You have giant golden civilizations down there with the Incas, the Aztecs, and the Mayans that just putter out. They putter out because they don't have access to new technology or they don't have access to trade routes and they don't have cultural diffusion because they're trapped by water on either side. And they have the Andes Mountains. Then they have the Amazon jungle. So when you have all of that geography, Africa as well. Africa is trapped by oceans on either side. You have Europe in the north, but still the same.