Unresolved
Psilocybin, by increasing visual acuity at low doses, provided adaptive advantages to early hominids that drove selection for larger brains.
Claim source
Food of the Gods, Chapter 2Current evidence · confidence: low
The specific claim about visual acuity at low doses has some support from studies on psychedelic microdosing showing enhanced pattern recognition. The evolutionary pressure claim requires evidence that is not available from the fossil record. The mechanism is theoretically possible; the evidence for it actually operating in early hominid evolution does not exist.Citation
Nichols (2016); current paleoanthropology literature [Source not found; under review]