Thank you to everyone for being here.
I'm sorry I cannot speak in your wonderful language,
but it's all the same a pleasure to be here in this wonderful place,
the right place to speak about plants.
OK, let's start immediately because we have not too much time.
And I will show you now four slides in a very fast sequence.
This one.
And, the last one.
Well (Laughs), this one ...
It's a very easy psychological test
we did some years ago to the university students.
We asked these university students to tell us what they saw in the slides.
And 96% of the people interviewed
told us that they saw just deers, elks, frogs,
and for the last slide,
98% of the people will tell you
that there is an adult man and a young girl.
Well, all these slides have in common
the fact that 80% of the slides is made by plants.
But our brain is filtering out all this stuff about plants.
And, it's a well known feature of our brain.
It's called Plant Blindness.
It's the inability to see or notice the plants in the environment.
It's a kind of tool that protects our brain to be overloaded
with a lot of information about this useless green stuff.
We evolved in a forest
and it was much more important for us
to be aware of animals and other humans,
and not to be overloaded with all this information about green.
Well, this was a nice tool at the beginning of our evolution,
but today, it's a problem.
Today, this Plant Blindness prevents us, for example to know this data,
this is the unbelievable data,
99.7% of the biomass of the planet is made by plants.
So, everything that - I would say that the life of the planet,
it's a green place, it's a green life.
All the animals altogether, human included, is just 0.3%.
So it's unbelievable that we don't know, actually, how these plants work
and we are all the time underestimating their amazing abilities.
Well, let's have a look at the beginning, how a plant is made.
A plant is a sessile organism.
Sessile means that it cannot move.
The plants cannot move from one place to the other.
But they can move a lot.
Ops, I'm sorry, I do not know what's happened.
And the second, the second point is that plants have no organs.
This is an unbelievable difference with the animals.
So I mean - animals concentrate specific functions
inside specific organs.
So we have eyes to see, we have lungs for breathing,
we have the stomach to digest and so on.
But the plants evolved not to have any organs,
because having an organ is too dangerous,
for plants that have to be predated, to be eated by animals.
So you can imagine that a single insect,
just eating a little bit of your brain would be enough to kill you, no?
Ah, so this is why the plants have no organs.
But, having no organs doesn't mean that they have not the function.
This is an important point.
In other words, plants are able to see without eyes,
they are able to hear without hearing,
they are able to taste, and to smell,
and to breath without the organs.
And they are also able to make calculations,
memorize, learn without brain.
Now the point about plants is that they cannot move.
But actually, they move a lot.
There are passive movements in plants,
like in this pine cone, no?
The opening and the closing of a pine cone,
that has been used for the production of new passive materials.
Or, this very nice Erodium cicutarium.
This is a seed, that you can see.
Just with the change in the humidity it's turning,
and uses this ability to enter in the soil,
and so it's like a spermatozoa, it works very well,
and you can see that some of them are also able to enter in the soil.
Now, what is amazing about that
is that they do this without using any energy.
So they have no muscles, look, it was able to enter.
So, they use no energy, they have no muscles,
and it's just the way the material is made
that is amazing, that makes possible this wonderful movement.
Of course, there are active movements, some of them are very fast,
like in the case of the venus flytrap, dionea, it's a carnivorous plant,
we know that it's a very fast movement.
Many of them can be exhibited
just by making a faster - the time lapse,
the so called... the time lapse technique.
And so we can see this graceful movement
like in this case, this a young bean moving,
it's just three hours of time, it's not a week.
So the plants move a lot, and we can see here,
this growing of some flowers, no?
They grow altogether and even this growing together is important,
because it's an important moment of their social life.
So they are really learning how to stay together
during this first phase of their life.
And now I would like to put our argumentation a little bit further.
Can we tell that plants are conscious organisms?
So because I'm pretty sure that they are intelligent,
I will not discuss with you about that.
Plants are intelligent, and they are able to solve problems,
and this is my preferred definition of intelligence.
Now the point is, are plants conscious?
Consciousness is - are plants aware of their position in the environment?
So, it's a problem to find right definitions about consciousness.
It's normally defined by removing something.
Michio Kaku is a quite famous physicist.
And he wrote recently this book "The Future of The Mind,"
and as a physicist, he gave a definition of consciousness
that's quite understandable.
Michio Kaku: Consciousness is
the number of feedback loops required to create a model
of your position in space, with relationship to other organisms,
and finally in relationship to time.
Stefano: So, consciousness is just your ability to build a model of yourself
in relation to the space, to the other organisms, and to the time.
Are plants able to do that?
OK. Let's have a look.
First of all ...
Michio Kaku: So think of the consciousness of a thermostat.
I believe that even a lowly thermostat has one unit of consciousness.
That is, it senses the temperature around it.
And then we have a flower,
a flower has maybe, ten units of consciousness.
It has to understand the temperature, the weather, humidity,
where gravity is pointing.
Stefano: Well, so, for Michio Kaku, the sensing, no?
It's the first level of consciousness.
Plants are unbelievably more sensitive than animals.
A single plant is able to detect
at least 20 different chemical and physical parameters all the time.
Among them, there are all the -- our common sense, let's say,
but also something a little bit strange,
as electrical gradient, chemical gradient, magnetic fields,
and, or, heavy metals and so on, pathogens.
So we know that plants, for example,
are very sensitive to gravity.
And as every living organism on the Earth,
we can see here maize growing according to gravity.
But it's less well known that plants are also able to sense vibrations.
And so we can see here how the roots of the plants
grow toward the source of sound.
So they are able to sense the sound, and they are able to grow
toward the source of the sound.
And also, they are able to produce a sound.
(Clicking)
This kind of click is very amplified sound
of a growing ... growing roots.
So, when the roots during -
this is just in real time, so it's few times, few seconds.
A growing root is producing specific sounds
that probably are used by the other root apex,
to have information about the position of the roots in the soil.
Well, let's go on to the second point,
to the first level of consciousness, space.
Michio Kaku: And then finally we go into the reptilian brain,
which I call level-one consciousness,
and reptiles basically have a very good understanding
of their position in space.
Especially because they have to lunge out, and grab pray.
Stefano: OK, so, reptiles are very well aware of the space.
Is this the same for the plants? Let's have a look.
This is a, uh, this is a cuscuta plant.
Cuscuta plant is a parasitic plant
that needs to find a host in a very short time before dying.
And you can see how this plant is immediately directing
towards the tomato plant, finds it
and parasitising the tomato plant.
Well, this is quite trivial.
It's just a chemical driving the information up to the plant.
It's volatile.
But, look at this case.
This is the same plant that has to take a decision,
because it's in the middle, between wheat and tomato.
And all the time, it's choosing tomato.
Well, because tomato, it's much much easier to parasitise.
But if there is no tomato, even wheat can work.
OK, and this is something simple.
Let's, let's do something a little bit more curious.
This is a bean in my lab and this is a support.
You can see how it is moving, for reaching the support.
So I mean, this plant knows exactly where the support is, the pole is.
And it's trying to do all its best for reaching it.
I don't know if you can see,
but the apex of the shoots already made a kind of hook
in the right position, even if the plant didn't touch until now, the support.
And you can see also the movement,
it's a wonderful movement. It's just, in this case, just passive,
just based on multi traders, look at the hook, in the apex.
And, almost ...
Eh?
Another try, and it's not enough.
And you can almost feel the effort, no?
And, and look at the leaves now, that they reach the support.
Now, it's much much quieter, calmer.
Anyway, so we know that the bean is aware of the pole.
OK? It's the result of something more impressive
because, look in this case, I am putting a pole among two beans.
So, there is the sensing phase.
They know there is a pole and they start to compete.
And look when the first one is winning, the winner,
the other one changes direction.
So, you can repeat this experiment 100 times,
and 100 times you will get the same result.
So, this means that the second plant is not just aware of the support,
it's also aware of another organism, of another plant,
and it is aware of what the other plant is able to do. OK?
Great. Social life.
Michio Kaku: Then we have level-two consciousness, the monkey consciousness.
The consciousness of emotions, social hierarchy.
Where are we in relationship to the tribe?
Stefano: OK. I don't want to spend too much time,
because the social life of the plants is very well known.
Plants are social organisms,
at any level of their evolution, from Chlamydomonas -
this is a single algae, unicellular algae that shows weird behaviour.
So, a kind of social movement like the one of the hands.
These winged shoots, look how they oscillate altogether.
OK, this is a, this is something very easy to do, but it's not easy at all.
You need to be in sync with your neighbor to do this,
so you need to be well aware of what the movement of your neighbors are.
And kin recognition.
It's something unbelievably interesting.
So we know that today that plants have different behaviour
according to the degree of relativeness of the other plants.
So, normally, for example, beans, the very common bean, are cooperating,
when they are in the same pot, they are related.
But when the two plants are unrelated, they are normally competing.
And, in a wood, it's a huge network
of plants interacting each other.
For example, we know that - this is a graph showing that a single tree
is linked to 47 different trees, and they use
this network for sharing information,
for sharing even food and water, nutrients and water.
Well, there is much more with plants.
We have not too much time to show all of the -
the wonderful things about plants.
Plants, for example, are able to memorize.
They are able to memorize and to learn.
We demonstrated just a few months ago that it's possible to teach
a mimosa sensitive plant not to close anymore
when there is a non dangerous stimulus.
And, this sensitive plant is able to maintain the information for 40 days.
So I mean, the memory lasts at least 40 days. That is a lot.
And in the average, the memory of an insect is just 24 hours.
Even for me, 40 days is a lot.
(Laughter)
And so, it's amazing to see that
plants are able to maintain information for so long.
And, just a last thing.
From my point of view,
intelligence and consciousness are real biological phenomenons.
So they can be studied, as real,
they need to be studied as real biological phenomenons.
And it's something like reproduction, I mean,
reproduction is completely different in bacteria, phangiae, and humans. OK?
But there is a common background
that means that the phenomenon is reproduction,
it's the same for intelligence, it's different, but always the same.
Thank you very much.
(Applause)