Is there any proof of beneficial mutations?

Maybe he took my hint and went to find out about this new exciting "Google" thingamajig that everyone's talking about nowadays.

Hrm, well, I was either thinking of a different paper (which of course I can't find, now) or I was thinking of a different claim.To some extent the distinctions between single-celled (but consensus-building) organisms, colonial organisms, and multicellular organisms are somewhat arbitrary. But here's a paper that appears to be more on point:

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Cell types are fundamental units of multicellular life but their evolution is obscure. How did the first cell types emerge and become distinct in animal evolution? What were the sets of cell types that existed at important evolutionary nodes that represent eumetazoan or bilaterian ancestors? How did these ancient cell types diversify further during the evolution of organ systems in the descending evolutionary lines? The recent advent of cell type molecular fingerprinting has yielded initial insights into the evolutionary interrelationships of cell types between remote animal phyla and has allowed us to define some first principles of cell type diversification in animal evolution.

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Nature Reviews Genetics 9, 868-882 (November 2008) | doi:10.1038/nrg2416

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The evolution of cell types in animals: emerging principles from molecular studies
Detlev Arendt

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The evolution of cell types in animals: emerging principles from molecular studies | Nature Reviews Genetics

This may be a different subject.The environment selects for survival after a mutation has occurred. Is there evidence that the environment influences mutation before the mutation occurs?eg; does the presence of nylon cause the bacteria to develop a taste for nylon?

It probably is. But seeing as the OPer isn't coming back and the OP has been answered rather succinctly thrice thrice over...There's certainly the standard mutagens; chemical reagents that interfere, strong radiation, etc. that will result in more mutations occuring.But as for nylon resulting in mutations that make it easier to metabolise nylon*, I don't think so. It's more the case that where you don't have nylon, the proteins that metabolise it are useless and get selected against; where they are useful, they get selected for. Just like normal -- no "preselection" or "concious adaptation" involved as several creationists prefer to claim.*IIRC it's not actually nylon, but the monomers in the wastewater that get thrown out.

I dont mean to infer any consciousness.So the environment never causes a particular mutation to occur? Or, any mutation may occur in any environment?

No, there is no evidence of a direct environment-to-genome mechanism.What comes close, though, is the fact that when under environmental stress a colony of bacteria will often quicken their individual mutation rates in hopes of hitting on some useful mutation before the colony dies out completely (Adaptive Mutation). But this is normal random mutation (though sped up) without any targeted goal.I do not know enough about Flavobacterium to say with certainty, but Adaptive Mutation may have been the vector of the nylon munchers.

I dont know who started this tread, but I'm quite sure both IDists and Evoists are in agreement as to whether or not a mutation can bring about advantageous function in it's environment. Though most all examples of these are due to genetic loss, there are plenty of examples of these, as well as some debatable ones for genetic gain.

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So the environment never causes a particular mutation to occur? Or, any mutation may occur in any environment?

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Not true, since wingless beetles on islands are a perfect example of the environment effecting mutation.

No.While you yourself remain so utterly hopelessly confused about the theory of evolution you should stop trying to teach it to others.

I believe I have read somewhere on these boards that when some metabolic genes in bacteria are made to work overtime as a result of their environment, they become more likely to mutate than is otherwise the case. Hopefully whoever posted the link the first time around will post it again.However, this does not predispose towards a particular mutation, it just increases the likelihood of a mutation in a particular place.And of course any such mutation could happen in an environment which was not particularly stressing the gene.So yes, you're right. Even in this special case, the environment cannot be said to cause a particular mutation, nor will the mutations that arise be impossible in other environments.The reason is that the copying mechanisms in the cell can't think --- they can't say to themselves ... hmm, the environment is like this ... so my offspring would be better off if this protein was like that ... which I could achieve by miscopying a T as an A just here ...(We might imagine a mechanism that toggled between two versions of a gene in response to environmental stimuli, that would be fascinating. But there can be nothing in the cell with the intelligence to perform general tasks of genetic engineering.)

I dont mean to imply consciousness but does this not suggest it? Why should mutations increase when the organism is under stress?

No, no more than the other things bacteria do. Because that trait is itself beneficial and would be selected for. When things aren't going well, it's probably a good idea to change your approach.(And see my previous post --- if something in particular is not going well, it's probably a good idea to change that.)

Look at that. You answered me before I asked the question.

Environment does indeed cause mutations (mutagens, cosmic rays, etc.) but the resultant mutations are random, not specifically targeted toward a result.Use caution here. Any place in the genome is a mutation candidate, but, some areas are more robustly repaired than others. Also, outside the bacteria species, in the true multi-cellular creatures like trees, turtles and people, it is only a mutation in a germ-line cell that may get passed on to the offspring. A mutation in a somatic cell will have little to no effect on the organism (unless it's cancerous).Regardless, all are random and have no predetermined value.

Here, this might help.A bacterium can, of course, "feel" its environment. Too hot/cold, dry/wet, food/no food. Different genes are switched on or off depending upon the "stress" felt. All this was "learned" by the bacteria through random mutation/natural selection over many billions of years.