Coffee is the most widely consumed mind-altering plant product in the world. The human species arose in or near the Rift Valley in East Africa, the northern edge of which abuts the forests of Ethiopia in which the coffee plants originated. The drunk monkey hypothesis proposes that human consciousness was born when our ancestors ingested fermented grapes. The stoned ape hypothesis suggests that the consciousness is due to proto humans consuming magic mushrooms. In the first half of two-part episode, Mark Plotkin suggests that the human mind developed when these primates ate coffee berries, whose caffeine inspired both their thinking and their creativity.