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Re: Evolutionary Theory

>My high-school biology teacher (who hates creation) taught us that 99.9999...%
>of all mutations are destructive and don't get passed on in future
>generations. So I fail to see how random mutations could result in something
>better. Even if there was a beneficial mutation, would it get passed on to its
>offspring in future generations?

Good question.  The mutation percentage is not entirely accurate.  If the 
mutation occurs in a Recessive Gene, then the effects could remain unknown for 
generations.  It's when the mutation occurs in a Dominant Gene that things 
begin to get interesting.

Also, mutations have a varying effect on the organism.  Some do nothing more 
than cause wierd color patterns.  Others can be fatal.  It really depends on 
where the "genetic error" occurs (this cannot be predicted, BTW).  It turns out 
that most mutations don't show up at all, especialy when it occurs in a part of 
the genetic code that isn't active (like the "tail gene" in ourselves).

Small mutations occur in nature all the time.  In watching a herd of deer, 
biologists have observed how the coats of these animals change as long term 
weather changes occur.  If the climate is warmer than average for a few years, 
the deer will have lighter coats.  If the climate is colder than average, the 
coats become heavier.  These changes occur as animals continually adapt and 
re-adapt to their environment.

Ultimately, all evolution and all adaptation comes from the genetic level.  It 
is because of those little "missteps" that a population of animals has the 
variation needed to facilitate evolution.


Rob Meyerson

Early bird gets the worm, but the second mouse gets the cheese.