The Nature of Mutations II

No it isn't evolution in the sense of 'development' it is evolution by natural selection.I see no need to put descended in quotes when talking about the descent of all cells from the zygote, they aren't called daughter cells for nothing.It certainly is relevant to evolutionary theory. Evolutionary processes can occur within any population. It may not be relevant to geographical timescale evolutionary history of organismal life on the planet, although I would argue that it is relevant at least indirectly, but it is certainly relevant to the theory of evolution.

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rolling die also does not work...you know a side must come up...you don't know that a mutation has to occur.

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How about flipping a coin then? Heads or tails is the desired
outcome, but sometimes it lands on an edge and just stands thereAll I was trying to say, and the above seems to support my
opinion, is that 'unpredictability' is a feature or mutation
rather than an additional consideration.If you bomabard a critter with known mutagens, and even then
cannot be 100% certain to get a mutation then uncertainty is
part of the mix.

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No it isn't evolution in the sense of 'development' it is evolution by natural selection.

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OK. It's like I said I cannot access the article, so I need more
information to impart my opinion.What are the environmental pressures that are leading cancer cells
to evolve?

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I see no need to put descended in quotes when talking about the descent of all cells from the zygote, they aren't called daughter cells for nothing.

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I had always assumed that the term 'daughter cell' was somewhat
allegorical.If one views mutation as a low-level event (which I suppose
one must) then a mutation is a copy-error introduced at the
time of cell division. And that's it.This discussion is heading into the nature of 'heredidity' which
may well be more interesting (from my PoV anyhow).

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It certainly is relevant to evolutionary theory. Evolutionary processes can occur within any population. It may not be relevant to geographical timescale evolutionary history of organismal life on the planet, although I would argue that it is relevant at least indirectly, but it is certainly relevant to the theory of evolution.

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Now we need to define 'population' -- I can see why it gets
tricky!!!Is a cell within a tissue a member of a population?
I guess so.Wouldn't that suggest that cells on the boundary of any particular
tissue would differ from those within it (since the environment
would be different one would assume that any somatic mutation
would have differing fitness benefits depending on location within
a tissue).That leads to a curious connundrum -- cancer cells are fitter than
other tissue-cells (due to having a reproductive advantage), but their
reproduction ultimately destroys the environment in which they
live -- sounds very like a certain hairless ape I read about
somewhere

I guess that article must be one I have institutional acces to.Here are a couple of free access ones which are along similar lines. Jackson AL, Loeb LA.
The mutation rate and cancer.
Genetics. 1998 Apr;148(4):1483-90Cairns J.
Mutation and cancer: the antecedents to our studies of adaptive mutation.
Genetics. 1998 Apr;148(4):1433-40.Both of these are review papers that discuss selection and apaptation in cancers.

I think I get the basic idea (probably-sort-of ).They still make a specific distintion between somatic
and germ-line mutations.There is no indication of a concept of 'heredity' involved
in tumour growth either. It's seems to be viewed as that --
growth of a tissue-type, with a focus on how that particluar
tissue type could come into being. Adaptive mutations seems
like an interesting area of investigation.

How can there be no heredity and yet be clonal selection? Obviously the daughter cells of a cell with a specific genotype will inherit that genotype, unless they undergo further mutation. In what way is heredity not involved. Surely the concept of heredity is as inherent for any proliferating cell population as for any reproducing population of animals?The only distinction between somatic and germ line mutations is where they occur.

OK, you've convinced me.

Sadly our sudden accord seems to have killed this thread stone dead, anyone else got any thoughts on mutation?

I could start disagreeing again, if you like