The transition from early hominin to modern human is quite a leap, and some researchers believe that the development of complex cognition and sociality may have been accelerated by external factors. The "stoned ape theory" suggests that consumption of magic mushrooms by our ancient ancestors kick-started the expansion of our mental capacities. To date, this highly speculative hypothesis has no hard supporting evidence, yet a new article in the journal Frontiers in Psychology attempts to argue the case for this wild theory.
Penned by independent researcher José Manuel Rodríguez Arce and Dr Michael Winkleman from Arizona State University, the paper states that “hominin evolution occurred in an ever-changing, and at times quickly changing, environmental landscape and entailed advancement into a socio-cognitive niche.” In other words, the challenge of survival created a need for greater intelligence, cooperative communications, and social learning.
According to the authors, these traits are highly dependant upon serotonin, a neurotransmitter created from the amino acid tryptophan. However, as humans are unable to produce tryptophan, the researchers argue that the only way early hominins could have boosted their serotonin levels was by eating magic mushrooms.
To back this up, they point to recent studies that have hinted at the potential of psychedelics to treat mental health disorders such as depression, primarily by activating serotonin receptors and enhancing neural plasticity. They claim that the ancient consumption of these substances may have allowed for new modes of cognition to emerge while also facilitating the growth of our brains.
Taking things a step further, the authors explain that the ingestion of psychedelic plants may have encouraged social bonding among ancient hominins, generating euphoria and laughter while enhancing the capacity for storytelling and music. This, they say, helped to create certain pro-social tendencies that promoted group cohesion and aided survival.
While all of this may sound plausible, the fact remains that there is no solid evidence proving that early hominins consumed mind-altering substances. Despite this, however, the authors insist that “our hominin ancestors inevitably encountered and likely ingested psychedelic mushrooms throughout their evolutionary history.” They also point to archaeological evidence suggesting that prehistoric humans ate mushrooms, and claim that various types of fungi featured heavily in the diet of early humans.
In spite of these assertions, it’s important to note that this contentious theory remains unrefined and hypothetical. Recognizing this, the authors admit that the truth about whether or not early hominins ate magic mushrooms “will forever remain uncertain.”
Nonetheless, they insist that “psychedelics’ effects in enhancing sociality, imagination, eloquence, and suggestibility may have increased adaptability and fitness [of early hominins].”
“In particular, the interpersonal and prosocial effects of psilocybin may have mediated the expansion of social bonding mechanisms such as laughter, music, storytelling, and religion, imposing a systematic bias on the selective environment that favored selection for prosociality in our lineage.”
If they’re right, then it could mean that we owe our intelligence and social skills to a bunch of tripping primates.