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Darwin's theory
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My answers in blue below.yes thats the link.take a good read of it J C.tell us what you think:D
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The multiplication rule does not apply to biological evolution. A common error in the non-scientific literature and poorly written papers is to assume that probabilities multiply for computing components of living things such as proteins. Not an error - and the multiplication rule applies to sequential phenomena in Biology, just like all other sequential phenomena.
A typical argument notes that proteins are about 300 amino acids long and that there are 20 different kinds of amino acids. If such a string were to be generated using independent selection of the amino acids, then the probability of generating any particular string is 20-300, a very small number indeed.
Correct.
While this may be true for random strings, it does not directly apply to proteins found in living organisms. It does, unless there is intelligent intervention.
Why? Because individual mutations accumulate one-at-a-time and there is amplification (replication) between steps. That is, if one starts with a given amino acid string, the mutations in the genome (from which the string is derived) are sequential. A mutation occurs, perhaps changing the amino acid string. If the change is bad, which is true for the majority of changes, the organism dies and its genes are gone. Most cases result in debility rather than death ... thus resulting in a build-up of deleterious mutations within the population.
(In diploids, recessive defects will be removed more slowly since they are only exposed when an organism becomes homozygous for the mutation.) This causes further build-up of deleterious and lethal mutations within the genome, 'hiding' in a hetrozygous state.
If a rare lucky change occurs that has some advantage (or at best is neutral or only slightly deleterious) then the organism may survive to produce offspring. head of Tyrannosaurus Rex The possibility of appearance and acceptance (by natural selection processes) of mutations in the offspring therefore depends strongly on whether the previous generation survived and on the number of progeny. The organism may or may not survive (due to other items in it's 'mutation load') ... but, in any event, while a single change to a critical functional sequence can result in a lethal or semi-lethal condition ... a single change in the direction of an advantageous trait will have no phenotype effect until all of the sequence is present and integrated with all other systems required to generate the effect.
... so while NS can 'weed-out' deleterious traits ... it is powerless to generate useful traits de novo, because it cannot identify intermediate sequences 'moving towards' a useful functional sequence ... because this isn't expressed (and therefore selectable) until the entire functional sequence is present.
Genetic algorithm experiments, such as the Ev evolution program demonstrate clearly that the probability of generating what would be an extremely rare genetic string if the steps were independent, can be high. So the evolution of a 300 amino acid protein is reasonably easy to attain.They demonstrate no such thing.
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