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Re: Natural Selection - The Whole Story ?



It would seem to me that the simplest answer to the problem of co -
evolution would go something like this: Flowers exclusively pollinated by
bats were not always pollinated exclusively by bats. Scarlet king snakes
and coral snakes are both secretive, occupying similar habitat and exposed
to similar predators. It's not surprising that their colors and patterns
are similar. Co - evolution, particularly in long standing communities
like coral reefs and rain forests could proceed by natural selection
alone.

Steve

Stephen Faust                   smfaust@edisto.cofc.edu

On Tue, 11 Aug 1998, Roy Nash wrote:

> At 21:44 07/08/98 EDT, Caleb Lewis wrote:
> 
> > My question is: How does evolution seem to know what to evolve or make 
> > one species evolve into next? 
> 
> and in reply Dinogeorge wrote:
> 
> >By natural selection.
> 
> Others wrote brief explanations of natural selection being all about
> countless random mutations of offspring, the survival of the fittest etc
> which I'm sure Caleb was already well aware of. But Caleb is right to have
> doubts. Although the process of natural selection can be demonstrated, it
> cannot be proved that it is the ONLY process by which evolution occurs.
> Proponents of natural selection have great difficulty in explaining the
> co-evolution of organisms within an eco-system. For example, how can
> flowers that are only pollenated by bats that feed exclusively on their
> nectar be explained ?  How is mimicry explained - yes we know that a fly
> that looks like a bee is less likely to be eaten therefore it is "fit" but
> how does it ever get to a "fit" state when its unbee-like parents were eaten ?
> 
> What natural selection seems to lack is feedback or more specifically the
> Gaian concept of "communication" between organisms and the eco-system they
> belong to. To Gaians evolution need not be random or gradual although there
> is still no particular direction to it. Gaians would not be surprised (see
> David Lessin's mail) that landlocked sunfish acquire a pike-like morphology
> after a few generations, that other fish change sex when necessary, that
> various species of amphibians retain partially juvenile morphology in some
> areas and develop to normal adults in others. All are cases of the
> organisms responding to cues from their eco-system - the eco-system somehow
> responsible for switching specific genes off or on. 
> 
> The eco-system also includes other organisms. A more radical view is that
> it is possible that organisms orchestrate each others evolution. This may
> be to produce a symbiosis in which both (or all participating)organisms
> benefit, a parasitic relationship, or a food-chain. 
>  
> 
>