Chapter 6: The Plant Body Keeps the Score

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Okay, let's unpack this.

So for this deep dive, I want you to start by picturing something.

Imagine it's an unseasonably warm day in a city like Berlin.

It's late September.

Right.

And if you've ever lived through one of those long dark winters, you know that feeling.

There's this frantic rush to soak up the last bit of sun before the gray months really settle in.

Absolutely.

You see people everywhere just tilted upward in parks, eyes closed.

Exactly.

Like they're trying to record the sensation of warmth and light.

And that primal quest for light, that instinct to record a sensation before it's gone is actually a perfect biological metaphor for what we're talking about today.

Right.

Because we are diving into the concept of memory.

We are.

But we're looking way beyond the centralized brain.

We're exploring this, well,

this revolutionary idea that the plant body keeps the score.

Keeps the score.

Yeah.

It's recording everything.

Time intervals, touch, how cold it's been, even nutrient density.

And then it uses that stored information to make these

really adaptive future oriented decisions.

The sources we've gathered for this really center on a pretty profound idea.

Plant memory.

Specifically what's called individual elastic memory.

And that's a key distinction.

This isn't just the rigid genetic blueprint that says a leaf should be a certain shape.

This is information storage that actively changes when the world around it changes.

It's really the basis of learning of adaptation.

And if plants can do it, it completely reframes how we understand complex behavior and intelligence across, well, the whole tree of life.

I mean, memory is the basis of everything, right?

Whether it's neural or not.

It's how you orient yourself in time and space.

It's the ability to look at the future based on the past.

Exactly.

You're not just reacting to the now.

So our mission here is to understand how an organism that doesn't have a nervous system can record and recall information and what that implies for what we call consciousness or intelligence.

And the moment that really hooks us into this whole conversation is an observation about this high altitude plant.

It's called Nessa poissoniana.

A flower that just baffled botanists.

Right.

And when a researcher, Tilo Henning, was asked about its behavior, the question he got was so simple, so immediate.

It was just, what do you mean the flower remembers?

And that's where we have to begin.

What does it mean for a flower to remember?

So let's start with this memory flower.

Where do we even find it?

Well, to really get it, you have to appreciate the environment it lives in.

We're starting high up in the Andes, but we're really following the journey of two researchers, Tilo Henning and Max Wigand.

And they've had, what, a decades -long obsession with this one plant family?

The loessaceae family, yeah.

That's the group that Nessa poissoniana belongs to.

And this family is known for two things.

On one hand, these incredibly elaborate, almost alien -looking flowers.

Designed for really intricate pollination.

But on the other hand, they have these incredibly painful, well -calibrated, stinging hairs.

It's a and Wigand in particular was just fascinated by their defenses.

The source material gives us a pretty striking detail about that.

These aren't just, you know, annoying little prickers.

No, not at all.

They are highly evolved biological weapons.

They use the same chemical ingredients, things like calcium oxalate and silica that we use to build teeth and bone.

That's incredible.

They're literally built with materials designed for hardness, for longevity.

Because stinging is tough work.

The hairs are built like these tiny microscopic hypodermic syringes.

And they have to be hard enough to pierce through, what, the exoskeletons of their predators?

Precisely.

They're calibrated with different mineral combinations to match the exact hardness needed to pierce the skin or the ketene of whatever animal is trying to eat them in that specific ecosystem.

That level of chemical investment, that specific architecture, it points to a very long, very refined evolutionary arms race.

It does.

But what's so interesting is that it wasn't the defense strategy that clued them into the plant's intelligence.

No, it was an experiment inspired by just watching bees.

Watching bumblebees in a greenhouse in Bonn, Germany.

And that's when Henning and Wigand realized these plants weren't just reacting to threats.

They were actively predicting the arrival of their allies, their pollinators.

This is where it gets really This is the core of it.

They discovered that Nasa Poisoniata could store and recall the time interval between bee visits.

It's keeping track of time.

Yes.

And based on that stored chronological information,

the flower strategically presents its pollen only when it expects the next pollinator to show up.

It's planning its behavior around future events that it predicts based on past data.

It's easy to see why it got the nickname the flower that behaves like an animal.

It really is.

But to fully appreciate this memory, you have to look at its whole pollination strategy.

It's like this complex risk management and accounting system.

And the pressure to get it right is immense, right?

Given where it lives.

The ecological pressure is enormous.

These flowers are thriving in these harsh high elevation conditions.

We're talking one to three miles above sea level.

Wow.

And they often survive in these tiny isolated populations.

So if a flower misses a pollination opportunity,

it might miss the only opportunity for days, maybe even weeks.

Every single interaction has to count.

Everyone.

And that's why Nasa Poisoniata is a master of what you could call pollen rationing.

It parcels it out carefully.

It only displays a small portion at a time.

And the evolutionary reason for that is pretty clear.

It's maximizing genetic diversity.

Exactly.

It makes sure that no single bee gets the entire pollen jackpot.

It forces the pollinator to visit multiple flowers, hopefully spreading its genes far and wide.

And this accounting system gets even more sophisticated, doesn't it?

It can adapt to changing conditions.

It does.

When the plant senses that there are fewer pollinators around,

maybe through a lack of recent visits, it immediately switches strategies.

It hedges its bets.

So instead of rationing out tiny amounts, it offers up these larger globs of sticky, cohesive pollen.

It's maximizing its chance of success when the opportunities are few and far between.

And the way it manipulates the pollinator is just, it's incredibly shrewd.

The flower actually dilutes its own nectar.

Right.

Which sounds counterintuitive.

Why would you water down the reward?

But there's a reason.

There is.

It trumps the pollinator to return twice to get the same amount of sugar it would normally get in one visit.

A double visit.

By demanding a double visit, the flower ensures the bee's body gets dusted with pollen both times.

Once on the first visit and again on the second.

It doubles the potential for a successful gene transfer.

This is not a passive vending machine.

This is an active strategy.

It's an active strategy to maximize its reproductive output in a place where resources are scarce.

Okay.

So let's get into the mechanics of this.

How does the plant actually move?

Well, this is another remarkable thing about the place, Soniana.

It's one of the very few plants where you can actually see the movement with your own eyes.

You don't need a time -lapse camera.

That's festery talking.

Its stamens, the pollen -bearing parts,

move from a horizontal tucked in position to an erect vertical one in just two or three minutes.

You can actually watch it happen.

You can.

And the flower's complex structure is what dictates the trigger.

The stamens start lying down, hidden inside these concave petals.

And then the bee arrives.

Right.

And when the bee lifts a central scallop -shaped petal to get to the nectar, that mechanical action somehow triggers one of the stamens to stand up and deploy its little parcel of pollen.

Do we know how that works?

The immediate mechanism?

The exact mechanism is still unknown, but we could make some educated guesses based on other fast moving plants.

Like the Venus flytrap snapping shut.

Or the white mulberry, which catapults his pollen at half the speed of sound.

In those cases, the movement is driven by rapid hydrostatic changes.

The changes in fluid pressure.

Exactly.

Fluid pressure building up or releasing very quickly, often kicked off by an instantaneous ion flux across cell membranes.

And the movement of Nasa Pleisoniana is clearly controlled and purposeful.

It's not just a random twitch.

Not at all.

It rises to a perfect, aerostrate 90 degrees to form a cone shape.

And that led the researchers to the crucial hypothesis.

Which was?

If the plant is expending all this energy to move its reproductive parts, it must be optimizing that effort based on its previous interactions.

So they started asking, maybe they recognize how often pollinators come and only move when it's actually worth the effort.

And that question led to the 2019 discovery that confirmed this time interval memory.

It did.

And they'd already observed something they called the genetic fake out.

Okay, what's the fake out?

So once a bee drains the nectar, the next bee that comes along finds no reward.

But the flower, understanding how important gene transfer is, will still raise a new stamen full of fresh pollen.

So it dusts the disappointed bee anyway?

It dusts the departing disappointed bee regardless.

And the logic behind that is just brilliant risk management.

It is.

Especially for these isolated populations.

An insect that finds no nectar isn't going to linger.

It's not going to try another flower on the same plant.

It's going to fly farther away.

Much farther away.

To a neighboring, genetically distinct plant, carrying the pollen from the empty flower with it to a distant recipient.

So it actively promotes cross pollination.

It avoids inbreeding.

Exactly.

But the really shocking part was realizing the stamen would already be raised before the next bee even arrived.

It was anticipating.

It was using past timing to predict the future.

Yes.

And to test that rigorously, Henning and Wiggin took the place of the bees.

They started manually probing the nectar cavities with little tools.

Right.

To isolate the time interval is the only variable?

Precisely.

They set up three different groups of flowers.

And what were the groups?

The first group was probed really frequently, every 15 minutes.

The second group was probed every 45 minutes.

And the third was a control group, just left alone.

And the results the next day?

They were definitive.

Clear -cut proof of memory retrieval.

The 15 minute group energetically raised their stamens on a rapid 15 minute schedule.

And the 45 minute group?

They waited longer.

They raised their stamens further apart,

aligning their behavior perfectly with the interval from the day before.

The plant was clearly adjusting its display timing based on the specific experience it had recorded.

And this is that critical elastic element of the memory you mentioned?

This is it.

They pushed it even further by changing the interval.

So they'd switched the 45 minute group to 90 minutes.

And did the plant adapt?

By the very next day, the Nasa Pleisoniana had adjusted its display timing to line up with the new, longer schedule.

It wasn't following some fixed, rigid code.

It was learning from experience and adapting its future behavior.

This plant wasn't just a masterful pollen accountant.

It was a memory flower.

Okay.

So when you see behavior that I mean, counting time, changing what you're going to do based on what happened before, it just throws you right into this huge debate that's happening in botany right now.

A huge debate.

Does this kind of behavior mean intelligence or even consciousness?

And this is where the language, the terminology gets really sticky.

It does.

Henning and Weigand were very careful at first.

They put the word intelligent in quotation marks in their paper.

To protect themselves, basically.

Right.

Because you're immediately up against this traditional, very anthropocentric argument.

Is the flower just an unconscious machine, a very complex automaton with pre -programmed responses?

Or is it exhibiting something that we have to call intelligence?

And the dissenting papers, the ones that push back, they almost always focus on one single thing.

The lack of a centralized brain.

No brain, no intelligence.

That's the argument.

No neurological center to process and store information.

So there can't be intelligence and certainly no consciousness.

But isn't that a bit of a semantic trap?

I mean, if you look at the process itself, separate from our own anatomy?

I think so.

If the core mechanism is identical, you take in information, you process it, you make a choice, and you perform an adaptive reaction, then arguing about the anatomical structure seems almost beside the point.

So what did Henning say when he was pressed on this?

Well, he eventually dropped his careful reserve and offered this really powerful rebuttal to the whole brain -centric argument.

He just laid it out.

He laid it out.

He said, look, the plant takes information from the outside world, it processes it, it makes decisions, and it performs a reaction.

And he argues, and I think it's a great point, that this to me is the basic definition of intelligence.

I mean, that's not just automatism.

Right, just growing toward the light.

That might be automatism.

But adjusting the timing of your reproductive display based on the specific learned interval of your last visitor.

That's strategic.

That's adaptation based on stored data.

Which naturally leads you to the central mystery.

If this is intelligent, where's the memory stored?

If it's not in a brain, where does NASA Poissoniana keep the record of these time intervals?

And Henning's hypothesis here is really foundational to this whole idea of

distributed consciousness.

It is.

He suggests we might be looking for the wrong kind of thing, a centralized hub that plants just don't have.

He actually says maybe they are so spread all over the body that there isn't a single structure.

Maybe that's their trick.

Maybe it's the whole organism.

The whole organism, remembers?

The whole organism.

And if we accept that idea, we have to broaden our definition of memory way beyond our human narrative sense of self.

Right, because philosophers of mine often make a distinction, don't they, between conscious memory, our long -term stories about who we are and this short -term accounting we see in plants?

They do.

The traditional view would hold that a plant adjusting its stamens isn't participating in anything remotely conscious.

But there's another school of thought.

There is.

Others argue that all memory, the ability to turn a neutral sensory input into a piece of actual, meaningful information, shares a common basis with consciousness, no matter how long it

And if we connect this concept of distributed whole -body memory to the bigger picture, you actually find parallels within our own bodies completely separate from our brains.

We do.

We talk about the body keeping the score.

And it's tangible.

It's real.

Our immune cells remember pathogens.

That's a functional, adaptive memory.

It's not part of my conscious self, but it allows my body to survive a second encounter with a virus.

That is functional, non -neural memory in action.

And then there are the even more profound epigenetic memories.

Right.

These aren't changes to the genetic code itself, but these chemical tags, these markers that sit on top of the DNA.

Like little cellular bookmarks.

That's a great way to put it.

They're cellular bookmarks that control how genes are expressed.

And we're learning that these epigenetic memories can travel down through generations.

As a result of stress, trauma, pollution.

All of it.

And they impact health markers in children and grandchildren.

They are these silent, but very tangible non -neural memories that shape an organism's future.

So the idea of a plant having a cellular distributed memory isn't really so alien then.

Not at all.

It's a mechanism we're only just beginning to understand in ourselves.

We don't really have the words to fit this kind of non -neural memory into our human sense of self.

So maybe we shouldn't demand that plants conform to our anatomical standards to be considered intelligent.

Okay.

So if non -neural memory can be stored in the cells, what happens when a plant has to keep score of something huge, like an entire season?

Right.

This takes us from that high altitude flower down into the cold, dark soil of, say, Connecticut.

And we're talking about the concept of vernalization.

Which is illustrated really well by the simple act of planting garlic.

Perfectly.

You take those smooth milky cloves in the late fall, you put them in the dirt, and by July, they've multiplied into a whole new head of garlic.

But that growth won't happen unless that clove experiences something very specific.

It needs a specific duration and intensity of cold.

It needs the memory of winter.

And this requirement is called vernalization.

Yes.

And it's vital for so many temperate species.

Apples, peaches, tulips, daffodils.

They all need it to trigger flowering and fruiting.

So if you buy bulbs in a warm climate, you have to fake that memory.

You have to put them in the

passage of cold.

And crucially, it has to determine that the warmth that follows is reliable.

Because a plant commits to emerging during a two -day warm spell in February.

It would be a disaster.

The next frost would kill the new shoots.

So the plant has to store this chronological information,

measure duration, and make a really high -stakes survival decision based on that stored memory.

And it's counting at a molecular level.

It is.

The mechanism often involves a key flowering repressor protein called FLC.

This protein's job is to block flowering.

Until it's told not to.

Exactly.

And prolonged exposure to cold, the memory of winter, causes the plant to chemically suppress this FLC protein.

So this molecular switch is basically the plant's internal stopwatch.

It's the stopwatch.

The cold has to be sustained long enough to fully silence that FLC gene.

And once the gene is silenced, the plant retains that cellular memory of winter accomplished.

And then when the real warmth finally arrives.

The FLC stays suppressed, which allows all the other flowering genes to finally activate.

And that memory also informs its decisions about the warmth itself.

The source mentions they wait.

They wait until the warmth is sustained for four days or more.

It's a classic risk assessment.

Four consecutive warm days makes it statistically much less likely to be a temporary fluke.

So it's a worthwhile investment to start growing.

Exactly.

It's complex, quantified memory.

And we see a similar kind of information recording with the Cornish mallow, which has this incredibly elegant photoreceptor memory.

Right.

It records the position of the sun.

Both the position and the intensity.

The mechanism is both predictive and adaptive.

The mallow will turn its leaves hours before sunrise to face the exact spot on the horizon it expects the sun to appear.

How does it do that?

How does it physically move the leaf?

It adjusts the trigger pressure, the water content, in the specialized tissue at the base of the stalk, the pulvinus.

It basically bends the leaf into position.

So all day, its photoreceptors are encoding the amount and direction of sunlight.

It stores that overnight.

And uses it to predict exactly where and when the sun will rise the next day.

It allows for optimal light capture from the very first moment.

And researchers tested this, right?

They simulated a chaotic sun.

They did.

In the lab, they switched the light direction frequently and randomly.

And the mallow learned the new chaotic light patterns.

It adjusted its movement to face wherever the light source was most frequent.

Which got the attention of people working on solar panels.

It did.

The research team called it extraordinarily complex, yet extremely elegant.

And it sparked interest in creating smarter, dynamically adjusting solar panels that could learn and predict like the mallow.

So this continuous demonstration of memory, vernalization, counting, light tracking.

It all reinforces this one fundamental idea.

That memory and learning are not, you know, some peripheral luxury.

They are fundamental evolutionary strategies for survival, deeply embedded in plant biology.

And even though our evolutionary paths diverged so long ago, when we were single -celled organisms.

We still share these fundamental rhythms.

Plants have circadian clocks.

They move through growth cycles.

And they maintain a quantifiable record of their past environmental experience.

At the end of the day, the ability to remember your past experiences is just an incredibly useful tool for survival in any living system.

The most useful tool.

So if, as Henning suggested, plant memory is distributed throughout the whole body, then any purposeful movement we see is the most visible expression of that stored information.

Exactly.

The plant body records the data and the plant moves accordingly.

We see this so vividly in the more specialized rapid responders.

And the Venus flytrap is probably the most famous example of that.

It's a master accountant of touch.

A master accountant.

It has to count interactions to be sure it has caught a living creature before it commits the massive amount of energy required for digestion.

And the counting mechanism is so precise.

The first touch of a trigger hair signals, what, a potential meal?

Potential meal.

The second touch, if it happens within about 20 seconds, signals a moving, living creature.

And that's what causes the trap to snap shut.

So the cellular memory of that first touch is informing the decision on the second.

It is.

The initial response is driven by an electrical action potential, sort of like a nerve impulse, but slower.

But the crucial memory storage is physical.

The impulse triggers a release of calcium ions inside the trap cells.

And the level of those calcium ions, that's the counter.

That is the plant's internal quantifiable memory marker.

And the counting doesn't stop once the trap is closed.

It keeps going.

It keeps counting the internal calcium ion spikes.

If the trigger hairs are disturbed five times in quick succession, accumulating this critical mass of calcium, removing all doubt that it has a wriggling creature inside, then and only then does it commit the energy to inject its digestive juices.

And what's really sophisticated is the error correction.

The error correction is amazing.

If the trap snaps shut after two touches, but then the triggering stops, meaning the calcium concentration never reaches that five touch threshold.

It reopens.

It opens again within a day.

It determined that the object was too small or maybe not even alive, a twig, a botanist's probe, and it corrects its prior very costly judgment.

So that stored information only two touches, then silence actively informs the next move.

It saves valuable resources.

Yes.

And in a similar way, climbing vines show a kind of error correction that absolutely requires memory.

They have this incredibly strong biological imperative to move and find support structures quickly.

To avoid collapsing under their own weight.

Right.

And the analogy of the sweet potato octopus illustrates this perfectly.

When a sweet potato sprouts,

its tendrils don't just coil randomly.

They actively grasp and search for objects, table legs, drawer pulls moving quickly through space to find and use support before they invest in heavier growth.

But the most extreme example of this memory -driven movement has to be the daughter vine.

Cascuda.

It's an incredible plant.

It grows no leaves.

It has no chlorophyll, which means zero capacity for photosynthesis.

So it has to find a host immediately after sprouting or it just dies.

It dies.

And because it lacks chlorophyll, it's this really arresting shade of orange.

It's described as looking like a sleek little worm.

And once it finds a host, it detaches from the ground completely.

Detaches entirely, becomes a fully airborne parasitic system.

So how does it find a host in the first place?

The seedling tip starts by circling the air slowly in a motion that researchers describe as unmistakably like sniffing.

It's smelling the air.

It's sampling the air for chemical emanations, volatile organic compounds that are given off by suitable hosts.

And then it begins to move purposefully in one determined direction toward the strongest signal.

This ability to choose based on external information, this is a core element of that intelligence debate.

It is.

The Latin root of intelligence, interliger, literally means to choose between.

And the daughter makes a clear, determined choice based on information that gathers from a distance.

And it has preferences.

Very refined preferences.

It clearly prefers a juicy, easy to climb tomato over wheat, which is tough and nutritionally poor for the daughter.

And they've tested this.

Oh, yeah.

When it's grown between the two, it notes its neighbors, crosses the air like a baby snake, and aims directly for the tomato, actively shunning the wheat signal.

Consuelo de Moraes, an ecologist on the team that first noted this, said watching it in time lapse reminded her unequivocally of animal behavior.

So once it reaches a potential host,

it doesn't just attach blindly.

No, it begins to wind around it, but it performs this rapid pre -penetration assessment.

It's checking to see if the effort of attachment is going to be worth it.

And lab studies have shown what it's looking for.

Yes.

The clear finding is that it's assessing the host's overall health and the concentration of nutritional energy it's likely to be able to get.

And it gathers this data before it actually penetrates the plant.

Before it penetrates the flesh, likely through chemical signals.

In one experiment, daughters showed a profound preference for nutrient -supplemented hawthorns, and they rejected the ones grown in nutrient -scarce soil.

So if the host is subpar, it just gives up and moves on?

It stops winding within a couple of hours and releases its grip to find new prey.

It's a high stakes strategic choice based on stored info and ongoing assessment.

But if it decides the host is high quality?

Then it begins to wrap more coils around the stem.

And this is where the counting and memory come together as this living memory through movement.

A physical budget.

A physical budget.

The total number of coils it makes reflects the total energy it plans to use for its parasitic operation.

More coils mean more room for its specialized fangs to sink in and draw nutrients.

So its physical structure is a record of its past choice.

And its future intentions.

It's budgeting its physical investment based on its assessment of the host's viability.

It's just a stunning example of complex strategic awareness rooted in stored data.

So to move beyond these really striking individual examples, we have to look at the bigger theoretical framework for how an entire plant operates as a unified intelligent system.

And this brings us to the work of Anthony Trauavas, a leading plant physiologist and his advocacy for network theory.

Trauavas argues that we shouldn't just focus on the individual parts, but on the emergent behavior.

What arises from the sum of all its parts communicating and working together.

Right, and he offers this great evolutionary contrast between animals and plants.

Animals evolved centralized brains because we needed to move quickly over wide areas to find food.

You needed a rapid centralized connection between your sensory equipment and your motor systems.

A complex portable brain was a requirement for hunting and escaping.

But plants took a completely different path.

A totally different evolutionary route.

Their food sunlight is abundant.

It literally bathes them in energy.

So they didn't need a portable centralized brain because they didn't need to move quickly across space.

So Trauavas argues the brain is just one strategy.

Just one and a rather precarious one at that for building intelligence and consciousness.

What's so fascinating about the plant strategy is this core idea of distributed control and modularity.

Trauavas really emphasizes this.

The individual plant with its millions of cells is a self -organizing complex modular system.

Which you can contrast with the fragility of a human system.

Oh, absolutely.

If you destroy a single central organ in a human, the brain, the heart, the entire system collapses instantly.

But plants are incredibly resilient and modular.

They can lose major branches, leaves,

huge sections of their root system and the rest of the organism instantly reallocates resources and just keeps on functioning.

So Trauavas' conclusion is that consciousness in a plant isn't centralized.

It's shared throughout the organism.

And that allows for what he calls local environmental exploitation but in the context of the whole plant system.

So awareness is localized in each part.

But those parts are all communicating and strategizing across the whole system to produce this distributed robust form of consciousness.

And a potential site for this intelligence and memory is highlighted by the botanist Robin Wall Kimmerer.

She points to the meristems.

The meristems.

These are clusters of cells at the tips of shoots and roots that are perpetually embryonic.

They act like plant stem cells ready to be turned into any kind of new tissue the plant needs.

A leaf, a root, a flower.

Whatever is required by the whole system.

There are these hormone and nutrient -packed sites of inventive cell making and they are sensing the results of the plant's perpetual full -body scan.

And this continuous awareness is most obvious in how plants manage their resources and growth.

Right.

The plant is constantly monitoring every single part of its body.

How effectively is each leaf photosynthesizing?

How much moisture is each root pulling in?

All of that information is constantly being transmitted through the network.

And if a branch or a leaf is underperforming?

It is immediately flagged by the system.

It receives fewer resources, less water, fewer sugars, and growth will be directed to other, more productive areas.

The system is prioritizing investment where it gets the greatest return.

And if that part continues to underperform, it will actually be cut off.

It will be physically blocked from essential supplies and allowed to whitter.

It's energy reallocation and resource budgeting in real time and it requires continuous strategic decisions based on incoming data from all over the body.

The source material gives a brilliant illustration of this with the giant red cedars in Washington.

It's such a great image.

When you stand inside a thick stand of these cedars, the forest floor is almost completely dark.

Because the canopy is so dense.

So dense.

The thick glossy green fronds only grew outward to the available light and the massive trunks inside the stand are completely bare except for a few high up shriveled leafless twigs.

And those leafless twigs are described as ancient history.

That's what they are.

They were branches that once grew inward when there was still enough light but they were eventually allowed to wither and die because they were no longer performing their function.

They were taken out of service to save resources.

And this constant self -adjusting dynamic requires the plant to remember what is happening in its body at all times.

Triwavus calls it a running commentary.

The plant is constantly making choices, recalibrating fluid pressures, deciding where to allocate energy just to maintain its equilibrium and stay upright.

It really highlights this profound biological awareness that's suffusing the whole plant body.

It does.

The plant's ability to stay upright, function as a whole, and strategically invest its resources requires a continuous distributed memory of its own structural, energetic, and environmental conditions.

So if the plant is this self -organizing system with distributed awareness,

its entire physical body becomes a record of its life story.

That's the idea of physical memories.

Yeah.

The body itself is an experiential map.

The resulting structure of the plant, the angle of the branches, the depth of the roots is a direct physical record of the conditions it faced and the choices it made.

Exactly.

The newest shoots account for what's happening now while the oldest parts are a physical record of conditions that came before.

So in a way, the plant is a kind of biological ledger that you can read just by looking at it.

That's a perfect way to put it.

In us, a memory is a connection between neurons.

In a plant, the memory might be a physical pathway,

a root structure that marks where moisture used to be found, or a permanent bend in a trunk that tells the story of sunlight that was suddenly shaded out years ago.

So the substrate of the plant's memory is its own structure, its own hardened tissues instead of brain matter.

Right.

And this is why spatial memory is so dominant in plants, which is actually similar to how spatial memory is our keenest form of memory as humans.

That's a holdover from our hunting and gathering days, right?

Quickly committing the layout of a landscape to memory was crucial for survival.

Absolutely.

Our portable centralized brain evolved to serve that need for movement and navigation.

And you can speculate.

What if the primary food source for early animals had been abundant immovable sunlight just like it is for plants?

Evolution might have favored something completely different.

Maybe flexibility, the limitless ability to build new photosynthesizing arms on short notice, instead of the centralization and fragility that comes with a portable brain.

You could just drop an arm if it wasn't in a good spot to catch food.

Nonchalantly.

Yeah.

Because the memory isn't stored there, it's stored everywhere.

And to tie all of this together, we can turn to the work of Peter Godfrey Smith, who traces the emergence of the animal mind.

He provides this really powerful framework for understanding how intelligence and memory might have originated in any living system.

Godfrey Smith traces the animal mind back to the very first multicellular organisms that could move on their own, the ones that could swim or scoot across the seafloor half a billion years ago.

And he asks this fundamental question.

Were these early animals having experiences?

Were they sensing their environment and building memories of it as they moved?

And the biological principle he outlines is so fundamental to understanding memory.

It is.

He says nothing is gained biologically from taking in information that is not put to use.

If an organism is sensing its world and that sensing changes its behavior, then that information must be stored.

So if these creatures were moving through space, they were constantly encountering new sensory information.

It would be a total evolutionary waste not to store that information.

A total waste.

You have to build a lasting picture of the world to draw on later.

Memory, therefore, becomes an evolutionary requirement.

So Godfrey Smith concludes that the ability to move with purpose came first.

And the ability to sense and store those sensations, memory, it caught up automatically.

The very first animal to experience this world was likely the first one that moved by its own effort.

And that principle applies directly and powerfully to the plant kingdom.

It absolutely does.

Plants move through growth.

It's a slow,

purposeful, determined movement.

And they're tasting it all as they go, taking it count, and saving what they learn for later use in their own physical structure.

The daughter is probing the chemical contours of the air.

The mallow is tracking the sun.

And the memory flower, Nasa Boissoniana, is experiencing a bee, recording that precise time interval in itself, and then deciding exactly when to raise its next stamen to experience another one.

This isn't mysticism.

No, it's a logical, necessary evolutionary strategy based on stored data.

So what does this all mean?

Well, I think we've established that plant memory is a real measurable phenomenon.

We see it in their ability to predict pollinators, to count the passage of cold in time with molecular switches.

To strategically allocate resources across their whole distributed system to choose the best hosts through chemical assessment.

Right.

And this ability to store and apply past experience allows for truly intelligent adaptive behavior across the entire organism.

And just the knowledge that plants evidently possess this complex elastic memory, memory that lets them experience and adapt to their own specific world, that's enough to fundamentally change how we view our planetary companions.

Because if a being can remember the specific contours of its world, and it can make forward -looking, high -stakes decisions based on those memories, then you have to say it has experienced its world.

Which invites a much more radical, a much more generous view of plant life.

It does.

Maybe that generous view should extend to them some measure of subjectivity.

They experience and remember their world as they move through it.

And that brings into focus not just a world of inert things, but - But rather a universe of selves.

Thank you for sharing your sources with us for this deep dive.

We look forward to exploring what else is hidden in the complexities of the biological world next time.