Question for evolutionists

[Rduke55]

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Whoa! You can't say genotype is more important than phenotype. They're both equally important. Selection acts on the phenotype, the genotype is what is passed on.

And the phenotype dosn't change, the frequency of phenotypes change.

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Phenotype is merely a medium through which a genotype may establish its fitness within particular environmental conditions.

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Think about this statement a little more.

[Rduke55]

Also, what about changes in the genotype that do not have an effect on phenotype? Or are neutral in regards to selection?

I'm not saying phenotype is more important than genotype. I'm saying you cannot say one is more important than another.

[benkahuna]

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Also, what about changes in the genotype that do not have an effect on phenotype? Or are neutral in regards to selection?

I'm not saying phenotype is more important than genotype. I'm saying you cannot say one is more important than another.

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Because the phenotypes of an organism are dynamic through its lifetime, I think you first need to at least call them phenotypes. I don't think you're properly considering regulatory genes or recessive traits. A heterozygous condition of a particular allele may not result in major problems for an organism and may thus be exempt from the influences of a selective pressure. Still, these traits may change the likelihood of producing fertile offspring as two heterozygous parents may have 1/4 of their kids with the homozygous recessive condition and those kids die before sexual maturity.

Certain genes do not have 100 percent penetrance and as long as they're latent, everything is fine. If they become active, it can get messy. Such genes may seriously impair the production of fertile offspring, even if they have no impact on the progenitor.

I don't think a given phenotype is unimportant, but genotype is clearly more important. Genotypes represent everything that is possible (along with mostly the mother's double membrane bound organelles and the initially correct conditions in humans) whereas phenotype is simply the expressed genes and resultant morphology/physiology at the time.

If a genotype has the best selection of possible phenotypes, but only one of which is expressed and has the same phenotype as another organism with a different genotype and a less favorable mix of possible phenotypes the superior genotype breaks the tie in terms of fitness and thus genotype is more important.

[Rduke55]

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Also, what about changes in the genotype that do not have an effect on phenotype? Or are neutral in regards to selection?

I'm not saying phenotype is more important than genotype. I'm saying you cannot say one is more important than another.

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Because the phenotypes of an organism are dynamic through its lifetime, I think you first need to at least call them phenotypes. I don't think you're properly considering regulatory genes or recessive traits. A heterozygous condition of a particular allele may not result in major problems for an organism and may thus be exempt from the influences of a selective pressure. Still, these traits may change the likelihood of producing fertile offspring as two heterozygous parents may have 1/4 of their kids with the homozygous recessive condition and those kids die before sexual maturity.

Certain genes do not have 100 percent penetrance and as long as they're latent, everything is fine. If they become active, it can get messy. Such genes may seriously impair the production of fertile offspring, even if they have no impact on the progenitor.

I don't think a given phenotype is unimportant, but genotype is clearly more important. Genotypes represent everything that is possible (along with mostly the mother's double membrane bound organelles and the initially correct conditions in humans) whereas phenotype is simply the expressed genes and resultant morphology/physiology at the time.

If a genotype has the best selection of possible phenotypes, but only one of which is expressed and has the same phenotype as another organism with a different genotype and a less favorable mix of possible phenotypes the superior genotype breaks the tie in terms of fitness and thus genotype is more important.

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I don't think you're thinking about this on the right level.
They absolutely cannot be separated in importance to evolution. I just don't know why you keep arguing one over the other. Especially using words like "clearly" more important. Whether or not phenotypes change is not the issue.
They are both neccessary and essential for selection.
It seems like you have a grasp of how genes work but I think you're not thinking about the big picture here.

Darwin postulated 3 conditions for natural selection. 1) Variation of traits in a species, 2) Heredity of those traits, 3) Differential reproductive success based on those variations.
The first is genotype expressed as phenotype. The second is mainly genotype. The third one is mainly phenotype.
Take away any of those and the whole process does not exist.
When something is necessary and essential for a process you can't say something else that is also neccessary and essential is more important.

I just don't understand where you're coming from on this.