Question For Evo's Re: Fruit Fly Mutations

I'm constantly reading the creationist argument that the fruit fly experiments never resulted in a single beneficial mutation. What is the evolutionist response to this? I know that beneficial mutations have been observed elsewhere, and I also know that beneficial mutations are relatively rare, but there has been a lot of fruit fly experiments and no beneficial mutations that I know of. Is this result to be expected?Thanks in advance.

The problem is the idea of "beneficial mutation."How do you know if something is beneficial? It is so intimately tied up with the environment in which the organism lives, how can one possibly tell if any given mutation is beneficial?That can only come from longer population studies.If you're looking for studies on beneficial mutations, you might consider going to PubMed and do a search for "beneficial mutations" and see what you get.------------------
Rrhain
WWJD? JWRTFM!

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I'm constantly reading the creationist argument that the fruit fly experiments never resulted in a single beneficial mutation.

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Maybe you should stop reading it. Quick fix.

That's a little harsh. After all we wouldn't want people to think that a creationist argument was so compelling that our only choice was to ignore it, right?As for beneficial mutations in fruit flies, like Rrhain said, "beneficial" has to be taken in context of environment. If the fruit flies are being raised in a lab, the lab environment by design is supposed to limit the degree of interaction between flies and environment. So the lab might not be the best place to test for beneficial mutations.That said, if you set up an experiment - say, expose a population of flies to weak levels of insecticide - I'm confident that, eventually, you'd have a population of flies that were resistant or even immune to the poison. I don't know if anybody has ever done that with flies but it happens all the time with antibiotics and bacteria. It would take a lot longer to get results from the flies.

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That's a little harsh. After all we wouldn't want people to think that a creationist argument was so compelling that our only choice was to ignore it, right?

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Good point... I mean the exact opposite, i.e. it's ridiculous to generalize from our experience with one species when we know full well that beneficial mutations are rare but still observed in myriad other circumstances. It's like saying I walked outside one day and it was sunny, so rain is a logical impossibility.

and why should the fruit fly experiments be your only resource in an argument like this?

In the big picture they certainly shouldn't be. But it is interesting nonetheless. There has been a lot of work done with Drosophilia over a long time. We know a lot about them. This might be a good thread to explore more of what has been learned.I've started a search to see if they have been anything that might be called "beneficial mutations" in fruit flys.I notice that the creationist sites use phrases like "but they are still fruit flys". That kind of silliness isn't interesting.Has there been a case of speciation in the lab with fruit flys? If there has been then they are not "just fruit flys" anyomre.

I seem to recall reading that there had been. Isn't fruit fly a higher taxum than species?

What we call "fruit flys" are, whenever I read about them Drosophilia which is the genus. So yes, they are higher than species. What I am interested in is the formation of a new Droophilia species from, say, D. melanogaster.

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That said, if you set up an experiment - say, expose a population of flies to weak levels of insecticide - I'm confident that, eventually, you'd have a population of flies that were resistant or even immune to the poison. I don't know if anybody has ever done that with flies but it happens all the time with antibiotics and bacteria. It would take a lot longer to get results from the flies.

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We have been doing that kind of thing with all sorts of creepy crawlers ever since we started using pesticides of any kind.Gypsy moth, anyone?We spray like crazy for gypsey moths, only to have then come back in greater numbers than ever, and resistant to the pesticide we used before.

NosyNed writes:

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What we call "fruit flys" are, whenever I read about them Drosophilia which is the genus. So yes, they are higher than species. What I am interested in is the formation of a new Droophilia species from, say, D. melanogaster.

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Well, if you take a look at Section 5.3 of Observed Instances of Speciation, they give some documentation of speciation in Drosophila.It might serve as a starting point.------------------
Rrhain
WWJD? JWRTFM!

I agree that they shouldn't be the only resource but that doesn't stop some creationists citing the fruit fly example as evidence that beneficial mutations are too rare to fuel evolutionary development in the long run. I was just wondering if it was particularly strange that there were none observed in the fruit flies considering how many experiments have been performed on them.

Well..... what do you mean by "beneficial". The problem here is that is a term carrying a value, when mutations do not.Some changes will TURN OUT to be beneficial. Perhaps a random mutation changes the colour pattern of a cow from plain brown to party-coloured black and white. Perhaps, at certain times and places, this is better camo and breeds on. Or not. Who can say? "Beneficial" is nto an objective property that a mutation possesses.So yo answer your question, No, it would not be surprising if no "beneficial mutations" were observed (although this is a position I do not support) becuase of fuzziness over what "beneficial" means or is, now or in the long term.

It really depends how many experiments have been done specifically to try and produce beneficial mutations in fruit fly populations. I don't how often this has been attempted.Insecticide resistance seems like a good area to look at, there are certainly a lot of studies on this in natural Drosophila populations.
How about this example on insect repellantReeder NL, Ganz PJ, Carlson JR, Saunders CW.
Isolation of a deet-insensitive mutant of Drosophila melanogaster (Diptera: Drosophilidae).
J Econ Entomol. 2001 Dec;94(6):1584-8.Oooh heres an insecticide oneAdcock GJ, Batterham P, Kelly LE, McKenzie JA.
Cyromazine resistance in Drosophila melanogaster (Diptera: Drosophilidae) generated by ethyl methanesulfonate mutagenesis.
J Econ Entomol. 1993 Aug;86(4):1001-8.

Woudln't this be natural selection, instead of evolution ? Like putting dogs in the snow and when the hairy dogs survive, you say they must have evolved, more likely the ones best suited for the environment survived ?