Wizard Population (was: Wizarding Genetics)

[Mike]

No: HPFGUIDX 183711

> Catlady wrote:
> 
> My theory has a subset which can be rejected without rejecting
> the rest of the theory, that there is a set number of people in
> this world with wizarding powers.
>  -<snip>-
> 
> *** One thing this sub-theory needs is a reason why the number of
> people with wizarding magic, after growing along with the rest of
> the human population for many many millennia, would suddenly become
> fixed at a certain number.

Mike:
I agree with the multiple magical gene theory. That one makes sense 
to me. I could even be convinced that two magical people (James & 
Lily) produce offspring (Harry) with a kind of super-magical gene, 
like a mm-mm. So Harry could marry a Muggle with an MM gene-set and 
still he would be guaranteed one generation more of magical 
offspring. That is, he would contribute a mm instead of just a single 
m, which would crowd out the M that his Muggle wife contributed. This 
is kind of a reverse to your hybrid vigor.

But, though I go along with your your limited number of magicals sub-
theory as a general postulation, you've stated the problem with this 
theory in specific. I have a different take on the reason for limited 
magicals. Try this one on for size. ;-)

When the magical genes mutated into being in pre-history, the 
humans/wizards of that time didn't know or understand their magic. 
They continued to live amongst and intermarry with non-magicals and 
the occasional other magical. Sometime around 1000 BC, magicals 
started to learn how to harness their magic abilities. This is also 
when magical men (protowizards) started seeking out magical women 
(protowitches) for procreation. Thus beginning the consolidation of 
the magical genes. These would be the first "pure-bloods".

But magical folk continued to intermarry with non-magical folk, so 
though there was a subset of people trying to keep the wizarding 
genes within their own group, the rest continued to pass on the 
genes, but amongst an ever increase non-magical population. This 
meant that the wizarding population wasn't increasing along with the 
general population. With those wizards withdrawing to marry only 
other wizards, the reduced amount of magical genes mixing with Muggle 
genes was falling further and further behind the population curve. 
That and the Muggle carriers would continue to be diluted through the 
generations so that some strains/threads of magical genes just died 
out.

Upon the segregation of wizards through the statue of secrecy, 
Muggle-wizard unions would have dropped off precipitiously. Now, the 
percentage of muggles that carried the recessive magical genes would 
continue to decrease. Soon after this time, the subset that had 
continued with the pure-blood tract would have been intermarrying to 
such a degree that we would have started to see families like the 
Gaunts, at the end of their line. Ron was right. If the wizards 
didn't get outside of their closed society, intermarrying would have 
produced lots of Gaunt-like families.

Muggle-borns will continue to decrease as the chances of two 
recessive magical gene carriers meeting becomes more remote. That's 
if wizards stop seeding the Muggle population with their magical 
genes. As long as some wizards continue to marry Muggles at about the 
same rate as the pure-blood families die out, the wizarding 
population remains stable. 

Then again, Harry's great-grandchildren, if his progeny continues to 
marry other magicals, will probably be considered to be pure-blood. 
That's if that categorization survives.

Mike