Re: Part 1 (of 3): What are major aspects of evolutionary theory?

> I never cared for the "fitness landscape" metaphor because it assumes
> that fitness is a continuous function of whatever is on the axes of
> variation. These are not continuous parameters and subtle changes in
> regulatory genes can produce rather abrupt and discontinuous changes
> in phenotype, hence in fitness.

I suppose the rationale is that most non-fatal mutations are really
tiny steps, and a continuous landscape is a reasonable mathematical
model for a descrete but very finely-divided staircase. Really huge
regulatory changes usually screw up the overall interlocked system so
badly as to be virtually always fatal. Or such changes make one
individual totally incompatible with all other members of what was his
species, so even if he can survive, he can't produce offspring. So most
of the time giant steps can be ignored as a course of evolution. But
all it takes is one such giant mutation to succeed every few million
years, something making an allelle very much more successful than the
ancestral allelle, yet not mating-incompatible, and suddenly there's a
big evolutionary jump. So maybe the correct metaphor is a fitness
landscape with the ability of individuals to shout "Geronimo" and jump
into a strong breeze with a hang-glider and take their chances where
they might land on a new island far from home.

> Still, the fact is that evolution is always about populations and
> never about individuals. Selection pressure changes the allele
> frequency in a population.

You're seeing only half the picture of evolution, the half whereby
already-exiting variation is tested and only the best is retained.
You're overlooking the other half of evolution, whereby one individual
suffers a mutation whch changes the fitness of that individual and of
any descendents that individual might begat, thereby adding new
variation to the population. That individual's mutation, and the
mutations within other individual, are essential for evolution to
produce new characters rather than merely narrow down the whole world's
life to a single genotype.

The anti-evolutionists, who claim evolution can only purify the race,
never produce a new race, make the same omission you made there. You
are playing into their hands, giving them quotes to mine.
..

.

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