Hmm, interesting, this reminds me of recent research where they used electrical currents and magnetic fields to enhance tomato plants, I wonder how the two findings are linked. (here's the article I saw: http://horticulturejournal.usamv.ro/index.php/scientific-pap... )
I also remember news about chinese greenhouses experimenting with similar stuff, reporting good growth and much reduced need for pesti-/fungi-/whatever -zides, or none at all in the timeframe of the last 2 to 3 years.
It all resulted from research at Ciba-Geigy AG, Basel, Swiss now Novartis by Guido Ebner, thus also called "Ebner Effect".
Classic conspiracy material, because not usable for a company like that, so they stopped the research, and locked it away. (allegedly)
The researcher died meanwhile, but his sons have some patents, also selling this [2] https://fios-greenbox.net/
Caterpillars don't move the seeds around in a beneficial way. Maybe it can tell the difference? I'm kind of curious what a tomato plant does with the information that it's being munched on though.
> the authors measured the biochemical responses, such as defensive chemicals like hydrogen peroxide, across other parts of the plant. This showed that these defenses were triggered even in parts of the plant that were far away from the damage caused by the caterpillars.
Presumably hydrogen peroxide does not taste good to caterpillars.
That's a fun idea. Although over time this might select for plants that complain more. You could end up with an entire garden screaming for attention all the time.
Or you’d just be evolving the plants toward communicating more clearly, ala cat meows (which don’t exist in adult cats for any other reason than to allow communication with humans.)
I believe the hypothesis is that they evolved as a "thing domestic cats can do" for communication with humans, but adult cats that know how to meow, don't just use their meows to communicate with humans. They see it as a general communication tool, and will also try to use it with other cats.
The supporting evidence for this hypothesis, I believe, is that meowing has been observed to be a learned communication technique gained only if a cat interacts with humans during development; adult feral cats, living only around other cats during their development, never learn this technique or its social meaning, and so don't understand the social signal being communicated by domestic cats when the domestic cat meows at them, nor do they try to use it in response.
(Same goes with the domestic cat's social signal of keeping their tail raised when standing to express trust. Feral cats don't develop that habit, either.)
Plants have all sorts of defense mechanisms, toxins etc, that they've evolved (since they're sitting ducks). Its a reasonable hypothesis that some energetically intensive to produce toxin could have its production induced, for example (the plant wouldn't want to waste energy on producing the toxins when not needed). I believe there are also plants that have been shown to release compounds that attract parasitic wasps to kill the pest. That could also be triggered here, another reasonable hypothesis.
I wanted to share the Hidden life Of Trees book, for anyone finding the above fascinating. The author explores the idea that trees use fungal networks to communicate, which is further to what we see about the plants here.
Plants can do amazing things. Think about how our own bodies respond to extreme temperature or to shock. We withdraw vital fluids to the core, or bring certain resources to the site of irritation. Plants certainly do things like this.
The research paper's abstract says this:
>The results show with 90% of accuracy that the electrome registered in the fruit's peduncle before herbivory is different from the electrome during predation on the fruits. Interestingly, there was also a sharp difference in the electrome of the green and ripe fruits' peduncles before, but not during, the herbivory, which demonstrates that the signals generated by the herbivory stand over the others. Biochemical analysis showed that herbivory in the fruit triggered an oxidative response in other parts of the plant.
e: side note, this is the software they used for the computation, including Machine Learning.
>The code libraries used were: Numpy and Pandas for data manipulation; Scipy, Obspy and Math for mathematical calculations; Matplotlib for creating graphics; Sklearn and Statsmodels for machine learning.
I'm not sure if this paper is talking about the same thing but it discusses the effect of
reactive oxides and antioxident balances in plants and their effects.
> In addition, the authors measured the biochemical responses, such as defensive chemicals like hydrogen peroxide, across other parts of the plant. This showed that these defenses were triggered even in parts of the plant that were far away from the damage caused by the caterpillars.
Perhaps it’s just a side effect of some other system in the plant, like an electrical pulse to communicate “the way this branch is growing has little/much sunlight”.
That's a 'phototropism' IIRC and it's not caused by electrical signals but instead by growth hormones called auxins. This is what little I recall from high school biology, anyways. IIRC the auxins inhibit cell division and different ones cause different tropism phenomena.
Probably the latter: Taste bad, and possibly become more poisonous for catepilars. It is quite possible to use that electric signal to trigger some chemical reaction that would accomplish this.
The article mentions releasing hydrogen peroxide. Not just in the one fruit being attacked but the other fruit on the plant also released more chemicals.
If you assume the human-centric definition of the word "pain", perhaps. But I don't think that paints a complete picture - organisms experience and react to negative stimuli in so many different ways.
IMO, what we're seeing here could absolutely be considered "pain" in the plant kingdom, without altering or stretching the definition of the word even in the slightest.
Why would you use a human term like pain for the plant?
Here's a biologist saying not all humans experience pain, if it's not even a universal human experience I don't know why you'd apply it to plants instead of a more technical term:
"Interviewer: Right, and isn't sensing damage, even without a neural system, essentially pain?
Daniel Chamovitz: The idea that damage has to be pain is mistaken. We feel pain because we have specific types of receptors called nociceptors which are programmed to respond to pain, not to touch. People can have genetic malfunctions where they feel pressure but never feel pain because they don't have pain receptors."
A different article on the subject on plant pain has a biologist suggesting not to use human terms or animal terms:
""Plants can detect light, but I don’t think you can say plants can ‘see.’” The same goes for hearing, tasting, feeling, smelling. The terms we use to describe our own interface with the world don’t seem transferable to plants. They describe the contours of a human-centric reality, made possible by our animal anatomy.""
without altering or stretching the definition of the word even in the slightest.
The word "pain" has the concept of the mental experience of suffering pretty much baked in to it. Applying it to plants seems to very much stretch the definition when there is literally no biological structure in plants that corresponds to the neural activity organisms with a CNS when experiencing pain. An electrical pulse isn't really sufficient: plants send electric signals under a variety of circumstances.
Pain isn't merely a response to negative stimuli. That does stretch the definition.
Not sure whether it's centralised, but the finding of the study in the article sounds like it's essentially that plants (or at least this type of tomato plant) do have some form of nervous system or equivalent, isn't it?
Reacting to a stimulus doesn’t necessitate the need to feel pain. A computer doesn’t feel pain when I plug in a USB drive, but it certainly sends an electrical signal to let other parts of the computer know something happened.
This research doesn’t suggest that plants suffer or are somehow sentient, just that they react to stimuli in a way that’s advantageous to survival.
There's also no evidence that plants (or computers) don't feel pain. We really have very little knowledge of what does or does not cause conscious experience.
We also don’t know if rocks feel pain, but it’s a safe assumption since we don’t see them attempt to avoid being destroyed.
If you try to cut an animal, it runs away or fights back. If you try to cut a plant, it sits there are lets you cut it. A plant may have some electrochemical response to ensure that a predator doesn’t kill it (which could simply be the result of natural selection), but that isn’t good evidence for us to even begin to entertain the idea that a plant feels pain.
In the absence of evidence, we shouldn’t make up wild ideas that don’t fit our best current understanding.
Spend some time looking at sped up videos of plants and then state that same feeling about their lack of reactivity with the same feeling of absolute certainty.
Some species have been shown to communicate using pheromones to increase tannins in the leaves of their neighbours.
Agreed about in the absence of evidence, but in the absence of much study being done we could maybe have a closer look?
I don't think you can separate "feel" from the concept of pain. That's pretty much baked in. Maybe there just needs to be another word to encompass plant signalling of this sort.
I am not sure how this is perceived as attack ? Sending electrical signals doesn't have to mean attack by default. Pollination happens via bees.. then the fruit grows to attract birds or animals who eat them and spread the seeds through excretions or else the fruit will fall off and rot...
The plant world is "smarter" than we give it credit. Some plants count, keep time, and communicate with their environment. This research is in a similar vein to this TED talk showing some of the neat things plant do that we would attribute as features of the animal kingdom.
My father grew up on a farm that was mostly for subsistence. He said to pinch off the first few green tomatoes to improve yields. I occasionally do this but have not tried to measure any yield differences.
That's simple pruning; the plant can be encouraged to grow more foliage before it turns its attention to making fruits; thus making more plant mass available to do the fruit growing.
In my experience that tends to encourage more, smaller fruit; which is good cuz it reduces loss to insects etc (they ruin a whole fruit at a time). If you want a single tomato the size of a child's head, tho; let it keep the first few it sets and then pinch flowers before they open after that.
This process is called "thinning" [0] (as distinct from pruning), and is employed by farmers the world over. And has been done for several hundred years.
There were 4 tomato plants in the experimental group and 1 in the control group (so 5 in all).
I don't think we can declare that plants think or even have communication among their parts based on this small amount of data. Too many other possibilities.
> Plants have a multitude of chemical and hormonal signaling pathways, which are generally transmitted through the sap
That's why I find popular claims of the form "plants can't do X because they have no nervous system" somewhat misleading. Plant cells still have all the other means of inter-cell signalling available - so communication and information processing is happening a lot slower in plants than in animals, but it absolutely does take place.
So maybe it makes sense to speak with your plants ; )
Anyway don't find it that surprising. Basically it seems a natural advantage to have such warning mechanism.
I do a veg garden, with tomatoes of course. When I water them at the end of the day I also spray the tops because I want the leaves to tell the roots...get ready, rain is coming.
I have no idea if this happens or not. But from a survival perspective it makes sense that it would.
“A green salad?” said the animal, rolling his eyes disapprovingly at Arthur.
“Are you going to tell me,” said Arthur, “that I shouldn’t have green salad?”
“Well,” said the animal, “I know many vegetables that are very clear on that point. Which is why it was eventually decided to cut through the whole tangled problem and breed an animal that actually wanted to be eaten and was capable of saying so clearly and distinctly. And here I am.”
- Douglas Adams, The Restaurant at the End of the Universe
The only morally sound answer to that question is "anything or nothing" because any other choice implies that you have to justify why one organism is more worthy of life than another. Am I wrong or just not fun at parties? :D
That's pretty much the only way I eat animals. It may be anecdotal, but supermarkets near me sell all of their meat pre-killed in neat little packages. I've never had to grind the beef off of a live cow to get my burger meat. Lobsters are an exception to that rule, but still generally seem dead by the time people eat them.
My point was that there is no list that anyone can make that lets you sidestep the unpleasant fact that you have to kill something to eat (each of your 5 points involve taking the life of something else. Even eating roadkill implies killing bacteria and parasites). On top of that, you'll never know if the thing you killed felt pain so any choice you make is ultimately arbitrary. I'm not saying I feel good about this bleak conclusion but I'd rather be honest about it. My dinner deserves to know that it wasn't an easy choice!
My dinner deserves to know that it wasn't an easy choice
I hope my dinner knows how delicious it is before I eat it. I would tell it if I could. Although that could get pretty awkward if it's something I don't like much:
"Listen, can we just agree that neither of us is really going to like what is about to happen?"
> Plants don't have a central nervous system or a brain. What science generally understands under pain and suffering plants simply don't have.
Quite a number actually do have nervous systems [0], using neurotransmitters that have actually been found in mammals. They respond to wounding, both with efforts to repair it, and with chemical deterrents to the cause.
Now, that isn't to say that they necessarily have pain and suffering, but it wouldn't be surprising to learn that some plants possess that capability.
I have no idea where the ethical line ought to be here, but if plants have meaningful capacity to suffer then it’s also likely that PETA should be campaigning to limit the mistreatment of even the tiny AI we make while doing MOOCs on the basics of machine learning.
>Plants don't have a central nervous system or a brain.
So? does that automatically imply that it does not feel pain?
>What science generally understands under pain and suffering plants simply don't have.
Listen, I don't buy the science say this and science say that kind of arguments. ANY living being ( assuming we can settle for what can be called 'alive') will have a mechanism for self preservation, pain is one of them. The onus is on 'science' or people to prove otherwise.
If we think about the function of pain from an evolutionary perspective its basically to encourage, well, not doing whatever is causing you pain (e.g. touching sharp objects, standing close to a fire) or provide motivation to fight or flee (e.g. if I am being attacked by a bobcat).
Neither of these are applicable to plants, so there doesn't seem to be any evolutionary reason to evolve pain receptors.
Assuming that I did not misunderstand you, while fight or flee does not exist in plants in the same sense as animals they do react by producing chemicals/sap etc. that works as a defense. So it's more 'fight', but a chemical warfare at that.
Pain is a subjective experience. It requires a self to feel it.
No central nervous system does imply no mind to feel pain.
If you were to scoop my brain out of my body and keep my lower body alive below the neck the nervous system would not feel pain as there is no mind to feel it.
How do you know that? Science has no idea how the brain produces consciousness (and therefore strong basis to claim that other entities don't). There might be all sorts of selves that you simply can't observe.
We don't know how the brain produces consciousness but we have a good idea from observing people suffering brain damage from accidents how a functional brain is directly linked to consciousness.
Science can't prove the world is not the dream of a giant turtle- so technically I can't "know" anything- so asking "how can you know that?" Is kind of a boring line of questioning. It has no answer other than "Well I guess technically I can't know that, or anything," But that doesn't mean turtle dreams are going to get equal weight with our empirical models of the world.
There might be all sorts of selves that you simply can't observe.
Or there could be none besides those with a CNS. Science may have a long way to go on understanding minds, but speculation on other sorts of minds entirely is still within the realm of science fiction. So, if you're going to assert something like a conscious experience by plants then you should understand that you are taking it as an article of faith.
But science has no way to observe consciousness even in those entities with central nervous systems, not even humans. The inference of consciousness is entirely based on observed behaviours being similar. I'm not asserting that plants have consciousness. But I am suggesting that we ought not to completely dismiss the idea.
Thanks for clarifying. But I would take issue with the statement "science has no way to observe consciousness"
A cornerstone of science is empirical observation, and we can all observe our own consciousness to some degree. It's hardly perfect or even nearly complete, but it's something.
The onus is never on other scientists to prove an assertion false if it is made without evidence. The initial burden is always on the person making the initial claim.
You can play semantics with the word "pain" all you want, but the biological differences between what we call pain as experienced by humans and the stimuli response from plants are sufficiently different to surpass a difference of degree and make it a difference of kind. You need a word besides "pain", or the onus is on you to demonstrate the appropriateness of that term when you are using it so far outside its normal context.
Unlikely, unless the fruit is raw. Some ripe fruits are most likely meant to be eaten because that's the mechanism that plants have evolved to disperse seeds, so it would actually be "rewarding" for the plant. Perhaps it would be similar to a little orgasm. Now a raw fruit will most likely feel pain.
This isn't entirely new. L. Ron Hubbard ran experiments like this in the 60's and came to similar conclusions. He found that “tomatoes scream when sliced.” Check this article a bit over halfway down the piece: https://www.bostonglobe.com/ideas/2012/06/16/meet-your-veget...
No, but it is certainly funny seeing this on the front page of HN after laughing on and off over a period of literal years about the L. Ron 'Tomatometer'...
