Human race spent most of the time on earth not knowing that round objects roll. amirite?

Could be if they all lived on flat land.

For what we know now that would seem the case, but I wouldn't bet on it. I'm sure some human saw a round rock roll down a hill somewhere. It just took a while to invent the wheel.

I doubt it....pretty sure it didn't take long to notice, from those number 2's on side of the hill.