Technically, isn’t it the number of X chromosomes that matters to colorblindness? It’s just that people with Y chromosomes almost always have one X chromosome, and people without them almost always have two.
You’re correct; we asked for Y chromosomes rather than X chromosomes because it’s way easier to have an extra X and not know it than to have a Y and not know it. So if we ask about Y, we can rough-sort into “probably XY” and “probably XX” groups and then look at the statistics for chromosomal deviations within those groups.
I thought I did. Now that I’ve followed your link, I realize that even if it were less common, it would probably only be marginally so, so I withdraw my comment above.
Technically, isn’t it the number of X chromosomes that matters to colorblindness? It’s just that people with Y chromosomes almost always have one X chromosome, and people without them almost always have two.
You’re correct; we asked for Y chromosomes rather than X chromosomes because it’s way easier to have an extra X and not know it than to have a Y and not know it. So if we ask about Y, we can rough-sort into “probably XY” and “probably XX” groups and then look at the statistics for chromosomal deviations within those groups.
… especially if they’re responding to xkcd polls.
You have some reason to believe that Klinefelte’s syndrome (XXY) is less common among xkcd readers than among the general population?
I thought I did. Now that I’ve followed your link, I realize that even if it were less common, it would probably only be marginally so, so I withdraw my comment above.