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0 pointsdschiptsov10y ago0 comments

Nope. Mutations in a single organism are almost irrelevant. They must propagate via offsprings (be selected in meiosis) and eventually spread throughout population, otherwise they will be lost. This is a protective mechanism without which there will be no stable traits and no complex organic life at all.

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_0w8t10y ago· 1 in thread

I fail to see how this disproves that phenotype can alter genotype through the speed of mutations. The point is that after environmental change there is a limited timeframe when a population can develop a trait essential for survival in the new situation. If the rate of mutations is low, the whole population will simply die.

However, if by phenotype changes the mutation rate can be increased, then the population can adopt. In that case the new genotype trait essential for survival will be available only in offspring coming from phenotype that allowed faster rate of mutations. This is a data flow from phenotype to DNA.

dschiptsovOP10y ago

Mutations are random. Increasing mutation rates for such a complex organisms as humans is the same as increasing the probably of cancers and negative mutations. Only bacteria could afford this.

Species whose mutation rate fluctuates according to its diet wouldn't last too long.

Oversimplified models doesn't represent mostly-stohastic reality, especially in genetics.

And, still, the one way flow of information is the fundamental principle which makes complex organs such as heart, brain or liver possible.

Everything which contradicts a fundamental principle is merely a mental abstraction. Or a story.

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