Magic mushrooms likely developed their psychedelic properties as a defense against predators

Psilocybin is the naturally occurring substance that puts the “magic” in “magic mushrooms.” Their psychedelic properties have made them popular for therapeutic, spiritual, and recreational use — for humans at least. But their biological purpose, as well as their evolutionary origins, has remained a mystery. Until now. A study, published in Evolution Letters, has suggested that mushrooms may have begun producing psilocybin as a defensive measure against predators.

To arrive at this conclusion, researchers from The Ohio State University worked off the idea that the genes responsible for psilocybin weren’t passed through a biological lineage. After all, there are dozens of species of magic mushrooms but no single family. Instead, the psilocybin genes were most likely transmitted via horizontal gene transfer. This is the movement of genetic material from one species to another in lieu of parent to child. According to Jason Slot, lead study author and assistant professor of fungal evolutionary genomics at The Ohio State University, horizontal gene transfer usually occurs as a result of environmental stressors.