mutation and evolution

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The problem I see with that line of reasoning is that if you take into account that a new species can only arise from
a previous species, according to evolutionary theory, then you can only take into account the mutations that occur
within the parent species. That would lower the mutation rate significantly.

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Evolution isn't just about mutation, or natural selection, or ...Evolution occurs as a system-level effect of the interaction
of a number of component forces. In particular it requires some
form of separation followed by isolation of a (sub-)population.As pointed out, it is suggested that mutation rates are much
higher than previously thought. It is also the case that (in
sexually reproducing organism anyway) that it is not one mutation
in the parent ... each (male) parent produces millions of gametes
each with the potential for copy errors.

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If species A has a mutation, however it has no way to pass the mutation to species B that survives in the
immediate area, the mutation would have no significance in population B.
Therefore the populations that are
affected and have the ability for mutation decrease significantly.

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Suppose species A has offspring Aa and Ab which differ slightly
in their genome. This new population splits into two populations
(maybe separated by a flash flood or avalanche or somesuch) A1 and A2.The separation leads each population into somewhat different
habitats. A1 is in a habitat which favours Aa individuals, while
A2 is located where Ab is the thing to be.The further mutations that occur in A1 and A2 are selected based
upon different environmental pressures, and the A1, A2 populations
could be further split in the future.Iterate around this for a few million years and I think you'll
see a marked difference in the extant populations.

Environmental changes cause a change in trait frequencies
over time ... so if the environmental pressures change
the dominate traits will change ... don't see the problem
there. If the environmental pressures don't go away, or
some of the population are isolated so that the two sub-populations
are subjected to different environmental pressures it's surely
reasonable to surmise that they would diverge. We know that such
divergence is possible (otherwise there would be fewer breeds
of dogs, cattle, cats, etc.).It's been brought up before (not sure where, sorry), but not
discussed in full (I think) ... but what about species which
can inter-breed, but produce infertile offspring?Doesn't that suggest that the species (horses&donkeys, lions&tigers,
various zebras) are diverging to a point where, should the
trend continue, they would be unable to interbreed?Is that still micro-evolution?Or is it the first step on the rung to more profound diversity?

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However if the environmental pressure were removed would the populations not tend to rebound toward their predivergent state?
Which would tend to eradicate the mutation from the population or store it in a dormant state within the population.

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Yes. The environment has changed (albeit back) so the result
would be for the trait frequencies to re-align. Unless of course
the environmental change lasted for a number of generations, during
which time some or all of the original traits were lost from the
genome ... then there is no going back.Accepting that trait frequencies fluctuate with changing environmental
pressures is something we appear to agree on though.

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If this is the case is it not possible that genetic information has always had messages in dormant states waiting to be turned on when
environmental conditions were right and off when they were not?

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Unlikely when you view the effects of selective breeding.
Traits are picked by the breeder and bred for, resulting in
a huge diversity in, say, dogs. If left to their own devices
(as in Portugal for example, where dog packs roam the streets
reasonably freely and have done so for some time), there is still
wide diversity ... even after much inter-breeding.This suggests that traits are not 'switched off' or 'made dormant'
but are irrevocably changed (although there is some emerging evidence
for re-evolution in insects I believe).

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Yes, selective breeding has led to a vast diversity of
domesticated animals. If left to nature would they not reach a state of equilibrium in their genetic material?

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See above for why I find this unlikely, feral cats in the UK are
another example that springs to mind. They still show the
domestic breed varieties (in various mixtures), but have in some
areas been left to 'nature' for many generations.Selective breeding indicates that changes can be 'selected'
into the genome in a manner that does not allow for an easy
route back to the start point.Of course no new species have been created via selective breeding
(that I am aware of) so that still remains another issue.The implicaiton of mules and ligers, though, is divegence to
the point where biologists would classify the critters as
separate species ... but that's just my opinion.

I'd certainly agree that a continually changing
environment would prevent any 're-alignment' or reversion.By species I tend to mean 'incapable of producing young
on fertility grounds.

Will this get rid of the replies await 'Yes' ....?