Have mushrooms shaped human evolution?

There are many mysteries about human evolution, and many questions about how we came to be the thinking species we are today. The Stoned Ape Theory, also known as the Psychedelic Ape Theory, is a controversial hypothesis that suggests that psychoactive substances, specifically psilocybin mushrooms, influenced the trajectory of cognitive development of our prehistoric ancestors. The theory was first proposed by American ethnobotanist and mystic Terence McKenna in his 1992 book ‘Food of the Gods’. According to McKenna, as a result of desertification in Africa, people retreated into shrinking tropical forests, where they followed cattle herds whose manure attracted the insects he claims…