> > On the other hand, calculations by Francisco Ayala using the same
> > coalescent theory suggested that the human effective population size
> > (number of reproductively active individuals in a population)
> > never became
> > smaller than 50 individuals since the divergence from chimps. This is
> > inconsistent with the idea of a very strong populational bottleneck with
> > only one active female.
>
> No one ever believed that there was only one active female--even the
> advocates of mtDNA Eve. She just happened to be the only one who left her
> mtDNA to us. There was an entire population of women when mtDNA Eve was on
> earth--she wasn't the first. She was a descendant of the real Eve. One can
> see this effect in family names on Pitcairn Island. They started with 6
> family names. Today, due to men not leaving male offspring, they are down to
> 3 surnames in only 200 years. The y-chromosome structure on Pitcairn Island
> would reflect this. They didn't start with 3 males, though the evidence
> could not be used to prove the existence of the other 3.
>
If one believes in a literal *biblical* Eve, that would have been an
instantaneous speciation event with would cause a severe populational
bottleneck. That would have to be detectable using coalescent theory.
Marcio
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