This is how I believe the series of events occurred.
I did some wake and bake then jumped into the shower. While taking the shower, I started thinking about how when the Flinstones took a shower, it was a woolly mammoth that shot water out of its trunk, and I thought about how awesome that would be if it happened in real life. Then that thought switched to me trying to remember what the dinosaurs, mammoths, etc looked like in the movie version. Then I thought..."Hey that movie wasn't actually so bad, who played Betty again? Wait, it was Rosie O Donnell right? WTF??"
so you see, it's not like I got into the shower and pictures of rosie popped up into the old noggin, there was a train of thought there.