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RE: Radiation Hormesis -- or not



That is my point.  ". . . a mutational effect, which 

changes random genes, would produce random phenotypes.

. ." While they are not uniformly superior neither are

they uniformly inferior.  



I am not a expert in plant genetics, so may be the

irradiation of seeds is a hormetic effect.  I raised

the question since it is frequently cited, and I have

not seen any detailed study of genetic changes, which

to me are not hormetic.  I think someone else said

that chemicals can also cause drastic changes in plant

responses.  This is all well and good, but what is the

implications to humans?



--- "Neil, David M" <neildm@id.doe.gov> wrote:

> Why would a genetic mutation favor a negative

> effect?  Because there are lots more ways to "do it

> wrong" than there are to "do it different but

> right".  Change as little as one peptide in insulin,

> for example, and you don't survive to breed without

> medical support.

> 

> To use your example, proto-primates which could grip

> better (within natural variation) could climb

> better, and therefore  could escape danger easier

> and survive to breed, and also had easier access to

> food (either pick-a-fruit or grab-a-bug) and

> therefore bred more frequently, more successfully

> and longer.  

> 

> As stated, the uniformity of the effect indicates

> the nature of the effect: a mutational effect, which

> changes random genes, would produce random

> phenotypes, not uniformly superior phenotypes.

> 

> Dave Neil  

> B.A. Zoology, University of South Florida

> 

> 

> -----Original Message-----

> From: John Jacobus [mailto:crispy_bird@yahoo.com]

> Sent: Monday, January 26, 2004 2:17 PM

> To: Neil, David M; Carl Speer;

> radsafe@list.vanderbilt.edu

> Subject: RE: Radiation Hormesis -- or not

> 

> 

> Why would a genetic mutation favor a negative

> effect? 

> After all, evolution shows that genetic effects are

> positive since they allow the organism to adapt. 

> Primates did not get opposed thumbs by willing it to

> happen.  It was genetics.

> 

> Again, my statement was that it should have been

> checked to see if it was a genetic mutation by

> following the growth pattern of the off-spring. 

> 

> <SNIP>





=====

+++++++++++++++++++

"I have sworn upon the altar of God, eternal hostility against every form of tyranny over the mind of man."

Thomas Jefferson



-- John

John Jacobus, MS

Certified Health Physicist

e-mail:  crispy_bird@yahoo.com



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