Terence McKenna outlined the Stoned Ape Theory in his book "Food of the Gods: The Search for the Original Tree of Knowledge," published in 1992. In the book, McKenna explores various aspects of human evolution, culture, and consciousness, and he puts forth the Stoned Ape Theory as a speculative hypothesis.
In essence, Terence McKenna proposed that the consumption of psychedelic mushrooms, specifically those containing psilocybin, by early hominids like Homo erectus, had a profound impact on their behavior and cognition. According to the theory, this alteration in behavior triggered a series of events that contributed to the evolution of modern humans. The enhanced cognitive abilities and social effects attributed to the consumption of psilocybin mushrooms are suggested to have provided an evolutionary advantage, ultimately leading to the development of human consciousness.
He suggested that around 100,000 BCE, Homo erectus encountered and incorporated Psilocybe cubensis, a species of psychedelic mushrooms, into their diet. According to McKenna, the consumption of these mushrooms had a transformative effect on the cognitive abilities and behavior of early humans, contributing to the development of language, culture, and other aspects of human evolution.
McKenna proposed that the rapid increase in brain size of Homo erectus, occurring between two million and 700,000 years ago, could be linked to the consumption of mind-altering substances, specifically psychedelic mushrooms. The idea is that the psilocybin in these mushrooms could have triggered cognitive enhancements, contributing to the evolutionary leap in brain size and, by extension, cognitive abilities.
The claim that the brain size effectively doubled during that time period is generally accepted by paleoanthropologists. However, attributing this specific increase to the consumption of psychedelics is highly speculative.
Theories about the factors influencing human brain evolution often involve a combination of genetic, environmental, and social factors. While the use of psychedelics in various cultures and their potential effects on consciousness are acknowledged, establishing a direct and causative link between the consumption of specific substances and evolutionary changes in the brain is challenging due to the lack of direct evidence from the archaeological record.
It's important to view the Stoned Ape Theory as a provocative and speculative hypothesis rather than a well-established scientific explanation for the evolution of the human brain. The theory has generated interest and discussion but remains a topic of debate within the fields of anthropology and evolutionary biology.
