- Jul 21, 2005Paul: Here is an article about the inability of
critics to overcome objections based on irreducible
complexity without resorting to just so stories based
on faith that suitable mechanisms will be found.
From the article:
'Origin of genomic regulatory systems'
"The nature and degree of gene expression is commonly
governed by a tightly intertwined set of regulatory
elements found on the DNA molecule. How is such a
concert of regulatory elements supposed to have
evolved as a unit? The scenario invoked has a distinct
flavour of storytelling:
Advantageous substitutions in regulatory elements
caused by genetic factors are most interesting. They
must be responsible for morphological evolution as
discussed before. When a new chain of gene expression
patterns for transcription factors and signal
transduction elements is appearing, many advantageous
mutations are thought to occur simultaneously at the
loci participating in the chain. This process is
called recruitment or cooption by developmental
How such a chain originates is a very difficult
problem, i.e., a module of interacting gene loci would
have to be constantly tested by natural selection
under various genetic and external factors. On very
rare occasions, while wandering via mutation and drift
under available transcription factors, a module might
find its place in a larger gene regulation network.
Then positive selection may work on the regulatory
elements of the module loci3 [emphasis added]."
Paul: Storytelling indeed. Backing up the stories
with solid evidence is a good deal more difficult.
Cliff has raised the point that in his view evolution
was not characterized by gradualism or at least not so
at all times. Even if you assume this to be true
where is the evidence that a step by step process
(gradual or sudden) lead to regulatory systems that
are ubiquitous in organisms?