I didn't say anything about the reasons for that shift - just that it was there, and surprised me.
And Wikipedia may be unreliable, but it's the best I can do without a very slow and thourough search that would take days... The point is that we need to be able to change our minds on minor points without huge amounts of effort.
There's a lot of background mess in our mental pictures of the world. We try and be accurate on important issues, but a whole lot of the less important stuff we pick up from the media, the movies, and random impressions. And once these impressions are in our mental pictures, they just don't go away - until we find a fact that causes us to say "huh", and reassess.
Here are three facts that have caused that "huh" in me, recently, and completely rearranged minor parts of my mental map. I'm sharing them here, because that experience is a valuable one.