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Has a Benficial Addition Mutation been observed?

  1. Jan 5, 2008 #1
    To jump from a single celled organism to a multicellular one, we need beneficial addition mutations in DNA sequences. My question is this: has this phenomena ever been observed?
    By beneficial I mean a mutation in the genotype that serves to cause some phenotype that can be used by an organism in its life processes.
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  3. Jan 5, 2008 #2


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    I'm not sure that I know exactly what you're asking. The impression that I got from the first part was in regard to DNA chains actually gaining base pairs in order to become longer and thus more sophisticated. The second part, though, seems to deal with modifying existing genes. As for the former, I'm pretty sure that it's never been directly observed, although fossil evidence supports it. For it to happen in our lifetimes seems pretty much statistically impossible. After all, our genetic code is almost identical to that of other apes, and something like 90% similar to a sponge.
  4. Jan 6, 2008 #3
    Then doesn't that mean evolutionary theory is out of the realm of science? It cannot be falsified.
  5. Jan 6, 2008 #4
    Examples of a beneficiary mutation is the nylon bug or antibiotic resistant bacteria. More examples here and here.

    Evolution is certainly falsifiable:

    - Show that the earth is < 6000 (or any other low age) and evolution is false, because there is not enough time for it to happen.
    - Date human fossils to the same age as T-Rex fossils; common ancestry as we know it is false.
    - Find chimera organisms, that is, organism with parts from different lineages.
    - Static fossil record.
    - Find a mechanism that would prevent mutations from accumulating.
    - Observe organisms being created.
    - Repeat an experiment that is used to support evolution and show that the result is actually negative.

    Last edited: Jan 6, 2008
  6. Jan 7, 2008 #5
    Ummm...unless I am misunderstanding the question, this is observed all the time.

    Go to PubMed and you should be able to search through thousands of fitness experiments where just this type of thing is studied.

    You change an organism's environment (light, heat, food, etc.) and observe the results at various time-points, sequence the DNA of the survivors, and record any differences that occur within the gene/genes of interest.
  7. Jan 7, 2008 #6


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    But are these deletion mutations or the silencing of a bit of information rather than the formation of new genetic material and the formation of new information in the genome?

    I would argue that there is ample evidence and an appropriate theory for the genesis of new DNA and the formation of new genetic material. It happens when we get sick.

    Could the virus be the ultimate agent of change? Could the discussion of punctuated equilibrium and the like merely be manifestations of the temporal non-linear nature of pandemics to effect that change?
  8. Jan 7, 2008 #7


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    I might agree with you if I knew what the hell you're talking about. KISDID Principle, please (Keep It Simple Dude, I'm Drunk). :tongue:
    I've never heard of 'punctuated equilibrium', other than once rupturing a rubber. Are you suggesting that all genetic change is initialized by viruses? I can't argue that none are, but attributing everything to that seems a bit narrow. What about other mutagenic factors such as radiation or chemical exposure?
  9. Jan 7, 2008 #8
    Of course. Some of the best known are bacteria which develop the ability to digest new substances. This known to have happened on several occasions. Another very well known example is bacterial drug resistance and insect insecticide resistance.
  10. Jan 8, 2008 #9
    An event that could have produced what we now call the geological time column can be modeled on the May 18th, 1980, Mount St.Helens eruption and the consequential material deposition.
  11. Jan 8, 2008 #10
    No, it can't. For a variety of reasons. For instance, Coarse grained igneous rocks require millions of years of cooling in order to get there structure. Eruptions like MSH only produce mircograined rocks. Any ametur geologist can tell the difference between a volcanic rock and a rock formed under different conditions which means that vulcanism cannot replacate the other's formation methods. Certain layered rocks require regular cyclic conditions in order to form. Amoung those are ones which are solidified versions of layers that we observe to be layed down in seasonal patterns today. It's far more logical to assume that the same seasonal cycles layed down these ancient layers than to assume an entirely new system that is not observed, works entirely differently, and yet has exactly the same effect.

    I'm sure I can come up with more examples, but the bottom line here is that a rock contains tremendous amounts of information about its history, and a skilled geologist who carefully examines a rock can learn a great deal about its history (not just how old it is.. which is relatively easy)

    Just to add something else, there are those that suggest that the grand canyon was made by some sort of flood. In fact, floods can form canyons, and such a thing happened, forming the Grand Coulee. However, examination of that structure makes it obvious that it was formed by a flood, while examination of the grand canyon shows that the similarity between the two is only superficial. Examination of a structure requires going and seeing what is there, not just looking at postcard photos. The differences then become obvious.
  12. Jan 8, 2008 #11


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    One thing evolutionary theory is NOT, is simple. (If it were, a lot more people would be able to believe in it.)
    You'd better bone up on the subject then.

    Punctuated equilibrium is The modern, generally accepted dynamic of evolution. It's the biggest place where our current understanding of evolution deviates from Darwin's, and no discussion of evolution can really go far without it.

    In a nutshell, Darwin thought species evolved slowly and continually from gen to gen. Punctuated Evolution proposes that evolution happens in short bursts separated by long periods of equilibrium. Among other things it explains why we see relatively many identical examples of a species in the fossil record and relatively few transitional examples of species.
    Last edited: Jan 8, 2008
  13. Jan 8, 2008 #12
    That *IS* evolution. What yooure telling me sounds akin to "There is no such thing as an airpalne. They are just cars with wings that can fly."
  14. Jan 8, 2008 #13


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    :rofl: Man, if ever we needed a 'groan' smilie, this is it.

    Okay, I'm familiar with 'punctuated equilibrium' as an approach to understanding evolution; I've just never heard that particular term for it. Sorry for the misunderstanding.

    Lewis, I'm going to ask you one very serious question before this thread gets locked. If you're so certain that some sort of supreme being created everything... who created god? It couldn't have just popped up on its own now, could it?
  15. Jan 8, 2008 #14
    This sentence shows a fundamentally incorrect view of what is in "the realm of science." Plenty of things in science can't be falsified. In fact, something is considered a theory because all the evidence supports it, but in the end it can't be falsified.

    Read up on the difference between hypothesis, theory and law for a better explanation.
  16. Jan 8, 2008 #15

    Actually all of the above can happen. The most common change one sees is just a SNP (Single Nucleotide Polymorphism) in which just one base is changed. Depending on where this change is, it may change the amino acid that is present in that position of the protein...and may change the function of the protein itself.

    Deletions or insertions may also happen, but this is NOT insignificant. If one base in a gene is either deleted or inserted, it causes a reading frame-shift. A frame shift will change EVERY amino acid downstream of where the deletion or insertion took place. This would drastically change the protein.

    In terms of evolution, other types of changes may also occur such as transopsons, gene duplications, or (as you stated) a virus can deposit it's genetic information into a genome. In addition you can have alternative splice forms of a protein where the gene may be the same, but it is put together differently. Some simple life forms also may trade genetic information.......I could go on and on.

    I really don't see how people can think that genetic change does not happen....the evidence is overwhelming.

    On a side note: Danger, you are one brave soul to venture these forums drunk! LOL :P
    Last edited: Jan 8, 2008
  17. Jan 8, 2008 #16


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    That's about the only way that I ever venture here. Why did you think that most of my posts don't make sense?
  18. Jan 8, 2008 #17


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    I've said more than once that the probability of life starting with viruses is (probably) high. Whether they transmigrated here or were formed here is another question.

    It is true that you will see beneficial mutation in VRNA and VDNA. The sequences can expand rather suddenly. I imagine, because a virus can only reproduce using a host cell and host DNA (these days), that the VRNA or VDNA will pick up strands from its hosts... then utilize what is useful to further its... survival.

    Here's a free article on the subject

    Last edited: Jan 8, 2008
  19. Jan 8, 2008 #18


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    Cool. I can't concentrate on it right now, what with clients showing up every couple of minutes, but I'll definitely check it out later.
  20. Jan 8, 2008 #19


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    Lewis is waaay wrong, but that isn't really correct either. Testability and falsifiability are roughly synonomous. For theory that can be tested in a lab with experiments, failing a test can provide falsification. With evolution, finding contrary evidence is where falsifiability comes in. If a genuine, fully-formed human were found fossilized next to a dinosaur (and people believed it), that would provide falsification of evolution.
  21. Jan 8, 2008 #20
    Sure. There are lots of ways to falsify evolution. Another example: Sometimes, as a random mutation, creatures display features of their evolutionary anscestors (humans born with tails, whales and snakes with legs, etc). Now, by evolution, the only features that can be exhibited by such atavisms are those of a creature's direct evolutionary anscestors. So, for example, since humans are not descended from insects, a human born with insect parts would be a serious blow to our understanding of evolution.
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