In a message dated 9/24/2005 8:03:36 AM Eastern Daylight Time, 
[EMAIL PROTECTED] writes:

> How can blind cave fish could result purely from random mutations (among 
> several sub species no less)? I believe that several billion tetras must have 
> been sucked into Mexican caves in order for "random mutations" to account for 
> this. 
> 

It does not happen with a single random mutation but in fish living in caves 
with no "need" for eyes genetic drift will ocur and without the selection 
pressure that favors those with vision there will be a loss of vision. There 
may 
also have been some advantage to the sightless (or poorly sighted individuals) 
that gave some advantages over the sighted fish. 
In general ,your incredulity about the power of mutattion to account for 
adaptation is an old one that has been addressed many times and in many 
studies. 
Mutation does not drive selection. Organisms do not sit around waiting for some 
hopeful monster to arrise. Rather natural variation in the gene pool of a 
species including mutations are acted upon by selection.    
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