The creationists are gonna freak!

Patsy said:
I can't imagine this will freak them out any more than everything else does.

Rational Person: Here is a large stack of scientific evidence that clearly shows your assertion the world is only 6000 years old is mistaken.

Creationist: I'm being persecuted! You hate Christians! It's a conspiracy!

RP: I think that only science should be taught in science classes. Religious and other values should be passed on at home in the family.

C: I'm being persecuted! You hate Christians! It's a conspiracy!

RP: Evolution has actually been observed in the laboratory.

C: I'm being persecuted! You hate Christians! It's a conspiracy.

No need to even change the script to handle this new information :D
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From a real, non-parody point of view, they do manage to ignore the nylonase mutation in bacteria, so I agree, this will not be a hurdle for them.
 
shadron said:
Are you sure that wasn't from Mel Brooks?
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You know, I'm amazed you've said just this! Just the other day I was looking at a Mel Brooks two 'fer movie pack...

It must be my inner Indigo child!

:D
 
OK, now, I have a philosophical question about this.

A while back, in a thread about SETI, The Atheist was citing the SETI program as borderline woo, because it is essentially an non-falsifiable experiment - actually he was railing about its cost, and this woo conjecture was a (semi-serious?) result. The SETI hypothesis, I imagine, can be expressed as "we think there are others out there", and they proceed to look, but no matter how hard they look, they won't ever be able to say, "Well, there must be none, because we have no positive results". While I don't agree with TA's conclusions, this presentation did make me stop and ponder a bit about the philosophy of the SETI project (hooray for the forum; at the very least, I'm entertained and find, surprising myself, that I can change opinions!).

Now we have Lenski's experiment. Very ambitious, and, in this case, very successful, or at least fraught with new lines of investigation, which is usually a sign of the same thing. I don't know what the object ("hypothesis") of the original experiment was, but I doubt it was to prove anything like the results we see here (or did it? Looking at the paper, they jump right into the citrate transport problem as if that was what they were hoping to see evolve from he first. Is that true?) I see philosophical parallels between SETI and Lenski's cultures, and I'm wondering how they should be regarded as science. I know of any number of experiments in which an instrument is built to observe some rare, perchance never occurring statistical event; is that essentially different from SETI?

Feel free to enlighten a dull engineer, if you please.
 
Jimbo07 said:
You know, I'm amazed you've said just this! Just the other day I was looking at a Mel Brooks two 'fer movie pack...

It must be my inner Indigo child!

:D
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My teenaged kids have played all his movies so often that they are pretty much imprinted on my mind. When I was in college, one of the favorite pastimes among the theatre people (I was one of them, while pursuing physics) was dropping quotes from the play du jour into the conversaion, and I haven't been able to loose the knack, try as I might.

I was thinking of History of the World Part II, though the line also contained a lot of "bs, bs, bs...".
 
shadron said:
OK, now, I have a philosophical question about this.

A while back, in a thread about SETI, The Atheist was citing the SETI program as borderline woo, because it is essentially an non-falsifiable experiment - actually he was railing about its cost, and this woo conjecture was a (semi-serious?) result. The SETI hypothesis, I imagine, can be expressed as "we think there are others out there", and they proceed to look, but no matter how hard they look, they won't ever be able to say, "Well, there must be none, because we have no positive results". While I don't agree with TA's conclusions, this presentation did make me stop and ponder a bit about the philosophy of the SETI project (hooray for the forum; at the very least, I'm entertained and find, surprising myself, that I can change opinions!).

Now we have Lenski's experiment. Very ambitious, and, in this case, very successful, or at least fraught with new lines of investigation, which is usually a sign of the same thing. I don't know what the object ("hypothesis") of the original experiment was, but I doubt it was to prove anything like the results we see here (or did it? Looking at the paper, they jump right into the citrate transport problem as if that was what they were hoping to see evolve from he first. Is that true?) I see philosophical parallels between SETI and Lenski's cultures, and I'm wondering how they should be regarded as science. I know of any number of experiments in which an instrument is built to observe some rare, perchance never occurring statistical event; is that essentially different from SETI?

Feel free to enlighten a dull engineer, if you please.
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Since you've decided to take after one of the great web surfers (me) :D let me show you how the investigation is done.

I noticed the paper did say what the original problem was, I just wasn't familiar with the term, "historical contingency". I suspect you missed it as well.
The role of historical contingency in evolution has been much debated, but rarely tested. Twelve initially identical populations of Escherichia coli were founded in 1988 to investigate this issue.
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And since Lenski seemed to be mentioned more than the other authors, I just Googled, "Richard E. Lenski historical contingency". Then I opened the first few links that weren't just hits off the abstract. And I found the answer. [This search took 3 minutes, she joked after the Google acknowledgment they give themselves with every search. :)]

This link from Panda's Thumb had a clear answer.

Historical contingency in the evolution of E. coli
What Blount et al. are doing is testing SJ Gould's old claim that if we replayed the tape of life, we would not get the same results each time. Each step in evolution is dependent on prior history — it is contingent — and since many of the steps are driven by chance yet unfiltered by selection, we cannot predict the direction of evolution.

We can't rewind the whole planet, but with careful design, we can set up populations that can be rewound. Lenski has done this by setting aside 12 separate populations of E. coli 20 years ago, each one evolving independently and in its own direction. So far, over 44,000 generations have passed in the flasks in Lenski's lab. This is a long time, and at the typical mutation rates present in these creatures, it means that every nucleotide has been mutated singly multiple times in the population — in other words, there has been ample time to thoroughly explore the single substitution search space. In addition, a sample of each population was taken and frozen every 500 generations, so they can go back in time at will and examine their genome or even restart the line. Imagine what we could learn if some ambiguously benevolent space aliens had visited the earth every 5-10,000 years, snatched up a couple of random hominin/primate tribes, and had them tucked away in cryogenic storage — that's what this experiment is like.
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It's an excellent discussion and worth a look anyway.
 
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I love Panda's Thumb's comment on Behe's comments.
Wait a minute — has he read the paper? This is an experiment that revealed a trait that required at least three mutations. Yet there it is, produced by natural evolution, with no intelligent design required; and when the experiment is re-run with populations that had the initial enabling variant, they re-evolved the ability multiple times. It seems to me that this work demonstrates that drift, chance, historical contingency, and selection are sufficient to overcome his "big evolutionary problem", and directly refute the premise of his book.
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It's so obvious to everyone except Behe.
 
skeptigirl said:
Since you've decided to take after one of the great web surfers (me) :D let me show you how the investigation is done.
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Hey, one has to learn from the masters... ;)

I noticed the paper did say what the original problem was, I just wasn't familiar with the term, "historical contingency". I suspect you missed it as well.And since Lenski seemed to be mentioned more than the other authors, I just Googled, "Richard E. Lenski historical contingency". Then I opened the first few links that weren't just hits off the abstract. And I found the answer. [This search took 3 minutes, she joked after the Google acknowledgment they give themselves with every search. :)]

This link from Panda's Thumb had a clear answer.

Historical contingency in the evolution of E. coli

It's an excellent discussion and worth a look anyway.
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Thanks for that; I'll read it. So, they weren't looking for anything in particular, just proof that contingency works as Gould said it would. I guess thay found proof with a vengence, then.
 
shadron said:
Now we have Lenski's experiment. Very ambitious, and, in this case, very successful, or at least fraught with new lines of investigation, which is usually a sign of the same thing. I don't know what the object ("hypothesis") of the original experiment was, but I doubt it was to prove anything like the results we see here (or did it? Looking at the paper, they jump right into the citrate transport problem as if that was what they were hoping to see evolve from the first. Is that true?)
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There's no other reason I can see for including citrate in the feed. E Coli is apparently known for its inability to metabolise citrate. This is what the scientists involved have been waiting for these past twenty years. It's a beautifully designed experiment. Hopefully it's not the only one started back in "the old days".
 
Apparently they'd thought that citrate metabolism was a possible bonus, but not explicitly what they were looking for. From the link skeptigirl gave in post 28, (scroll down to read post 115).

What is the citrate doing there? Well, it is part of the DM25 recipe, and has been since it was first reported by Bernard Davis and Elizabeth Mingioli in 1950 (Davis and Mingioli 1950. Mutants of Escherichia coli requiring methionine or vitamin B12. Journal of Bacteriology 60(1): 17 - 28.). They included it for two reasons. First, E. coli use something called the ferric di-citrate iron acquisition system to take up iron from their environment, though in this system, the citrate never enters the cell (see Hussein, S., Hantke, K., and Braun, V. 1981. Citrate-dependent iron transport system in Escherichia coli K-12. European Journal of Biochemistry, 117: 431 � 437.). While E. coli have another set of genes for what are called enterochelins, which can also be used for iron acquisition, citrate is commonly included in defined E. coli growth media (defined media are growth media for which we known exactly what is there and in what amount, as opposed to rich media such as Luria broth, trypticase soy broth, or brain heart infusion, which include enzymatic digests of yeasts and various proteins and, yes in the case of the third one, brains and hearts of cows which can vary in their exact constituents) just to make sure that the bacteria don't starve for iron. Also, when the media from which DM25 was developed were first formulated in the early to mid-20th century, it was common to keep them in 50x stocks that were then later diluted with water before use. At this concentration, the sodium citrate concentration was increased beyond what the organism strictly needed to prevent another component of the medium, magnesium sulfate, from precipitating out. As E. coli were not bothered by this, no other thought was given to the issue.
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Great experiment. Seriously, great experiment. Another nail in the coffin of ID. You'd think there were enough by now, but we can keep putting more in. :)
 
Mashuna said:
Apparently they'd thought that citrate metabolism was a possible bonus, but not explicitly what they were looking for. From the link skeptigirl gave in post 28, (scroll down to read post 115).
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I'll take your word for it (and thanks); there's another reason for the citrate that I can now see. It's a necessary resource, but not as a food item.

Notice how that "possible bonus" seems to have paid out?
 
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