Well for starters I'd say my basic point is that its foolish to assume nothing came before what we do know about. There could have been past human civilizations

Well for starters I'd say my basic point is that its foolish to assume nothing came before what we do know about. There could have been past human civilizations, with enough time any natural building materials would effectively vanish. More interesting to me, though, would be non-human civilizations that could have existed well before humans ever came around. I don't consider animals to have civilizations simply for having complex groups (ants or bees, for example). Though separately they do absolutely have emotions, family bonds, and long memories. My cows have proven that, each one is a different personality with their own clicks among the herd, and each cow treats the me and my wife differently so its not like "this one's always mean, this one wants to be petted" etc.