Re: Minimization principal for evolution



"Perplexed in Peoria" jimmenegay@xxxxxxxxxxxxx wrote:

References: <dsp9a7$2r06$1@xxxxxxxxxxxxxxxxxxx>
...one thing still puzzles me about this picture - the fact that
fitness is not measurably heritable. And one frequently sees the
suggestion that the reason fitness heritability is so unmeasurably
small is that organisms are already pretty well adapted to their
current environments. Maybe not exactly at the summit or 'peak' of
their fitness landscape, but at least in the almost-flat region near
the top of the 'hill'.

JE:-
Nature is always right. The reason as to why "fitness is not measurably
heritable" is because the definitions of fitness and heritability that are
being employed are not empirically correct.

This is doubly puzzling since a heritability coefficient for fitness
should also include positive components for 'maintenance of type'
and for any adjustments driven by recent environment changes. But
these are usually too small to be measured as well.

JE:-
I think that Dr Moran enjoys non adaptation type self fulfilling
(tautological) prophecies.


Of course, you can measure heritability of fitness only to the extent
that there is genomically-caused variation in fitness. So one way
to reconcile Larry's claim (that organisms are far from peak adaptation)
with the measurements is to claim that the mutations that would make
organisms even more fit in the current environment just haven't
happened yet.

JE:-
Yes, where this is almost always the case which unfortunately protects Dr
Moran's position from being tested.


But, if we wait long enough, eventually they will happen,...

JE:-
Yes, eventually you too must become a billionaire if you can just "wait long
enough". Meanwhile, for Dr Moran, it is just business as usual :-)




snip<

Regards,

John Edser
Independent Researcher



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Relevant Pages

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  • Re: Heritability of fitness
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