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The idea that plants even can be talked about as being conscious. How do I get my head around this? They don't have brains for a start. So? So there's a disadvantage. Where does the consciousness come from? Well, one of the interesting things is that you can get neuronal behaviors without neurons. And this has been demonstrated by a biologist I interviewed named Michael Levin. But in the case of plants, there is this group of botanists and I should say they're not mainstream. They're a little to the side, but they're doing really interesting experiments on plants to demonstrate that they have intelligence and possibly conscience, consciousness or sentience.
Just a couple examples. At random, plants can see what yes, we know they can tell the difference between light and shade. But even more than that, there are vines that can change their leaf form to mimic the leaf of the plant they're twining up. So how do they see that leaf form? How do they change themselves? Their plans? They can hear you play the sound of a caterpillar chomping on a leaf, and they will release toxins to those leaves to protect themselves. Where? Of something like caterpillar being nearby. Yeah, yeah. And they also can hear the sound of water in a pipe. And roots will seek that. That's fascinating.
It totally is. And they, they may have a form of echolocation like a bat. If you have a bean plant climbing, looking for a pole. You know, we've all seen this in our gardens. You know, they do this circular motion, the spiral. Darwin called it circum nutation. if you look at a video, a time lapse of that, the bean plant knows exactly where the pole is long before it touches it. So how does it know where it is? And you see that it's kind of casting itself like a fly fisherman toward the pole, straining to get there. And then when it gets there, you can see it kind of relax its leaves or relax.
It may be that it's bouncing. So every time a plant cell divides as it grows, it does emit a little sound. And it may be that they can reflect that sound off of a pole and figure out where they are. Perhaps the spookiest thing I learned was that plants can be put out by the same anesthetics that put us out for surgery. Now, aren't they out all the time? No, they're just slow. They have behaviors. We exist in a different frame. someone's experimented this. Oh, yeah? Yeah. And so you can take a Venus flytrap, a plant with an obvious behavior,
and you can, you know, put it in a bell jar with some xenon gas or one of these anesthetic chemicals that we use, and it will not respond when apply when a fly crosses its threshold. So you have to ask yourself, what has the plant lost when it goes under anesthetic? We would say we've lost consciousness. And some of these scientists say, well, this applies if you have two states of being, one of them being conscious and one not. I don't think the word consciousness is right for plants just because we have associations of a fully developed self, of self-consciousness, of, you know, we're not just aware.
We're aware that we're aware. And that's a level that plants don't have interiority. I don't think so. This is going back to what you were saying earlier. Sentience. Yes. That's why it's more comfortable with that word. Plants have a kind of sentience. It sounds like they have a form of intelligence, a body without some sort. That makes for me listening to all of this. All of it is kind of mind blowing. But the idea that plants would have intelligence, you know, not in this sort of human cognitive intelligence thinking and reasoning, but just intelligence in the sense that they are they have to solve problems.
Exactly. They have to go towards light. They have to find nutrients, calling that intelligence doesn't seem too much of a stretch to me, but sentient makes them seem a bit more living. I mean, they of course are living, but there's something more to the more purposeful, I guess. Yeah, purposeful. Well, you know, we used to just say everything was instinct, right? Everything's programed in chemistry, in your DNA. And, and the point of that this kind of biology is getting at is that the environment is so changeable that you can't program every, every eventuality, every contingency. And so that what nature, what evolution
creates are problem solving creatures in different niches. And they need the tools to respond to unexpected changes in the environment. And that's that's part of what's happening. Another experiment that demonstrates this is you can teach a plant, you can condition it, give it a lesson, and it will remember it for 28 days. And they do this with a plan called mimosa pudica or the sensitive plant. This is a tropical plant. When you touch it looks like a fern. When you touch it, all its leaves go, you know, dead. It's like playing possum so it won't get eaten. if you shake the container, you have a mimosa.
And initially it will, it will think it's being touched and will react. If you do it enough times, it'll learn. Oh that's funny. I don't have to worry about that. And then for another month it'll remember that. So it's it's how is it storing that information. That's what I want to know. Now that's see, that's a really interesting question because we think you need neurons to store information. But what has been discovered recently is that there are these bioelectric fields. There's a scientist I interviewed several times named Michael Levin at Tufts, and he's really made a specialty of this and that.
Whenever you have a multicellular organism, what holds it together are these fields of electricity. And we only we knew about that. There were these fields from the 30s, but it was only when we invented these voltage sensitive dyes that we could see what they're doing. And these dyes react. They change color depending on how much voltage they're receiving. And you put this on a, you know, you grow cells out in a petri dish and you put this on it and you see there's a lot of action going on. So what Levin did was he works with planarian,
which is a worm, a little worm that can regenerate any missing body part. He's very interested in regenerative medicine and how that works. And he teaches the area a simple lesson. You can condition them. Then he chops off their head, they regrow their head and they have. The lesson has been retained. So the lesson was held in the body, not in the brain, not in the brain. And so bioelectric fields can hold information. And that probably explains what's going on in the plants because they have these fields. So, you know, he would say neurons are over overrated, that you can get neuronal behavior from any cell.
It's just slower. Well, I guess that sort of speaks to the idea that if information processing or computation is one of the sort of fundamental sort of things that life does, we are familiar with it from human points of view, and also in the artificial computation that we've created in computing physical computers and things. But when we do it through neurons and, and biological cells, but there's no reason why other bits of biology, other forms of biology wouldn't be able to do computation in their own way, which we don't recognize. And if we're not looking for it, we'll never find it. That's right. And we're so fixed on you do it with neurons.
Yeah. And you know, that's one way to do it since we're talking about plants having sentience and potentially going towards the direction of consciousness, which is already kind of two steps in the direction of me sort of having to sit down and think about it hard. Can I ask, can I keep pushing if this is the case that we're understanding with plants, does that mean that plants could have feelings desires? So whenever I start talking about this, people start wondering if you didn't say no glands. The question that occurred to me is, do they feel pain? Because that's troubling. And is the scent of jasmine actually the scream of a plant that's being abused?
I talked to two different plant neurobiologist about this and one said, said, yes, of course they feel pain, but we have to eat them. And then I asked someone else who said no pain would not be adaptive for a creature that can't move. And that pain is very useful when you can take your hand off the stove or run away from the source of pain. But since plants can't do this, they're aware they're being eaten, but it doesn't hurt them. That was reassuring because presumably creature that feels pain. Ever since Bentham we've said, you know, they deserve moral consideration. And what would be left to eat, you know, salt.
I mean, well, well, well, also plants require being eaten to, to spread their seeds. Right. For in many cases that's. Yes, they produce seeds and fruits. For that reason they would be very want us to eat those and also grasses. And that's a big base of our diet right. You know, grain, rice and wheat grasses are regenerated by being eaten. They co-evolved with the ruminants that eat them. So don't worry. Your most famous phrase can stay. In that case, stay in place, you know, eat food. Not too much. Mostly place, mostly plants. Yeah, exactly. With a clear conscience.
