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Hard Evidence for Evolution

  1. Apr 1, 2013 #1
    I have read several posts asserting that mutation and natural selection cannot add complexity or useful functions to the genome.

    I'd like to add a link to an experiment that proves them wrong, and also teaches us a lot about how evolution works - the E-coli long term evolution experiment.


    What is interesting is that it disproves several assertations I have seen made by creations, namely

    1. Evolution has never been observed in the lab - clearly it has, from this link.

    2. Evolution does not add new functionality, it merely shifts around the existing - again disproved soundly by the link

    All in all, a fascinating experiment which should be more widely known.
    Last edited by a moderator: Apr 1, 2013
  2. jcsd
  3. Apr 1, 2013 #2
    i dunno if complexity and extra info can be considered the end point of evolution, which is survival. For example with a few exceptions, when bacteria antibiotic resistance is gained, a bacteria usually loses some of its virulence and becomes a little weak. That still counts as an evolution example right?
  4. Apr 1, 2013 #3


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    Joe Thornton at the University of Oregon has also done some very interesting work studying the evolution of various protein families and has been able to determine the molecular mechanisms that allow organisms to evolve new functions. For example, he has done work to study how an ancient steroid receptor underwent gene duplication and subsequent mutation to become a receptor for a new steroid molecule (Bridgham et al. 2006. Evolution of Hormone-Receptor Complexity by Molecular Exploitation. Science 312: 97. doi:10.1126/science.1123348). In more recent work, he studied how mutations allowed a simple molecular motor protein in yeast to evolve into a more complex motor protein (Finnigan et al. 2012. Evolution of increased complexity in a molecular machine. Nature 481: 360. http://dx.doi.org/10.1038/nature10724 [Broken]).

    If there's more interest, perhaps I'll make an expanded post on this topic.
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  5. Apr 1, 2013 #4


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    Nice study, and I appreciate you posting it here. I don't need convincing myself, but I wanted to give you a quick reality check - this is unlikely to convert the doggedly convinced.

    I'm a microbiologist and an atheist. Of course, I see the evidence for bacterial evolution in my lab on a daily basis. I accept that this same process acting on the entire biosphere for much longer periods of time has given rise to the incredible diversity of life on the planet, including humans. So there's no need to convince me.

    But I have a friend, who's also a microbiologist (a more senior colleague). More than that, his expertise is the evolution is antimicrobial resistance, considered a prominent international authority, published in Nature Genetics and what-not. However, he's also a Christian. He believes God created everything, and especially humans in his own image. He's able to reconcile this apparent contradiction by making an arbitrary (to me and most scientists) distinction between "micro-evolution", "macro-evolution" and "speciation". He does not believe that different species (certainly not different species of multicellular creatures) arose from the same evolutionary process that operates to cause bacterial diversity.

    I disagree with him (of course), but I'm highlighting this to show how powerful dogma can be. This is his special area of scientific expertise yet he takes a very narrowly circumscribed view of the topic in order to avoid conflict with his religious beliefs.

    If that's the level of resistance you can expect from some scientists who work in this very area, imagine the level of skepticism you can expect from the lay public, and indeed the very Creationists you are attempting to convince. Unless you can accelerate evolution to the point where you see those bacterial colonies transforming into, say, a cat (I'm being facetious, of course), you're really not going to convince anyone. And that saddens me.
  6. Apr 1, 2013 #5
    To follow up Mr. Curious here, most of the biologists in other countries, in Asia, Africa or the middle east can put aside their beliefs and not have it conflict with their work. So why is there such controversy in this country.
  7. Apr 2, 2013 #6


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    Sorry, your friend simply isn't an expert on evolution if he considers "micro" and "macro" evolution two different things.

    And frankly, my poe meter is pinging.
  8. Apr 2, 2013 #7


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    Yes evolution has been shown to be true time and time again. The LTEE results represent just one piece of the mountain of evidence. This isn't debated by anyone but creationists for poor reasons, as this thread is mainly focused on this non-debate there is no need for it to continue.
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