So where has this got us? (I am a founder member of the William of Occam  
Appreciation Society)
 
Genes (or sections of DNA coding) recombine during sexual reproduction and  
the children won't be exactly like the parents.
 
There's a lot of spare capacity already within the genome that can be  
switched on or off by stimuli (or at random?) during the reproductive  phases.
 
There's a constant trickle of mutation, some of which might be useful, most  
of which isn't, and some of which may be lethal.
 
A change of diet or other chemical stimulus at the appropriate time may  tend 
to accelerate these processes.
 
Have I got it about right?
 
Chris
 
 

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