Re: Who Starts Evolution?

[Dann Pigdon <dannj@alphalink.com.au>]

From:  <george@dinosaurgeorge.com> 

> Is there anything to suggest that one sex over another would have more
> of a role in starting an evolutionary change within a species? In
> other words, would males be more likely to "start" the process of
> evolutionary change, or would females be that catalyst to begin the
> process?

Amongst humans, males tend to provide more evolutionary 'ammunition'. Once a 
woman reaches pubity she already has all of the ovae that she'll ever have. 
Once she runs out she won't make any new ones. That means that all of her 
ovae were produced while she was young. 

Men, on the other hand, can continue producing sperm cells for the rest of 
their life. As men get older, replication errors can begin to accumulate in 
the DNA of sperm cells (copies of copies of copies, etc). For instance, the 
initial mutation causing haemophilia in the British royal family seems to be 
tracable back to one particular man who fathered children late in life (no 
males in the family had the trait before his son/s exhibited it). Of course 
in this case the replication errors were maladaptive. 

Therefore is you're a young woman and you want your children to have a 
greater chance of having novel genetic traits (beneficial or otherwise) - 
find yourself a sugar daddy. :) 

I imagine this is similar for other species where ovae aren't continually 
produced in females, and where the males have long reproductive 'careers'. 

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Dann Pigdon
GIS / Archaeologist              http://geo_cities.com/dannsdinosaurs
Melbourne, Australia             http://heretichides.soffiles.com
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