Psychedelics, Sociality, and Human Evolution

Abstract

Our hominin ancestors inevitably encountered and likely ingested psychedelic mushrooms throughout their evolutionary history. This assertion is supported by current understanding of: early hominins’ paleodiet and paleoecology; primate phylogeny of mycophagical and self-medicative behaviors; and the biogeography of psilocybin-containing fungi. These lines of evidence indicate mushrooms (including bioactive species) have been a relevant resource since the Pliocene, when hominins intensified exploitation of forest floor foods. Psilocybin and similar psychedelics that primarily target the serotonin 2A receptor subtype stimulate an active coping strategy response that may provide an enhanced capacity for adaptive changes through a flexible and associative mode of cognition. Such psychedelics also alter emotional processing, self-regulation, and social behavior, often having enduring effects on individual and group well-being and sociality. A homeostatic and drug instrumentalization perspective suggests that incidental inclusion of psychedelics in the diet of hominins, and their eventual addition to rituals and institutions of early humans could have conferred selective advantages. Hominin evolution occurred in an ever-changing, and at times quickly changing, environmental landscape and entailed advancement into a socio-cognitive niche, i.e., the development of a socially interdependent lifeway based on reasoning, cooperative communication, and social learning. In this context, psychedelics’ effects in enhancing sociality, imagination, eloquence, and suggestibility may have increased adaptability and fitness. We present interdisciplinary evidence for a model of psychedelic instrumentalization focused on four interrelated instrumentalization goals: management of psychological distress and treatment of health problems; enhanced social interaction and interpersonal relations; facilitation of collective ritual and religious activities; and enhanced group decision-making. The socio-cognitive niche was simultaneously a selection pressure and an adaptive response, and was partially constructed by hominins through their activities and their choices. Therefore, the evolutionary scenario put forward suggests that integration of psilocybin into ancient diet, communal practice, and proto-religious activity may have enhanced hominin response to the socio-cognitive niche, while also aiding in its creation. 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.

Mycotherapy: Potential of Fungal Bioactives for the Treatment of Mental Health Disorders and Morbidities of Chronic Pain

“…LSD was also a psychedelic compound highly researched in the 1950s until the Controlled Substances Act was introduced in 1970 [ 72 ]. Like psilocybin, LSD has activity on brain processes involved in cognition, emotion, and perception via affinity for serotonin receptors [ 101 ]. LSD is an agonist of 5-HT with high affinity for 5-HT2A and 5-HT2C and is small enough to pass the BBB being approximately 100 times more potent than psilocybin [ 73 ].…”

Psychedelics and fNIRS neuroimaging: exploring new opportunities

“… 11 Given these intense mind-altering properties, plant-derived psychedelics have been used for millennia for spiritual and medicinal purposes. 21 , 22 …”

Psychedelics: Their Limited Understanding and Future in the Treatment of Chronic Pain

“…Similar to Mesoamerican societies, the ancient Egyptians left behind artworks depicting mushrooms. Our hominin ancestors invariably encountered and likely ingested psychedelics [ 3 ]. Hence, ancient history was influenced by psychedelics.…”

“…LSD was produced in a lab in 1943 [ 2 ], while others are extracted from plants and fungi. Our ancestors likely ingested psychedelic mushrooms from the genus Psilocybe since the Pliocene (beginning 5.3 million years ago [mya]), when semi-arboreal hominins intensified foraging activity on the ground [ 3 ]. There is evidence of self-medication among the primates and Paleolithic humans [ 4 ].…”