Re: [asa] ORIGINS: pseudogenes are overwhelming evidence for evolution...?

The "junk DNA isn't really junk" argument fails to answer the actual
correspondance between observed non-functional patterns in DNA and
evolutionary expectations. Some, though not all, of the non-gene
coding DNA does have important functions. However, many details of
both coding and non-coding DNA do not have function. The pattern of
distribution of such features corresponds to that expected from an
evolutionary perspective. Because evolution specifically predicts the
observed patterns, whereas post hoc modifications of separate creation
models could generate any pattern, including the observed ones, this
is generally taken as evidence in favor of evolutionary models. For
example, having a cox1 gene in the mitochondrial DNA is important to
essentially all eukaryotes. However, the exact protein sequence can
vary, and there is wide freedom to vary in parts of the DNA sequence
(third bases in most codons, etc.). Also, it doesn't seem to matter
what genes it is next to. Gene sequence within the mitochondrial DNA
is very stable in some groups (e.g., vertebrates) and highly variable
in others (e.g., mollusks); where there is variation the pattern
matches evolutionary expectations. The DNA sequences for cox 1 show
patterns of similarity that match evolutionary expectations, although
distantly related species may be essentially randomized relative to
each other and there are occasional peculiarities like distinct male
and female mitochondrial lineages (which occasionally recombine in
some taxa) in many clams. There are even additions or deletions of
amino acids to the protein, which show patterns in accord with
evolutionary expectations.

-- 
Dr. David Campbell
425 Scientific Collections
University of Alabama
"I think of my happy condition, surrounded by acres of clams"
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