Darwinism Evolution

Lenski’s 40,000 generations of E. coli

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Michael Behe responds on his Amazon.com blog to Richard Lenski’s latest piece in PNAS regarding the evolution of 40,000 generations of E. coli (go here).

[[Patrick and I posted on this simultaneously; please post all comments regarding Behe/Lenski on his thread, which is the the one immediately preceding this one.]]

4 Replies to “Lenski’s 40,000 generations of E. coli

  1. 1
    Bob O'H says:

    and here. 🙂

  2. 2
    DaveScot says:

    I wrote to Mike about Lenski a few days ago and he promised he was going to blog it. Bacteria and fungi adapting/optimizing their digestive enzyme repertoire for any particular substrate in culture is nothing unusual. In fact it can be a problem because when they adapt to one nutrient they tend to “forget” how to digest other stuff. Anyone maintaining commercially important clonal cultures for long periods of time without cryogenic equipment knows about this. Common practice is to vary the agar recipe when reculturing to keep the organism on its toes (so to speak). Senescence is an enemy to keeping valuable strains intact. The only unusual thing about this is that it took years of weekly reculturing for it to adapt to citrate. Weeks or months is a more common period of time to expect to see such things.

  3. 3
    bornagain77 says:

    DaveScot

    As a side light to substrates:

    After reading Behe’s book and seeing the absolute poverty of any truly beneficial mutations to account for the complexity we see in bacteria, I decided to try to investigate ancient/modern bacteria.

    Here is a few articles and papers on the subject:

    “Almost without exception, bacteria isolated from ancient material have proven to closely resemble modern bacteria at both morphological and molecular levels.” Heather Maughan*, C. William Birky Jr., Wayne L. Nicholson, William D. Rosenzweig§ and Russell H. Vreeland ; (The Paradox of the “Ancient” Bacterium Which Contains “Modern” Protein-Coding Genes)

    http://mbe.oxfordjournals.org/...../19/9/1637

    Dr. Cano and his former graduate student Dr. Monica K. Borucki said that they had found slight but significant differences between the DNA of the ancient, amber-sealed Bacillus sphaericus and that of its modern counterpart.

    http://www.sciencemag.org/cgi/...../5213/1060

    http://query.nytimes.com/gst/f.....gewanted=2

    gpuccio and I could find no “fitness test” in Vreeland’s or Cano’s ancient bacteria work, so I wrote Dr. Cano, the researcher of the 25-40 million year old “amber” bacteria and he wrote back saying this:

    We performed such a test, a long time ago, using a panel of substrates (the old gram positive biolog panel) on B. sphaericus. From the results we surmised that the putative “ancient” B. sphaericus isolate was capable of
    utilizing a broader scope of substrates. Additionally, we looked at the fatty acid profile and here, again, the profiles were similar but more diverse in the amber isolate. No antimicrobial panel was used. This is all the data we have and if you want specifics I’ll have to dig through my old notebooks. But it’s there somewhere.

    Take care

    Raul

    Yet when I wrote back asking for more specifics, I received no further reply from him other than for him to say that he was “undecided” as to whether the evidence indicated a gain or loss in complexity for the modern bacteria. I guess he gathered that I was an ID proponent and did not want to get involved (probably ghosts of EXPELLED scared him).

    Whereas
    Dr. Vreeland (250Ma salt bacteria) was a lot less forthcoming with me with any specifics whatsoever, other than to say;

    Dear Mr. Cunningham: The direct answer to your question is no we have not done such a test. In truth any data arising would be meaningless in this instance as it would be impossible to identify the progeny of a bacterium that is 250 million years old and is isolated directly from nature.

    Besides, the tests that you refer to, were dreamed up by Creationists and ID advocates trying to find ways to disprove evolution.

    IMO, Dr. Vreeland is firmly committed to an evolutionary explanation no matter what the evidence would have said and thus I stopped asking him.

    Yet if ID ever gets funding I do think this would be an exceptional and promising area of investigation.

  4. 4

    I presume this is the same Richard Lenski who was involved with the Avida silly business? One of the stated purposes of Avida was to show “how complex functions can originate by random mutation and natural selection.”

    Boy, it seems a lot harder to evolve novel features in real life than it did with that slick computer program! 🙂

    It will be interesting to watch this further and see what they ultimately determine was the source of this new ability. Based on the track record, I’ve got to believe that Behe’s intuition about the insignificance of the result is likely spot on.

    BTW, for those keeping score, Behe is making a real, albeit softly stated, prediction in his Amazon post. We’ll see who ends up being right.

    I particularly love the irony here, as Avida — in my view — inadvertently provided support for Behe’s idea of irreducible complexity. Now e-coli will likely end up demonstrating empirically what Behe has been arguing in Edge of Evolution.

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