Harry Potter Genetics again
Nov. 4th, 2015 05:30 pmI remember people pointing out that Harry Potter genetics didn't make a whole lot of sense. The observed traits seemed to be:
* Children of muggles were occaisionally wizards
* Children of wizards were almost always wizards, but sometimes had weak magic, or very rarely nonexistant magic.
It seemed roughly like, magic arose in muggle populations a bit like recessive carriers breeding together, but once someone had it, it was dominant.
Although now I think about it, if the wizarding population is "thousands", maybe those two rates are actually the same, just that the population of the UK is that much bigger than the wizarding population.
I didn't think about it too hard. It was clear how it was _intended_ to work, which to me is the important thing. I didn't care too much whether the worldbuilding was genetically plausible, when obviously magic flouted the rules in so many other ways. In fact, I think it was fairly good worldbuilding, in that the rules were explained clearly but without overemphasis at the beginning, both implicitly and explicitly, and then background events supported them throughout.
And I also remember an article that said some genetic traits could work like that, although I don't remember the details.
And then Liv said something which was obvious to her but I'd never thought of. That she assumed that it was a _recessive_ trait, but that wizards primarily had children with other wizards.
And I realised that could be true -- we have one (or more?) examples of mixed marriages, but we don't actually know if those are common. (I infer Rowling would like to think so, because it's more inclusive like that, but I don't remember it actually being stated, and it would obviously be impractical in many ways -- most wizards don't live in muggle society much at all).
If so, everything mostly works. Muggle-born wizards happen because of recessive carriers breeding together. Wizard-wizard marriages always produce wizard children, except when something else goes wrong producing a squib. And the wizard community, especially purebloods, but others too, tend to inbreed. And there are occasional mixed marriages which have approx 50% squibs, but they're not common enough to be talked about, and the squibs have an out into muggle life via their muggle parent if they want.
She said it was similar to how some real-life communities, like deaf communities, or Ashkenazi Jews, often accumulate recessive genetic traits.
And I had all the knowledge to be able to put that together in theory, but not enough experience that I actually _did_. I didn't notice that one of my assumptions, even if likely true on balance, wasn't as well supported as the others, and if I let go of it, everything could work. Which reminded me, even when you're sure, you can be _too_ sure.
* Children of muggles were occaisionally wizards
* Children of wizards were almost always wizards, but sometimes had weak magic, or very rarely nonexistant magic.
It seemed roughly like, magic arose in muggle populations a bit like recessive carriers breeding together, but once someone had it, it was dominant.
Although now I think about it, if the wizarding population is "thousands", maybe those two rates are actually the same, just that the population of the UK is that much bigger than the wizarding population.
I didn't think about it too hard. It was clear how it was _intended_ to work, which to me is the important thing. I didn't care too much whether the worldbuilding was genetically plausible, when obviously magic flouted the rules in so many other ways. In fact, I think it was fairly good worldbuilding, in that the rules were explained clearly but without overemphasis at the beginning, both implicitly and explicitly, and then background events supported them throughout.
And I also remember an article that said some genetic traits could work like that, although I don't remember the details.
And then Liv said something which was obvious to her but I'd never thought of. That she assumed that it was a _recessive_ trait, but that wizards primarily had children with other wizards.
And I realised that could be true -- we have one (or more?) examples of mixed marriages, but we don't actually know if those are common. (I infer Rowling would like to think so, because it's more inclusive like that, but I don't remember it actually being stated, and it would obviously be impractical in many ways -- most wizards don't live in muggle society much at all).
If so, everything mostly works. Muggle-born wizards happen because of recessive carriers breeding together. Wizard-wizard marriages always produce wizard children, except when something else goes wrong producing a squib. And the wizard community, especially purebloods, but others too, tend to inbreed. And there are occasional mixed marriages which have approx 50% squibs, but they're not common enough to be talked about, and the squibs have an out into muggle life via their muggle parent if they want.
She said it was similar to how some real-life communities, like deaf communities, or Ashkenazi Jews, often accumulate recessive genetic traits.
And I had all the knowledge to be able to put that together in theory, but not enough experience that I actually _did_. I didn't notice that one of my assumptions, even if likely true on balance, wasn't as well supported as the others, and if I let go of it, everything could work. Which reminded me, even when you're sure, you can be _too_ sure.