And then humans saw critters killing and eating fresh meat, ergo those critters knew that was fresh meat! And then after those critters had gorged themselves and slunk off somewhere, those humans snagged some of that fresh meat and they said, CHOW! And then one time some Lightning set some trees and bushes and grass on fire and it cooked that meat, yeah, and those humans said, this stuff is damn Good! and then humans learned how to make fire by rubbing some sticks together.