[ScottAnfield]

I was just wondering if there is such things as intelligent plants. I saw a tree with spikes on it when I was living in Spain http://www.worldofstock.com/closeups/NTR1592.php and my mum told me that it was to stop animals climbing up it to get its fruit. I thought how does a tree know that an animal is climbing up it to get its fruit? It has no eyes to see the animal and no brain to process the fact that an animal is climbing up on it, let alone that an animal is trying to steal its fruit. On top of that, how does it know to grow spikes and how does it know that these spikes will deter animals?
This occurs with other trees and plants in the Plantae Kingdom, such as cacti. How do they know, how did they learn?
I assumed that it was evolution, natural selection, but why would a tree grow spikes in the first place? They do not have any use to the tree?
Any thoughts?

[Polybius]

Hello ScottAnfield,
This is a tricky one. Firstly, how does one define intelligence? Some can say that only we are intelligent but to me all life is intelligent. Intelligence is information and all life stores information. A definition in a dictionary would read: The capacity to acquire and apply knowledge.

--"If intelligence is the capacity to acquire and apply knowledge, then, absolutely, plants are intelligent," agrees Leslie Sieburth, a biologist at the University of Utah in Salt Lake City.--

But its not that simple. Plants are coded with DNA and genes that create the plants interior and exterior structure and defines the plants objectives. Animals too are created in this way. You ask how do plants know to grow defensive systems well it's in their DNA just like with animals. You could just as well ask why do animals grow eyes. We are all coded to do this. Why do they grow spikes? Why do sharks grow teeth? Survival. Every living organism lives to try and survive and reproduce.

Plants do seem to yield some sort of 'intelligence' as they can carefully consider their environment, speculate on the future - planning ahead, conquer territory and 'enemies' - being know to challenge other species which shows very basic intellect. They can communicate with each other and insects by coded gas exhalations. They also seem to act differently in the same situations.

--For philosophers, one of the key findings is that two cuttings, or clones, taken from the same "mother plant" behave differently even when planted in identical conditions.--

Plants do have quite complex behavior patterns but whether you can really call this a 'higher intelligence' is just anyones opinion. I think i would say that plants are intelligent as all life is but plants aren't at all on the same level as us.

--There is still much that we do not know about how plants work, but a big part of intelligence is self-consciousness, and plants do not have that," says Heike Winter Sederoff, a plant biologist at N.C. State.--

Here's a good quick read on plant neurobiology: http://www.plantneurobiology.org/

[eyeboy]

Originally Posted by Polybius Hello ScottAnfield, But its not that simple. Plants are coded with DNA and genes that create the plants interior and exterior structure and defines the plants objectives. Animals too are created in this way. You ask how do plants know to grow defensive systems well it's in their DNA just like with animals. You could just as well ask why do animals grow eyes. We are all coded to do this. Why do they grow spikes? Why do sharks grow teeth? Survival. Every living organism lives to try and survive and reproduce. Here's a good quick read on plant neurobiology: http://www.plantneurobiology.org/

I think this is a great forum and surprised its only been answered now. Anyway by the by...

there are two things that i would point out:

The first is that, that the spines actually may be leaves

Characteristics: Most cactus are stem succulents; that is, they have fleshy or succulent stems. With the exception of a few tall species and chollas (pronounced CHOY uh), cactuses have no or very little woody tissue. Cactuses native to North America never have leaves on mature growth. Tiny leaves that soon dry up, do sometimes form on the young stems of prickly pear and cholla (Opuntia). Instead, cactus spines are believed to have evolved from leaves. Most cactus cannot remove water from cold soils; therefore winter is the dormant season and summer is a time of active growth.
http://eduscapes.com/nature/cactus/index1.htm

This could mean that such a plant could have simply survived from hungry predators/herbivores by a chance development. Although the inverse could be true for any plant without such defenses. This would require an assumption of what herbivores were around for a few million years and food competition, to allow a theory of 'why spines'.

The second is the DNA, and here I'll add alot of ignorance, but what is the process which forces natural selection at a biochemical level, I get the feeling that it is a bit more than 'survival of the fitest'.... maybe should be another forum.....

thanks for great posts, you two!!!

[Graybeard]

Originally Posted by ScottAnfield I was just wondering if there is such things as intelligent plants. I saw a tree with spikes on it when I was living in Spain http://www.worldofstock.com/closeups/NTR1592.php and my mum told me that it was to stop animals climbing up it to get its fruit. I thought how does a tree know that an animal is climbing up it to get its fruit? It has no eyes to see the animal and no brain to process the fact that an animal is climbing up on it, let alone that an animal is trying to steal its fruit. On top of that, how does it know to grow spikes and how does it know that these spikes will deter animals?

Scott ... the reason you are puzzled and have so many questions is because you are looking at it from the wrong perspective.

A tree doesn't grow thorns with the prior 'thought' or 'intelligence' that the thorns will protect it from 'fruit stealing' fauna. All Flora and Fauna follow the same process. That process works in the following way.

Lets take an easy example, though all adaptations work on the same principle, whether 'artificially' induced or random natural events. I don't know if you have heard of the Samurai Crab or Heike Crab. The following story may be true or not. Carl Sagan used it in his Cosmos film. In any case it serves to show how flora or fauna adapt to meet new circumstance.

In the Battle of Dannoura around 1185 Japan, two powerful clans, the Heike and the Genji, were fighting a civil war over the succession of a seven year old emperor. The final battle between the two clans was fought off the coast of Dannoura, in the Japanese sea. Heike warriors were outnumbered by three to one. They fought bravely. They lost ... in fact the Heike were driven into the sea and either killed or committed ritual suicide.

From the day of the battle crab fisherman in this area would throw back any crab that had markings that resembled a human face as these could possibly be fallen warriors. Over the years crabs with 'human face like' markings flourished and all the others were eaten by the fisherman. Now the gene pool consists of ONLY crabs who have face like markings.

So a change was bought about in the evolution of the crabs through a change in the crabs 'environment'.

This is the same for the Thorn Tree, initially the tree had no thorns, many random, unintentional, mutations occurred in the long evolution of the tree. Accidently something that resembled the beginnings of a thorn occurred in a mutation, a random event, possibly a stunted branch. This was beneficial, it prevented that particular tree's fruit from being stolen to a lesser extent than all the others. The Tree does not know this, but because the trees without this 'thorn' mutation produce less fruit for pollination (theirs is being stolen), eventually, over the eons, descendants of this particular Thorn Tree come to rule the DNA Pool and so from then on all trees produce thorns. Because they are the direct descendants of the first tree to partially develop them, and all other earlier mutations have gone extinct. Now a process of refinement begins, those descendants who accidently mutate sharper thorns pollinate more, so eventually the trees end up with perfect, clustered thorns.

Notice in the illustration how the crabs have come to resemble the Samurai, not just the warriors, as the fisherman become more refined in what they 'select' (consider) to be a fallen warrior

A good overview from the Wiki

Originally Posted by WIKI Overview Life forms reproduce to make offspring. The offspring differs from the parent in minor random ways. If the differences are helpful, the offspring is more likely to survive and reproduce. This means that more offspring in the next generation will have the helpful difference. These differences accumulate resulting in changes within the population. Over time, this process gradually leads to entirely new types of life. This process is responsible for the many diverse life forms in the world today.

Hope this helped ... cool bananas ... greg

[eyeboy]

Greybeard,

Really good answer! I especially liked the simple way man has had an impact on the evolution of that crab in such an unusual way.
Taking ScottAnfield's, DNA concept, a bit further.
I wonder why the DNA would even produce minor differences as some sort of benefit. Is it chance that any species does such a thing. Its almost like genetic material contains some sort of coding for natural selection. what do you think?

[Graybeard]

Originally Posted by eyeboy I wonder why the DNA would even produce minor differences as some sort of benefit.

It does not just produce beneficial ones. For every beneficial it produces billions of irrelevant or detrimental ones. These die out naturally, and quickly, whereas beneficial ones increase there percentage dominance of the population.

It is just spelling mistakes ... A DNA molecule is over 100 million characters long. I don't know if you have ever seen it working as a factory.

A magnified, animated view of it would just show an enzyme plugging in the nucleic acids, rather like assembling/adding each link in a chain. The enzyme reaches out for the first one floating by and attempts to plug it onto the end, if it doesn't fit the enzyme discards it and reaches for the next. Occasionally it plugs in the wrong one .... this could produce an insignificant result, (eg: a few freckles) or a significant result (an overproduction of neural cells, brain increase) Its all just chance. Millions of variations occur all the time, most have no effect in their current environment, some are disastrous such as inherited disease and early death, others are beneficial that enable us to rise a step higher.

Originally Posted by eyeboy Is it chance that any species does such a thing. Its almost like genetic material contains some sort of coding for natural selection. what do you think?

Species themselves are just mutations. Natural Selection just means that of the billions of mistakes produced the beneficial one(s) will rise/ reproduce themselves more often and so come to dominate the DNA pool. They out compete all others and rise to the top.

70 million years ago a mouse like creature called a cylodont produced spelling mistakes in its DNA, as these variations of the cylodont moved into different environments, they became, whales, hippopotamus, kangaroos and us ... all descendents of the cylodont are warm blooded and give birth to live young .....Mammals.

Mammals give birth prematurely (a mistake) and to compensate for this mammals had to invest a lot of time in giving care to their pre-mature young .... bonding developed, emotions, ...... An extreme variation of this led to us. So this spelling mistake became beneficial

Hope that helped .... greg

(If you are really interested and you don't want to read a lot of heavy books on the subject then purchase or borrow the NOVA DVD's on Evolution ... I think there are 4 and they are excellent)