Are plants more intelligent than we assumed?

Mar 04, 2014
Plants are also able to make complex decisions. At least this is what scientists have concluded from their investigations on Barberry (Berberis vulgaris), which is able to abort its own seeds to prevent parasite infestation. Approximately 2000 berries were collected during this study from different regions of Germany, examined for signs of piercing and then cut open to examine any infestation by the larvae of the tephritid fruit fly (Rhagoletis meigenii). Credit: Steffen Hauser/ botanikfoto

Plants are also able to make complex decisions. At least this is what scientists from the Helmholtz Center for Environmental Research (UFZ) and the University of Göttingen have concluded from their investigations on Barberry (Berberis vulgaris), which is able to abort its own seeds to prevent parasite infestation. The results are the first ecological evidence of complex behaviour in plants. They indicate that this species has a structural memory, is able to differentiate between inner and outer conditions as well as anticipate future risks, scientists write in the renowned journal American Naturalist —the premier peer-reviewed American journal for theoretical ecology.

The European or simply Barberry (Berberis vulgaris) is a species of shrub distributed throughout Europe. It is related to the Oregon grape (Mahonia aquifolium) that is native to North America and that has been spreading through Europe for years. Scientists compared both species to find a marked difference in parasite infestation: "a highly specialized species of tephritid fruit fly, whose larvae actually feed on the of the native Barberry, was found to have a tenfold higher population density on its new host plant, the Oregon grape", reports Dr. Harald Auge, a biologist at the UFZ.

This led scientists to examine the seeds of the Barberry more closely. Approximately 2000 berries were collected from different regions of Germany, examined for signs of piercing and then cut open to examine any infestation by the larvae of the tephritid fruit fly (Rhagoletis meigenii). This parasite punctures the berries in order to lay its eggs inside them. If the larva is able to develop, it will often feed on all of the seeds in the berry. A special characteristic of the Barberry is that each berry usually has two seeds and that the plant is able to stop the development of its seeds in order to save its resources. This mechanism is also employed to defend it from the tephritid fruit fly. If a seed is infested with the parasite, later on the developing larva will feed on both seeds. If however the plant aborts the infested seed, then the parasite in that seed will also die and the second seed in the berry is saved.

When analysing the seeds, the scientists came across a surprising discovery: "the seeds of the infested fruits are not always aborted, but rather it depends on how many seeds there are in the berries", explains Dr. Katrin M. Meyer, who analysed the data at the UFZ and currently works at the University of Goettingen. If the infested fruit contains two seeds, then in 75 per cent of cases, the plants will abort the infested seeds, in order to save the second intact seed. If however the infested fruit only contains one seed, then the plant will only abort the infested seed in 5 per cent of cases. The data from fieldwork were put into a computer model which resulted in a conclusive picture. Using computer model calculations, scientists were able to demonstrate how those plants subjected to stress from parasite infestation reacted very differently from those without stress. "If the Barberry aborts a fruit with only one infested seed, then the entire fruit would be lost. Instead it appears to 'speculate' that the larva could die naturally, which is a possibility. Slight chances are better than none at all", explains Dr. Hans-Hermann Thulke from the UFZ. "This anticipative behaviour, whereby anticipated losses and outer conditions are weighed up, very much surprised us. The message of our study is therefore that plant intelligence is entering the realms of ecological possibility."

But how does the Barberry know what is in store for it after the tephritid fruit fly has punctured a berry? It is still unclear as to how the plant processes information and how this complex behaviour was able to develop over the course of evolution. The Oregon grape that is closely related to the Barberry has been living in Europe for some 200 years with the risk of being infested by the tephritid fruit fly and yet it has not developed any such comparable defence strategy. These new insights shed some light on the underestimated abilities of plants, while at the same time bringing up many new questions.

Explore further: Plants compete for friendly ants

More information: Katrin M. Meyer, Leo L. Soldaat, Harald Auge, Hans-Hermann Thulke (2014): "Adaptive and selective seed abortion reveals complex conditional decision making in plants." The American Naturalist. Vol. 183, No. 3, March 2014

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zorro6204
2.4 / 5 (5) Mar 04, 2014
Slow down just a minute, "intelligent" is not a correct word for a biological machine. You could say its software is more complex than we assumed, that would be reasonable.
Rimino
Mar 04, 2014
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Modernmystic
3 / 5 (5) Mar 04, 2014
...is able to differentiate between inner and outer conditions...


So can a rock when it hits it's melting point. I don't call that complex behavior.

What they're talking about isn't "anticipatory" behavior or being able to "differentiate" on any kind of level other than mechanistic. This is an interesting MECHANIC of the structure of a plant that's being described, it has nothing at all to do with intelligence any more than a piece of ferrous iron being attracted to a magnet...
Rimino
Mar 04, 2014
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Modernmystic
2.2 / 5 (5) Mar 04, 2014
Our problem with the perception of intelligence of lower level organisms consist in fact, we cannot recognize the tiny density gradients, which these organisms utilize for their "decissions". Our conclusion therefore is, they do behave randomly and they don't analyze any problems during it.


No that isn't our problem with the perception of intelligence in plants. The "problem" is that planets aren't intelligent and some people view this as a problem. It's no more a problem than the non existence of the tooth fairy...
Rimino
Mar 04, 2014
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krundoloss
5 / 5 (2) Mar 04, 2014
If however the infested fruit only contains one seed, then the plant will only abort the infested seed in 5 per cent of cases


Why would it abort the seed? It has already grown it, so its not saving any resources. The purpose of the fruit is to provide nutrients for the seed, so even if there is no seed in the fruit, there will be other seeds in the vicinity that may benefit from the nutrients of the fruit. These things are not decisions, but rather just behavioral features of the organisms. After all, we don't call the individual plant cells "intelligent" simply because they make biomechanical "decisions", do we?
javjav
2.3 / 5 (3) Mar 04, 2014
Modern theories are pointing to a more progressive intelligence concept. According to these theories the Intelligence, consciousness, or decision-making capability in general is not a black or white property, something that an organism can have it or not, but it is more a kind of progressive capability directly related with the complexity of biological systems. According to this, a plant can also have a little bit of it. Bees have it millions of times more developed than plants, and humans millions of times more than bees. But even a bacteria can develop a tiny bit of it. So it would be perfectly correct to talk about "plants intelligence". It may sound weird, but I think the traditional concept is more weird (in the evolution chain, intelligence pop up from nowhere). A good article and references here: http://www.quantu...ive.html
RealScience
5 / 5 (4) Mar 04, 2014
Slow down just a minute, "intelligent" is not a correct word for a biological machine. You could say its software is more complex than we assumed, that would be reasonable.


Slow down another minute, zorro6024 - humans are biological machines, too!

So that's pretty funny coming from a biological machine like you presumably are ... did you mean it humorously?
Rimino
Mar 05, 2014
This comment has been removed by a moderator.
Rimino
Mar 05, 2014
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zorro6204
5 / 5 (1) Mar 05, 2014
To the above, let me say this. In science one must propose a mechanism for a given theory to be plausible. For example, as Sean Carroll so eloquently points out, life after death is impossible because (a) there is no combination of forces and particles that could carry information out of a body at death (to wherever) and (b) no force or particle we haven't discovered could act at the macroscopic level.

A plant lacks any system that could express intelligence, no neurons, no brain cells. A plant acts and reacts purely through coding in its DNA, much like a machine would. Stimulus A happens, subprogram B is invoked, no reason, no judgement, no thought. Indeed, most of the animal kingdom is no better, just a collection of cells and programs until you reach the level of mammals and birds. Intelligence is not just a set of complex instructions.
RealScience
3 / 5 (2) Mar 05, 2014
A plant lacks any system that could express intelligence, no neurons, no brain cells. A plant acts and reacts purely through coding in its DNA, much like a machine would.


A neuron reacts to molecules transmitted from other neurons, purely through molecular interactions, much like a machine would. So if you think that biological machines aren't intelligent do to being mechanistic, speak for yourself,

The intelligence arises from the number of neurons and the complexity of the interactions between neurons, not from the mechanics of the interaction.

As for DNA, DNA is the disk drive of the cell, the RNAs are the processing power.
Several hundred to several thousand copies of each of hundreds of thousands of RNAs and proteins interact in a complex web, with a given RNA often interacting with hundreds or even thousands of other RNAs and proteins, and with DNA regulation regions.

-continued-

RealScience
3.2 / 5 (5) Mar 05, 2014
The RNA-centric interactome in every cell is far more complex than the synapse/axon/dendrite activity of a single brain cell.

Where the brain beats RNA is on speed and on number of units closely interacting.
The brain interactions are in milliseconds to seconds rather than seconds to hours, or very roughly three orders of magnitude faster.

However that is not intelligence - current computers are more than twice that many orders of magnitude faster than our neurons, and that doesn't make computers intelligent.

So the brain's intelligence wins because we have ~10^11 neurons, each interacting tightly with ~100 to 10,000 others.

In contrast, while each cell's RNA interactions are more complex than a neuron's electrical activity, the cells only interact closely with dozens of neighbors and have global, rather than individual, actions with billions of other cells.

So our brains are MORE intelligent than plants, but that DOESN'T mean that plants have no intelligence.
Rimino
Mar 06, 2014
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jahbless
1 / 5 (1) Mar 08, 2014
Oh, you bleeding humans. The article title's SHOULD be "Is human ratiocination more plant-like than we realized?"
Bonia
Mar 08, 2014
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Bonia
Mar 08, 2014
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mitchslagghorn
1 / 5 (1) Mar 08, 2014
You really have to think outside the box on this one. Plants think and communicate,
but not in the fashion that animals and humans do. It is incredibly hard to explain,
because we consider our own physical properties and mechanisms to be
the only accepted measure of cellular construction that has the ability. Just as
we can only visualize a life form as a carbon based creature. This planet is a mixed
bag of many types of life, to assume you know all and every frequency that exists,
is truly an example of how simple we are. Trees are perhaps the most intelligent.
Just because they don't speak your language, or communicate on a frequency that
you can understand, doesn't mean they aren't listening. It's quite possible,
they record everything.
"Think and wonder, wonder and think." ― Dr. Seuss
Bonia
Mar 09, 2014
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Bonia
Mar 09, 2014
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Captain Stumpy
3 / 5 (2) Mar 09, 2014
To distinguish the impacts of rain droplets from another touches requires some sort of intelligence.

@Zephir
I am not sure I can agree with that
from the wiki page
with a trapping structure formed by the terminal portion of each of the plant's leaves and is triggered by tiny hairs on their inner surfaces. When an insect or spider crawling along the leaves contacts a hair, the trap closes if a different hair is contacted within twenty seconds of the first strike. The requirement of redundant triggering in this mechanism serves as a safeguard against a waste of energy in trapping objects with no nutritional value.

that would mean it is not intellectual, but mechanical
take your hand: it can be stimulated to contract (without intelligence) via electrode which is the mechanical response due to stimulation
you would not assume the hand is intelligent in itself should this happen (against your wishes) and try as hard as you want, you cant fight against direct stimulation either
Rimino
Mar 10, 2014
This comment has been removed by a moderator.
edward_ponderer
3.7 / 5 (3) Mar 10, 2014
Just imagine what human beings could do if we were sufficiently mutually responsible to evolve into such parallel levels of Whole-Humanity intelligent complex behavior. Would we be stymied by issues economic to ecological? If we could but educate ourselves in the direction of a wholesome global integration, a bright future would await us as Nature's full partner instead of continuing as its pathetically naive opponent, little cells incapable of forming a healthy global body instead of chaos.

Should such wondrous communities in the plant and animal kingdoms really be just scientific curiosities for us, or something from which we hope to induce some snake oil elixir? Should they not be signposts for us of where we should use our special gift of intelligence to travel, and of the ego that we must work around to get there?
ForestofPeace
3 / 5 (2) Mar 10, 2014
..as expected ..!
We are so excited to see what the future finds out everything in our kaleidoscope. The question is, on what basis of communication, keep in mind we are all caught in our language.
Quibble "intelligence", writes http://www.stangl-taller.at/
Non-Psychologists among intelligence always something great and Comprehensive ago, many psychologists, however, as something very sober - just a small cog of the many who keep us going. There is no single definition of intelligence, and there are almost as many theories about them as researchers who deal with it. Most theories, however, have in common that they see intelligence as an ability to find their way in new situations by understanding or to solve problems by thinking. Crucially, however, that this is not possible by experience, but the rapid detection of relationships. In other words: Smarter have faster track of an unknown territory in general.
Captain Stumpy
5 / 5 (2) Mar 11, 2014
Look, I'm not pretending here, that the Venus traps are Einsteins on their own - but their reactions aren't just some primitive feedback. It comprehends a decission driven process

@zeph
I guess you misunderstood my post?
it does NOT "comprehends a decission"
I said it was primarily a mechanical reaction to a situation.
again, it is a matter of stimulus and response
as to the the viability of intelligence behind it, there is no guarantee based upon the trap closing (because there was a mechanism triggered due to its evolution of it over time) that there is an intelligence in the reaction
IF there was an intelligence to the reaction, then modern researchers would NOT be able to trigger the trap to close themselves, wasting the energy. It would ONLY close when it had digestible prey in the trap. this kills it as it can only close/open a finite amount of times
read the link:

http://www.botany...trap.php
Bonia
Mar 11, 2014
This comment has been removed by a moderator.
Captain Stumpy
5 / 5 (2) Mar 11, 2014
two trigger hairs must be touched in succession within 20 seconds of each other or one hair touched twice in rapid succession, whereupon the lobes of the trap will snap shut in about one-tenth of a second.

@zeph
like I said, it is primarily a mechanical reaction to a situation
proof?
From MY LINK ABOVE
If the leaf does close without a victim, it will re-open in a few hours. According to Lloyd (in George 1962), the traps can only catch about three victims before the leaves turn black and die. And even if the trap fails to catch anything, like when you tease it by touching a hair with a small brush, it can only reopen and close again about seven times! So, don't tease the flytrap!

IOW – even YOU could STIMULATE the trap to close without prey, and it would eventually kill the leaves over too many stimulations, meaning that it is NOT an intelligence based decision
if it were INTELLIGENCE based, it would NOT allow leaves to close without prey to save energy/life of leaves
Bonia
Mar 11, 2014
This comment has been removed by a moderator.
Captain Stumpy
3.7 / 5 (3) Mar 11, 2014
It's intelligent in the scope of perceptions, which the Venus trap is capable of. Try to realize, this flower is a blind and it cannot see, what you can see. In context of what it's actually capable to detect it with its hairs it behaves intelligently

@Zeph
personal conjecture without evidence

there is nothing wrong with having a stimulus response mechanism within an organism for mechanical actions. Your arm/hand is a perfect example of it, like I showed above
the intelligence is NOT in the arm/hand which makes the movement, but in the brain which gives the order (and you CAN override this mechanism with electrodes) just like the Flytrap

I am not saying that I understand plant intelligence, nor am I saying that plants dont have it (I dont care)

I was pointing out that the mechanism of the Flytrap is primarily a mechanical reaction to a situation, much like your arm/hand
Bonia
Mar 11, 2014
This comment has been removed by a moderator.
Captain Stumpy
5 / 5 (3) Mar 11, 2014
And your replies are primarily driven with negativism

@zeph
no, more like REALITY
I'm just talking about secondary aspects of these reactions

no, you are posting conjecture not supported by evidence
Your perception of intelligence is too anthropocentric

I guess you missed the part above where I said
I am not saying that I understand plant intelligence, nor am I saying that plants dont have it

again, I am actually trying to be open to new ideas, however, there is NO supporting evidence that the closing leaves of the flytrap are anything other than mechanical in nature (as shown in my link)
IOW – not intelligence based

nor am I being anthropocentric. I believe intelligence is VERY subjective
I am trying to get you to focus on what IS important as the closing leaves are not what you are inferring

your flatworm example is much better, and FAR more interesting
Bonia
Mar 11, 2014
This comment has been removed by a moderator.
Captain Stumpy
5 / 5 (3) Mar 11, 2014
Not surprising to hear from mainstream science proponent. Many of them cannot recognize the personality traits very well (many of them are borderline autists like the Sheldon Cooper). But in real life it's good to recognize, how smart is the person standing against you

@Zeph
the above is a perfect example of your difficulty of comprehension, and perhaps this is a language issue?
Subjective: existing in the mind; belonging to the thinking subject rather than to the object of thought (opposed to objective)
IOW – I was agreeing with you (in regard to intelligence)
given that the definition of intelligence must be considered in the aspect of the object taken, it is difficult to define intelligence of animals/AI with any clarity
this would also be true with plants or ET's

as for your "mainstream" crack... like I said before and will continue to do: PROVIDE EMPIRICAL DATA to support your argument and I will be more amenable to the inferences of your alternative points of view
Bonia
Mar 11, 2014
This comment has been removed by a moderator.
Bonia
Mar 11, 2014
This comment has been removed by a moderator.
Captain Stumpy
5 / 5 (2) Mar 11, 2014
mainstream science are typical with their schematic black&white vision

@Zeph
so you are here to TROLL then?
This is personal conjecture without evidence
distinguish only two types of creatures: bright and dull

conjecture without evidence
They seek for boundaries, not for connections

they seek to classify, which INCLUDES boundaries AS WELL AS CONNECTIONS
who did provide the support for me stance - or not?

NOT
I just quoted the Wikipedia

and I ADDED a BIOLOGY site link
I'm perfectly aware that the dull people cannot be convinced with anything

and WE are aware that pseudoscience crackpots are so fanatical they cant see REALITY before them
given your LACK of empirical support, you prove ONLY that you are:
making conjecture
STUPIDLY refuting KNOWN SCIENCE with conjured supposition
APPLYING attributes to a system which does NOT prove your speculations

you are TROLLING and applying personal hallucinations
I am not responding to more of your STUPIDITY
Bonia
Mar 11, 2014
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Bonia
Mar 11, 2014
This comment has been removed by a moderator.
Bonia
Mar 11, 2014
This comment has been removed by a moderator.
Captain Stumpy
5 / 5 (2) Mar 11, 2014
It's solely driven with ignorants, like Mr. Stumpy here.

@Zeph
you should read that paper... there is a LOT of YOU in it...
http://www.prince...20BW.pdf

especially given that you cant tell the difference between MECHANICAL ACTION and an INTELLIGENT THOUGHT (I will give you a hint... the first involves the leaves of the Venus Flytrap, as proven by me earlier, because if it were driven by INTELLIGENCE then it would NEVER close upon an empty trap which would then waste energy and shorten its life further... in fact... if it had INTELLIGENCE, it would be able to tell the difference between PREY and STIMULATION WITH A BRUSH BY SCIENTISTS!)

IOW – you are a TROLL
and ignorant, to boot
Bonia
Mar 12, 2014
This comment has been removed by a moderator.
Captain Stumpy
5 / 5 (2) Mar 12, 2014
Didn't you want to say, "if it had an eyes" instead?

@Z
no.
It has no needs to distinguish it, because the "brushes of scientists" don't regularly occur in nature

wrong. There IS other stimulus in nature that can trigger the leaves, from animal hide/hair to blowing particles
Do you really believe, our intelligence qualitatively differs from this one of Venus trap plant?

differs? Yes
is it better? Not necessarily
it differs because out intelligence allows us to manipulate the environment in ways that the Flytrap cannot even fathom
that is all I will state, however, because there is no clear definition for intelligence and it tends to be subjective and malleable (our dogs are intelligent in their own way, as well as Dolphins, birds, etc etc)
anywallsocket
not rated yet Mar 17, 2014
The plant in itself is half the picture in which you'd find "intelligence".
To explain how a plant reacts, you need to see the environmental half of the picture.
The plant reacts WITH the environment. They are a "complex system" when viewed together. So if the plant is to be called a "machine" one should point out its function as well, which if anything, would be something like 'Mutual recursion' in mathematics.

The alleged "intelligence" likely comes from this intimate "stimuli - reaction", "cause and effect", "the earth is one organism", or whatever RELATIONSHIP these organism's share with the environment. Sorry to yell.

It's harder to believe in the case of the dropping of the plant, where we measure an active reaction to its change in environment; as it does. Whatever the total plant reaction to being dropped was -- it was what it did last time, or what its lineage did -- but done with less resistance this time.
dedereu
1 / 5 (1) Apr 27, 2014
Anyone, in his garden, like me, has observed that fruits with worms are aborted or falling down quite earlier : true for apples, pears, figs, plums, etc......
It is well known, and typical of any living organisms which are more intelligent trough evolution.

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