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