Not only living socially, but being able to pass learned information from one generation to another ignited a technological quantum leap for mankind. We can access information from previous generations. Each new generation does not have to start from ground zero.
Rufus
As to the question of the earth's orbit, it could have been knocked off of a previous axis by some sort of impact. This would have shifted the poles. I recall reading years ago about a frozen mammoth that was found with fresh grass and blooming flowers in it's gut. They were fast frozen and...
I am not really sold on that "Out of Africa" idea. I suspect that is just where fossils were best preserved. Time will tell on this issue. I suspect as we begin to look elsewhere we will find contrary evidence.
Rufus