Ready, set, mutate... and may the best microbe win

Rice University ^ | 18 May 2006 | Staff (press release)

[Dimensio]

Interesting. It looks like an evolution "closed loop". It is as though the program (DNA) is designed to cope with certain conditions - "when this happens, do this".

I do not understand the means by which you derived this conclusion. Your conclusion would be appropriate if mutations toward better survivability occured following a change in environmental conditions, however that is not the case here. The mutations occured first, and then environmental conditions were changed in a way that caused all but a subset of the varied population to die off. There is no indication that the DNA itself changed in response to environmental conditions, as you suggest.

[RobRoy]

The mutations are there, hanging around - just in case. It is a way of "hedging bets". Stay loose and diverse.

[Dimensio]

The mutations are there, hanging around - just in case. It is a way of "hedging bets".

That is a rather interesting conclusion. On what do you base your claim that the mutations occur with purpose?

[RobRoy]

Call it an as yet unsupported hypothesis. ;)

[metmom]

...but I'm reasonably sure this estimate was based on known mutational rates...

Well, yeah. I would be too. But you don't know either or you wouldn't say that you were *reasonably sure*. Did you read the whole study then?

And how does asking for the method of how they determined the number of mutations indicate that I don't understand the underlying science? It was a question concerning *knowing* how they got to the estimate, not *understanding* the science.

Should nobody, then, dare to question how science was done without fear of being accused of ignorance of the science? If another *real scientist* questioned it, would he get the same *learn what you're talking about first* kind of response that creationists/IDers get? I think not.

[metmom]

Don't you have a sense of humor?

[RobRoy]

Yes ;)

[2nsdammit]

"Did you read the whole study then?"

Nope. I read the press release. I trust the scientific process enough to know that every expert in the field will question the experiment and its outcome, and they DO know the science well enough to call BS if it's wrong.

"And how does asking for the method of how they determined the number of mutations indicate that I don't understand the underlying science? It was a question concerning *knowing* how they got to the estimate, not *understanding* the science."

So do you understand the science? I don't - I have already said that I'm not a molecular biologist; are you? I have enough understanding to grasp the basic premise, I believe.

"Should nobody, then, dare to question how science was done without fear of being accused of ignorance of the science? If another *real scientist* questioned it, would he get the same *learn what you're talking about first* kind of response that creationists/IDers get? I think not."

Absolutely another scientist, would not get told to learn what he's talking about. If you are a molecular biologist, working in the study on mutations in DNA within bacteria, I will retract my contention that you question the research because you are clueless of the science.

[2nsdammit]

"It was a question concerning *knowing* how they got to the estimate, not *understanding* the science."

Actually, I can't let this rest...

My issue with your post was not that you asked the question about where the estimate came from. My issue was with your blanket statement that "there isn't much to substantiate this", without knowing the underlying science.

But then, I suspect that you knew that.

[metmom]

No, I'm not a molecular biologist. The *met* part indicates a different branch of science. Nevertheless, it's fairly easy to conclude that it's based on past experience and experiments and that it has been extrapolated. So, it would be a pretty safe be that there was math and statistics involved , too. And lot of it is most likely junk journalism in reporting the results.

People who don't accept the ToE are generally considered not *real scientists* and regularly told to get an education and come back when they know what they are talking about, regardless of their scientific background. Even if a physicist questioned the molecular biologist's experiment, he would get more deference than is given almost any non-evo on this forum. The underlying assumption is that one who rejects evo rejects all science and is ignorant of how it and science works and that is not true. Rejecting the ToE and the interpretation of the fossil record is not a blanket rejection of science as a whole.

[Conservative Texan Mom]

Thanks, I got it. The article said the study's results were reproducible. That's what got me to wonder about this. But, the study also started with a large number of bacteria, so I don't know that it was comparable in the way I was thinking.

[Conservative Texan Mom]

Interesting! Thank you.

[grey_whiskers]

That the original mutation occurs, but the daughter cells *die* of causes other than the one the mutation gives an advantage for. Say predators, macrophages, or Pine Sol.

An isolated environment would help keep that from happening.

Cheers!

[Right Wing Professor]

That the original mutation occurs, but the daughter cells *die* of causes other than the one the mutation gives an advantage for. Say predators, macrophages, or Pine Sol.

So this adds a little noise. It doesn't change the relative selective advantage.

[grey_whiskers]

Sorry, ran off to dinner.

So this adds a little noise. It doesn't change the relative selective advantage.

That's my point, that it does add noise. So while it does a great job of illustrating the processes involved, it might give an erroneous estimate of the rate at which mutations take hold and propagate.

The next step would be to apply find a separate second stressor on the population, and systematically vary that to see the mutation rate for selection involving only the second stressor.

Then perform an experiment where both things are varied simultaneously, to see how multiple selection pressures interfere one with another...

Cheers!