See also: Hinge moments These stray ideas are just tossed out here, and are not as well developed as ideas found in the Hinge Moments page. * New World Wheel. Possibly a non-started for Incas, Mayans, etc due to jungle and mountainous terrain. Something interesting could develop if you could contrive a way for the Zuni to get the wheel. Or perhaps the failed Norse settlements spread the wheel to northern tribes. Lots of possibilities ... * Massive volcano does not erupt in 535 causing prolonged world wide drought. In the book "Catastrophe" Davis Keys argues that a massive volcanic eruption changed the global environment for several decades and drastically altered history throughout the world.