> Many YEC calculate probabilities of arranging the gene code based on only one possible viable sequence. We have learned that for every gene, a small variety of sequences are just fine. Now there is not one possible goal, but something like 14 raised to the power 30,000 which works out to approximately 10^(34,384). (Did I do that right ?) These varieties are only those alive now, what about relatively viable options that existed in the past !<
Although it obviously depends on the assumptions of the model, you can reconstruct past DNA sequences based on a consensus of modern ones. More importantly for such calculations, many genes occur in several different organisms performing the exact same functions, and much of the genome in most organisms varies freely (non-coding, non-signaling regions). Thus, the number of possible functional DNA combinations is enormous, though of course so are the number of non-functional ones.
The calculations of probability also usually overlook two highly non-random aspects of evolution. First, natural selection can strongly select against detrimental mutations, so many mutations have little or no chance of persisting in the genome. Secondly, mutations in a protein-coding gene will probably still produce a protein-coding gene unless the mutation silences expression. Many basic structural features can function in several different proteins; conversely, very different proteins may perform the exact same function.
Dr. David Campbell
"Old Seashells"
46860 Hilton Dr #1113
Lexington Park MD 20653 USA
bivalve@mail.davidson.alumlink.com
"That is Uncle Joe, taken in the masonic regalia of a Grand Exalted Periwinkle of the Mystic Order of Whelks"-P.G. Wodehouse, Romance at Droigate Spa
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