[Osx-nutters] The separation of church and state.

[David Cake]

At 10:08 PM +0000 7/12/07, Stefano Mori wrote:
>I'm not sure I understand... natural selection explains the "leaps" ?

	The base theory of Natural Selection as put forward by Darwin 
doesn't so much. A modern, more complex theory that incorporates more 
details of how genetics works, and has a more sophisticated 
understanding of how genetic algorithms work, allows for "leaps" 
under particular conditions and parameters.

>I get that being adapted to the environment determines what eventually 
>survives out of what's already appeared, but what's the current 
>explanation/understanding for how new things appear in the first 
>place, particularly where those new things are large complicated
>structures like eyes or wings?

	For the most part, they don't appear all at once - gliding 
precedes true flying always, for example, and gliding mechanisms can 
be as simple as excess skin flaps. Primitive eyes don't have 
focussing lenses or independent movement or multiple types of 
perceptual cell. Complex structures evolve via a long series of 
simpler changes (though sometimes with those individual changes 
evolving in an interrelated simultaneous way).
	There is a specific argument about ID that hinges on this 
exact point - the ID people contend that certain mechanisms are 
complex, and if you take a away a single part they would stop 
working, so could not have evolved part by part as natural selection 
claims. So far, none of their claimed examples have turned out to 
hold up - in every case of a claimed irreducible complex mechanism, 
partial precursors have been found.
	more, of course, in Wikipedia
http://en.wikipedia.org/wiki/Irreducible_complexity
	(it gives a nice clear description of how eyes are believed 
to have evolved)
	And Stefano, you are sounding very sympathetic to this 
argument, but it holds up very poorly to close examination, and is 
definitely in conflict with the scientific orthodoxy.
	Cheers
		David