From the article...
Isn't it an amazing coincidence that not only human life, but animal life as well, evolved exactly the same way on different planets light-years apart?
So even though we can't find existence of any kind of similar life outside of Earth, we're supposed to believe that Caprica evolved in exactly the same way, with humans looking identical as us (and sounding it, too) and even animals (like those pigeons we saw so much of in the final episodes) being the same? With the only real differences between us and them being that they liked to cut the corners off of their paper goods and say "frak" instead of our preferred F-word? And that the original 13th tribe also had a society that looked remarkably like ours, but with humanoid Cylons thrown into the mix? What. Are. The. Odds. Wasn't this supposed to be a science-fiction show?
If he thought about it a little more, he'd probably come up with a better answer. Maybe humans were transplanted to different worlds at some point in the past. Or maybe they moved around on their own in some past cycle. Also, their societies look the same because they were created out of the same "collective unconscious". To be fair though, that was explained by Moore and wasn't actually in the show. However, what was in the show was the whole "it happened before and it'll happen again" theme. I think that's a good enough way to explain why the same society keeps popping up again and again if you're not into examining the issue too deeply.