I mentioned this in a thread attempting to prove someone wrong after they stated they believed humans weren't older than 6000 years. or something like that. I had remembered reading about a discovery in South America containing some primitive tribe or civilization that dated to, I cannot remember accurately, but over 20,000 years old.

I also speculated, and am serious about this, that man could have originated in the New World, after which he migrated to what we know as the Old World. If that isn't true, and it was in fact the other way around, then I definitely believe that humans crossed the land-bridge BEFORE the breakup of the last ice age, which was roughly 12,000 years ago.

I think there is a LOT of history relating to our origins that we have yet to discover. I have even thought about the fact that there may be some type of coverup, after reading about certain artifacts that have been found, for example like those in the area of the Grand Canyon, that we seem to know nothing about.