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Is natural selection driven by intelligence?

  1. Mar 23, 2006 #1
    First of all I want to make clear that this topic isnt about ID.

    On wikipedia I read this definition of NS:

    Not too long ago I saw this story about intelligent bacteria:

    Further down the article u can read how bacteria behave and 'help' eachother out in different situations, some even sacrifice themselves by committing suicide.

    So is natural selection driven by intelligence?
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  3. Mar 23, 2006 #2


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    At first it was pure luck I suppose, but with time and introduction of a nervous system, it was with the aid of memory, cognitive function, and behaviour. I suppose when it comes to vertebrates, you bet your spinal cord its driven by intelligence.
  4. Mar 23, 2006 #3
    With "at first", do u mean prior to organisms having a nervous system?
    Do the microbes from the article in my first post have a nervous system?
  5. Mar 23, 2006 #4
    Part of the problem is the idea of intelligence.

    How are you defining it here?

    Bacteria can be conditioned, and they respond to envornmental cues, but these behaviors appear to be down to signal transduction pathways and no one would seriously consider these behaviors to be evidence of intelligence. A leaf wilts when there is insufficient water (this phenomenon has been selected for and is the "smart" thing for the leaf to do), but the wilting is due to lowering osmotic pressure - not intelligence unless you are playing with semantics.
  6. Mar 24, 2006 #5
    Well one definition that stuck in my mind was something like "problemsolving ability".
    This is also what i was reminded of when reading this part of the definition of NS:

    "their ability to tackle the challenges posed by their biological and physical environment"

    So yes, im using intelligence in a very broad sense here. If an organism can solve certain problems, then it is intelligent. It basically selects itself simply by being so intelligent that it or its companions survive and reproduce.

    I got a different impression from reading the article about bacteria in my first post.
    Sections like these seemed to indicate they were intelligent in some sense:

  7. Mar 24, 2006 #6


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    Communication in that last quote just means the exchange of some chemical or other. All this is chemistry and the steps are on the way to being well pinned down. Many computer systems are as "intelligent" as that. They can communicate and they can change their states based on that communication; that's all that's implied for the bacteria.
  8. Mar 24, 2006 #7
    Sure the steps may one day be pinned down. Does that mean they arent intelligent?
    Or if they figure out how to build AI, does that make the bacteria unintelligent or the computer intelligent?
  9. Mar 24, 2006 #8


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    Evolution actually favors the "left wall of simplicity." Bacteria are arguably much better adapted to life on Earth than are humans -- they're simple, reproduce very rapidly, and can adapt to an enormous range of physical and chemical environments.

    Humans, on the other hand, are fragile and can only live within a narrow range of environments.

    Far from favoring intelligence, evolution actually favors simplicity. Intelligence only evolved out of necessity.

    - Warren
  10. Mar 24, 2006 #9
    All that means is that the intelligence doesnt necesarily result in more and more intelligent individuals.
    It doesnt mean the selection isnt driven by simple, rudimentary intelligence.
  11. Mar 24, 2006 #10
    Intelligent creatures certainly evolve faster. Look at, for instance, small birds, who have high ratios of brain to body weight. Currently, the mechanism behind this is assumed to be the greater flexibility of intelligent life. Imagine a stupid bird that could peck at grubs half-exposed in wood, but was descended from a line that caught insects on the wing. How many generations would it take for the behavior of grabbing at grubs take to appear and allow natural selection to start adapting the bird to that task? A smart bird, on the other hand, would teach itself the behavior, and continue to exploit new adaptations more fully.
  12. Mar 24, 2006 #11


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    Well what you CALL things is up to you!:biggrin:

    I personally find that there is something in the cognitive abilities of the hominids (and perhaps limited to genus homo) that is distinctly different from the capabilties of all other terrretrial organisms, and it seems problematical to me to blur this distinction so far that very simple "mechanical" systems are counted as intelligent. What's next, thermostats?
  13. Mar 24, 2006 #12
    A quick look at any textbook on evolution will clarify that natural selection = the differential (nonrandom) reproduction and survival of genotypes. If, as suggested above, we define intelligence as "problem solving", it is clear that the general process of natural selection does not require intelligence. A simple example--female fruitfly "A" produces 23.6 eggs when environment is at 25 C, female fruitfly "B" produces 6.5 eggs. There is no problem to solve--type A female genotypes would quickly replace type B over time, all else being equal. Clearly, those forms of life with intelligence can alter outcome of selection process--but natural selection does not require intelligence, it requires genes in interaction with an environment (biotic and abiotic).
  14. Mar 25, 2006 #13
    There is something quite different about it indeed. But if we follow the evolution of intelligence back in time, can anyone really say where it started and how? Or are we then in the domain of the origin of life?

    True, but i still wonder if that isnt some kind of 'rudimentary intelligence'. Changing the reproduction rate in response to stimuli is somewhat similar to what is described in this article about bacteria:

    So while it may seem simply like temperature increased their output instead of any intelligence, there is still some process inside the organism involved in doing this and it could qualify as an extremely simple form of intelligence.
    Last edited: Mar 25, 2006
  15. Mar 25, 2006 #14
    Its going to be hard to measure intelligence without an IQ test... I don't think microbes have access to computers or pencils to take the test.

    It is interesting that, in the chromosomes of the cells of tissues in humans there is a gene that is called the P52 gene. This gene, through natural selection, has a design that would seem to be altruistic in that it is the cell regulator and decides if the cell will live or die. If the cell becomes mutated or infected, P52 decides the cell and all its organelle should commit suicide to save the surrounding cells from infection or mutation... (such as cancer).

    However, there is a mutation, (cancer) that can shut off the P52 cell. And that is what we see today when we see a tumour. It is a result of the mutation that is cancer's ability to shut of the P52 gene's ability and mandate to cause apoptosis and continue to grow, damaging the surrounding tissues, structures and various leukiocytes.

    The advent of the P52 gene is probably a result of the drive for suvival in the integrated cells of a tissue brought about by natural selection.

    The function of the P52 gene is no doubt an autonomic one and not a result of intellegent choice. It is probable that similar, autonomic mechanisms have developed in single celled microbes as well and that they are not intelligent choices but are naturally selected features that lend themselves to survival.

    Have a look at the diagram on this page discussing neuronal cell death. The design looks completely intellegent but is the result of trial and error... or natural selection.

    Last edited: Mar 25, 2006
  16. Mar 25, 2006 #15
    Im curious, do all living cells have such genes for autonomic mechanisms?

    If so, then it moves their origin outside the scope of NS.
    If not then they would be naturally selected.
  17. Mar 25, 2006 #16
    Before I take a stab at answering your question I want to point out the bacterial that live in a symbiotic relationship with the Lichen plant.

    The Lichen obtain nutrients secreted by the microbes and the microbes obtain shelter and nutrients from the Lichen. The arrangement came together probably by accident. There was no Intelligent decision made by either organism to come together and create the symbiotic relationship.

    Genes may have developed that supported this relationship because of the proximity and the relative support found in the relationship. The genes would support certain functions that resulted from the symbiosis.

    This is how genes are formed (to answer your query). They come about to maintain a function or process as well as hang on to that function as a genetically transferable trait to offspring (hence survival of the species) that has been introduced.

    This is all about Natural Selection. You have trillions of genetic combinations in each cell that no longer apply to that cell because it has become specialized. The most striking evidence of this is seen in developing human foetuses. During one stage of development we have gills and we really look like a fish then an amphibian. These are gene expressions that are superceded by newer, compiled gene sequences that direct our development toward the latest mode of selection and survival... the human morphology... which is dictated by the latest selection of genes.

    And our modern set of genes seems to have worked in terms of a good selection for survival since, as you can see, we have just reached the 6 billion mark in terms of populating the planet.

    But, the genes were not intelligently selected by the cells themselves... they are selected by a process not unlike following the path of least resistance (like the path a rock takes when rolling down a hill) ... the "dominant genes" are a result of natural selection... or "trial and error".
    Last edited: Mar 25, 2006
  18. Mar 25, 2006 #17
    So it is the 'function' or 'process' which keeps the genes of value and transfers them to offspring. And it is this function or process which i say may be a form of intelligence.

    Its actually quite simple. Ive twisted 'survival of the fittest' into 'survival of the most intelligent', because fitness can be considered a form of intelligence ('physical intelligence', like there is also 'emotional intelligence' :biggrin: )

    Following the path of least resistance doesnt imply that the genes are beneficial for survival, so that itself isnt what selects the genes which are passed on. A thousand paths of less resistance can be followed and all be doomed, but the one that isnt doomed is the one that serves the function needed for survival.

    And as for this part:

    Is this what they call symbiogenesis?
    And if so, then isnt that a form of cooperation? At least thats what i read on wikipedia:

    Last edited: Mar 25, 2006
  19. Mar 25, 2006 #18
    It is the competition with the environment that selects a gene to be expressed and expressedly selected to express in subsequent offspring. The gene is produced in response to the organism's environment... not by choice but rather by "accident" out of the "inate instinct" to survive.

    Whomever is using the word "intelligence" to describe the selection and expression of genes and symbiotics is out of line by my dictionary.

    Web Dictionary:
    Certainly microbes profit from experience but, as i've pointed out earlier, until you can manufacture a computer or pencil that suits their scale, then get them to write an IQ test (intelligence quotent) you cannot tell me they are making intelligent choices, comprehending or understanding their predicament(s), nor, like an intelligent organism would do, can they relate their understanding of their experience to us.

    This smacks of a defence for Intelligent Design... even though you have written that it has nothing to do with the topic. Have a good weekend.
  20. Mar 25, 2006 #19
    Carl: I didn't read your whole response, but lichens are algae and fungi. Bacteria are not part of lichens.
  21. Mar 26, 2006 #20
    Here u talk of 'competition', 'response to environment' and 'inate instinct'. It is these things which i here label a form of intelligence. Im not introducing anything new.

    I dont think the IQ test should be the universal indicator for intelligence. But i completely agree that it is counterintuitive to see microbes and other simpler animals as intelligent.

    I would say: if all life is intelligent, then natural selection is driven by it.
    If not, then NS cant be driven by it.

    It actually has nothing to do with ID, its the same old NS were all familiar with. No irreducibly complex systems, no non-random mutations.
    Last edited: Mar 26, 2006
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