THIS is AWESOME. In a nutshell, this theory by Terence Mckenna is based on the idea that apes ate psychedelic mushrooms (way back in the day) that enhanced their brains into the human brains that we have today. Magic mushroom evolution! For those of you that do not know about the stoned ape theory you can read on to watch/listen about it. It will BLOW your mind.
The Stone Ape Theory Explained
The animation of the theory: "This is a clip from Duncan Trussell's Comedy Central Pilot "Thunderbrain." The animation and voice over was by Will Carsola from daybyday (www.livedaybyday.com) and it was produced by RZO Hothouse"