Yesterday I posted on the resurrection of the “redheads going extinct” meme (as I noted, this story seems to cycle every few years). The current source is National Geographic Magazine, which doesn’t have the “article” online. I went to the bookstore and checked out the September 2007 issue, and a write up does exist about the redheads going extinct. Unlike the secondary sources it isn’t as sensationalist, and makes more than a passing nod to the Hardy-Weinberg logic from which the inference is derived.
That being said, the write up in National Geographic Magazine simply recycles older versions of this story which emerged a few years ago, and doesn’t add any new “data” or analysis. In other words, we have here a staffer who needed a short paragraph or two to fill up a page in National Geographic Magazine, so they googled around (or something that effect), and simply repeated claims made in the previous rounds of reportage. As I noted earlier, those claims were pretty much made up. So you have here a case where a non-story from a few years ago was picked up by National Geographic, and the imprimatur of such a high status publication repeating the story has resulted in the reemergence of the meme in the venues which originated it in the first place!
In any case, the numbers which are injected to add a layer of scientific plausibility were likely concocted by the original writers who repeated the meme. I am skeptical that even 1% of the world’s population has red hair; people of European descent form around 15% of the world’s population last I checked, so such a high world wide frequency implies that around 1 out of 10 people of European descent is a redhead. Doesn’t pass the smell test.