jamenegay{at}ra.rockwell.com (Jim Menegay) wrote in
news:brm677$4dn$1{at}darwin.ediacara.org: 

> "Malcolm"  wrote in message
> news:... 
>> "Jim Menegay"  wrote in message
>
>> Using evolution, it is difficult to push back our understanding 
>> beyond this ancestor, but it cannot have appeared at a stroke.
 
> Certainly it could not have appeared at a stroke!  Therefore,
> evolution must have been in operation long before this complex common
> ancestor. Something much simpler "appeared at a stroke" and then
> evolved to the LCA.  An evolving "RNA world" is a cliche today, and I
> suspect that there may have been other evolving entities before there
> were RNA sequences.

Daniel Dennett, who is an "evolutionary philosopher" if there is such a 
thing, would agree with you ( as would others who think evolution only 
requires replicators).

 
> What I don't understand is your assertion that it is difficult to push
> back our understanding beyond the LCA, *using evolution*.  It is
> certainly true that it is impossible to push back our understanding
> using phylogenic inference.  But an understanding of the processes of
> evolution must certainly be useful in pushing our understanding back -
> after all, it is evolution that provides the dynamics leading from the
> "stroke" to the LCA. 

Given your interest in studying the basics of biochemistry as they apply 
to evolution, I suspect you might also be interested in some of the work 
that attempts to explain the appearance of complexity as a general 
phenomenon of non-equilibrium systems. This work attempts  to bridge the 
divide between chemistry and biology. Stuart Kauffman is a leading expert 
in the field, but the only book I have by him - "Investigations" - I have 
found rather impenetrable. Apparently his "Coming of Age in the 
Universe" is more readable, but I have heard that there are better 
introductions to this subject - unfortunately I can't remember any names.

Yours,

Bill Morse
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