Update on E. coli long term experiment

Interesting update on the long term E. Colin experiment.

It appears that new insights are coming about regarding evolution as they continue to evolve to better fit their environment. While some thought evolutionary change would slow, evidently it continues despite a static environment. Seems the little bugs just don’t give up in their quest to improve.
It will be interesting to read about how they are still E. coli in the ENV and YEC press. (Sarcasm)

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Still reminds me of that superhero in “Mystery Men”, that could turn invisible, so long as no one was watching.

So the equivalent of roughly 1,000,000 years of human or cetacean evolution, when actually observed scientifically, shows nothing comparable to the leaps in complexity demonstrated in equivalent generations in these other organisms?

It will be interesting to read how the actually observed phenomena have no relevance to those species we can’t observe over longer periods as that would be comparing apples to oranges… (sarcasm?)

Are they not still e. coli?

Indeed they are, I was just reflecting on how often that phrase has been used in the past, and how it would be thrown out again. Now, if the experiment is expanded to a diverse range of environments, and goes on for a thousand years or so, it would be interesting to know if they were still E. coli. As it is, the environmental constraints help focus on a more manageable number of observations.

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Okay, so amateur question time…how big is it that the population that evolved to process a new food source? Is this roughly equivalent to a human population that can eat bark? Or, is it more like eating hemlock and not suffering the side effects? Or, is there no real comparison? I ask because it seems, my untrained eye, that developing the ability to process a food is starting to gray that line defining ‘still e-coli.’ Thanks for taking to time to explain!

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“Equivalent” in what way, exactly? These bacteria are in a static environment and there is no recombination possible. Hardly equivalent - both of these factors are major ones for shaping adaptation.

Not surprising, given the above.

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Would you be so kind as to provide references to the “leaps of complexity” that have occurred in the last million years of human evolution?

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Natura non facit saltum

While the news article made that comment regarding the million years, I would say that is a serious misrepresentation. After all, E. coli themselves are the product of millions or billions of years of evolution. The writer of the article was conflating numbers of generations with time, which is not the same. It is sort of like saying a millipede walking a foot across the floor is the same a a human running a marathon. The number of steps may be the same, but they are quite different things despite the common factors.

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For that you’d have to address the linked article, it was the author thereof that made said claim.

Ah, yes, of course. But as I mentioned, It will be interesting to read how the actually observed phenomena have no relevance to those species we can’t observe over longer periods as that would be comparing apples to oranges…

:wink:

In so far as the results are transferable to other organisms, it’s perfectly relevant. But bacteria aren’t mammals, and the differences matter (mostly things like recombination through sex, a changing environment, predation, and so on).

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Yes… please! what are the leaps of complexity in our human ancestors over the past 1 million years? … well… other than the evolution of WASP creationists and their incredibly complex justifications of assertions contrary to the objective evidence.

Translation: “Nature does not make leaps”. Saltum can also be translated '“jumps”, but what is a synonym between friends?

Is it really equivalent? The e. Coli did not have a million years of radiation exposure.

23 OCT 2017, Got anything more recent?

So far, I believe, there have been no particular surprises for the YEC or ID communities. Let me know if something interesting happens.

Thanks, Professor Lenski, the LTEE Is Doing Great!

Michael Behe, March 29, 2019, 4:18 AM

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The LTEE has surprised anyone who contends that natural selection is unimportant.

The LTEE has in principle surprised Behe, who contended in 1999 for a genetic definition of irreducible complexity based on the number of neutral mutations. (The LTEE has demonstrated important phenotypic changes resulting from a single activating mutation preceded by several neutral mutations.)

The LTEE has surprised anyone who thought that evolutionary dynamics were unimportant.

If your definition of surprise is based on the expectation that 20 years of test tube evolution would not permit a tiny population of E. Coli to become mammals, then yes, you can profess not to be surprised. Just bear in mind that evolutionary biologists are not surprised either.

Best,
Chris

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That has got to be the biggest understatement I have heard in my entire life. LOL

I can’t think of a great analogy in human terms, so (for me, at least) a comparison is difficult. E. coli has the enzymatic capacity for anaerobic citrate utilization, but it typically only does it under anaerobic conditions.When biochemically testing for E. coli, aerobic citrate utilization is a common test. The citrate in the culture medium was added only as a chelating agent, without the expectation for citrate utilization genes to alter. However, one particular sample in the LTEE started utilizing citrate under aerobic conditions. A lot of YEC and ID yawn at it because “it is still E. coli!”, but others have at least asked the question “Is it really still E. coli if a fundamental identification test no longer indicates that it is E. coli?”

The biochemical capabilities of this particular strain didn’t change dramatically, but the expression of the involved genes did. It is certainly fascinating (particularly the main mutation that allowed this), and although I consider it a pretty big deal, it isn’t as dramatic as developing an entirely new set of genes allowing metabolism of a completely new food source (the article is probably a bit misleading).

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@jpm Phil j
The Lenski e. coli experiment clearly demonstrates according to the researcher quoted in the article that environment guide evolution, which is what I have argued also based on this experiment and other studies. I really do not know why people at BioLogos can’t agree with the available evidence as to how natural selection works.

That very well may be the case. But it strikes me still… a bit convenient. Macroevolution conveniently only happens at scales beyond our ability to observe, and that scale conveniently shifts just as needed to exceed our ability to observe. Hence why it strikes me as like the superhero in Mystery Men that could turn invisible so long as no one was watching.

We’d have to watch hominids or cetaceans over a few million generations to actually observe the undirected evolutionary process develop the significant new complexity involved.”

“But we can conceivably observe bacteria, or perhaps some Protozoa, for a few million generations over the course of a few human generations…”

“No, for those we have a special scale… we would need to watch those organisms for a trillion generations before we could observe any similar increase in complexity.”

Hi Roger,

I’ve read the long, long, long, long threads and come to the conclusion that you have misunderstood “the people of Biologos” on this issue. Other than that, I agree with your post.

Best,
Chris

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