Wikipedia

The stoned ape theory had been widely criticized by the greater scientific community. McKenna's theory was labeled as overly speculative by much of the academic community[9] and misrepresenting the studies of psychopharmacologist Roland L. Fischer, whose research was frequently cited by McKenna as evidence for the purported effects of the mushrooms on early humans. Additionally, many pointed to groups such as the Aztecs or various Amazonian tribes whose usage of psychedelic substances does not reflect any of the evolutionary advantages that McKenna argued would emerge from using psilocybin-containing substances.[10][11]

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