survival including altruism that increases the survival of the species overall even if it happens to occasionally help other species.
We might also be nothing more than complex processes of molecules obeying the forces of physics in very predictable ways, just, like weather phenomena, at levels that involve enough variables that there is enough randomness in billions of variables thrown in to make it appear that we have "will" or "free choice".
Most of the explanations for plant behavior that prove it unlikely plants could be sensing and feeling could also be used to explain away the probability that humans are sensing and feeling. Ultimately we simply know we sense and feel and apply that innate knowledge onto other beings who behave like us... essentially we give them the benefit of the doubt.
posted by xarnop at 6:04 AM on August 22, 2017 [2 favorites]
We might also be nothing more than complex processes of molecules obeying the forces of physics in very predictable ways, just, like weather phenomena, at levels that involve enough variables that there is enough randomness in billions of variables thrown in to make it appear that we have "will" or "free choice".
Most of the explanations for plant behavior that prove it unlikely plants could be sensing and feeling could also be used to explain away the probability that humans are sensing and feeling. Ultimately we simply know we sense and feel and apply that innate knowledge onto other beings who behave like us... essentially we give them the benefit of the doubt.
posted by xarnop at 6:04 AM on August 22, 2017 [2 favorites]
Than you stonkle, an amazing post, one I'll save as a resource. I'm constantly trying to get clients to see that by protecting soil that their soil can work for them. I once saw a pine tree stump where the bark had continued to grow from links with surrounding trees, this may have been root-grafting but was almost certainly mycorrhiza-mediated.
Maybe not sentience, but sick trees exporting their nutrients via mycorhizza networks certainly appears altruistic. But who are we to say? We're a bag of fungi, bacteria, viruses, MLO's, all of which may drive our psychology, physiology and perception - so how sentient are we? A human without there is a corpse - we can't live without 'em.
Rising CO2 appears to be altering mycorrhizal growth (generally with negative consequences for us). "Ectomycorrhizas and climate change" by Pickles explores this in some depth et al. file is a pdf from U British Columbia.
A novel I can't remember name of had a character visit a planet where the entire surface was a sentient mycorrhizal-superorganism. Humans could not tolerate the place - that's all I can recall.
posted by unearthed at 5:56 PM on August 22, 2017 [1 favorite]
Maybe not sentience, but sick trees exporting their nutrients via mycorhizza networks certainly appears altruistic. But who are we to say? We're a bag of fungi, bacteria, viruses, MLO's, all of which may drive our psychology, physiology and perception - so how sentient are we? A human without there is a corpse - we can't live without 'em.
Rising CO2 appears to be altering mycorrhizal growth (generally with negative consequences for us). "Ectomycorrhizas and climate change" by Pickles explores this in some depth et al. file is a pdf from U British Columbia.
A novel I can't remember name of had a character visit a planet where the entire surface was a sentient mycorrhizal-superorganism. Humans could not tolerate the place - that's all I can recall.
posted by unearthed at 5:56 PM on August 22, 2017 [1 favorite]
I'm a little puzzled, honestly, about why so many MeFites seem happy to make that jump based on what I feel is badly-framed science journalism, or why the science journalists can't let the discovery of the networks be remarkable and interesting all on its own without anthropomorphizing. It's not that plants couldn't have altruism, etc.; it's that there are a lot of possible explanations that explain the observed facts just fine without resorting to so plants are just like people OMG. (The leap to fill in any gaps in understanding of how the process works with "therefore sentience!" reminds me more than a little of the creationist tendency to fill in gaps with "therefore God!") I mean, if sharing resources through a complex interconnected network and communicating with other species in a mutually-beneficial relationship is enough evidence to show sentience, then traffic lights are sentient.
Because, then everything is not all just random and cruel and we can find unexpected kindness where we don't expect it?
That's my story and I am sticking to it.
posted by Samizdata at 2:00 AM on August 23, 2017
Because, then everything is not all just random and cruel and we can find unexpected kindness where we don't expect it?
That's my story and I am sticking to it.
posted by Samizdata at 2:00 AM on August 23, 2017
I finally found the killed tree with bark still growing, this had probably been 'growing ' for about 3 to 5 years.
I agree totally samizdata - for me Marie-Jo Lafontaine's installation 'We have art so that we do not perish by truth' sums it up.
insert sentience, belief, fun, life ... for 'art'.
posted by unearthed at 11:30 PM on August 23, 2017
I agree totally samizdata - for me Marie-Jo Lafontaine's installation 'We have art so that we do not perish by truth' sums it up.
insert sentience, belief, fun, life ... for 'art'.
posted by unearthed at 11:30 PM on August 23, 2017
Terms like intelligence and sentience are grossly overloaded. Even the term "cognition" has long resisted any agreed definition. Here is a recent philosophy paper by Mikio Akagi that argues that such instability in the discussion is essential:
Given these benefits, I recommend an alternative criterion of success, ecumenical extensional adequacy, on which the aim is to describe the variation in expert judgments rather than to correct this variation by taking sides in sectarian disputes. I argue that if we had an ecumenical solution to the problem of cognition, we would have achieved much of what we should want from a “mark of the cognitive”.
posted by stonepharisee at 4:44 AM on August 24, 2017 [2 favorites]
Given these benefits, I recommend an alternative criterion of success, ecumenical extensional adequacy, on which the aim is to describe the variation in expert judgments rather than to correct this variation by taking sides in sectarian disputes. I argue that if we had an ecumenical solution to the problem of cognition, we would have achieved much of what we should want from a “mark of the cognitive”.
posted by stonepharisee at 4:44 AM on August 24, 2017 [2 favorites]
It's excessively anthropocentric to define cognition, sentience or thought exclusively by how closely it resembles our own.
saysthis already referenced Blindsight, and I feel that's a great (fictional) illustration of the idea that intelligence is not necessarily humanlike.
Varela and Maturana in part define cognition as the construction of meaning. I wonder what sort of meaning a millions of years old tree-fungus system has been able to attach to the world?
posted by signal at 5:04 AM on August 25, 2017
saysthis already referenced Blindsight, and I feel that's a great (fictional) illustration of the idea that intelligence is not necessarily humanlike.
Varela and Maturana in part define cognition as the construction of meaning. I wonder what sort of meaning a millions of years old tree-fungus system has been able to attach to the world?
posted by signal at 5:04 AM on August 25, 2017
unearthed: "A novel I can't remember name of had a character visit a planet where the entire surface was a sentient mycorrhizal-superorganism. Humans could not tolerate the place - that's all I can recall.
"
It might be Ursula K. Le Guin's 'Vaster Than Empires and More Slow'.
posted by signal at 6:59 AM on August 25, 2017
"
It might be Ursula K. Le Guin's 'Vaster Than Empires and More Slow'.
posted by signal at 6:59 AM on August 25, 2017
Is an unconscious human sentient? If so, are trees or some sort of trees-and-mycorrhizae gestalt organisms sentient in the same fashion? Will the dreamless gods one day awaken and devour the Sun? Perhaps.
posted by XMLicious at 6:58 AM on September 6, 2017
posted by XMLicious at 6:58 AM on September 6, 2017
XMLicious, the Cabal would like a word.
posted by Johnny Wallflower at 9:19 AM on September 6, 2017
posted by Johnny Wallflower at 9:19 AM on September 6, 2017
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posted by Johnny Wallflower at 1:23 PM on August 19, 2017 [3 favorites]