Under the pale light of a laboratory flow hood, clad in a cleanroom suit, hat, and booties, Sarah Neumann gingerly unfolds an aluminum foil packet. An irislike pattern in dark brown powder reveals itself on the surface inside. It’s a fingerprint of sorts: Separate a mushroom cap from its stem and wrap it, gills down, in foil overnight, and the next morning you get this. For mycologists collecting samples from the wild, spore prints like these are aids to identification. For Neumann, whose work is in cultivation, they are repositories of genetic information.
In this case, the print belongs to a species called Psilocybe cubensis. Scattered in rich soil, or, better yet, manure, these genetically unique dots will develop into networks of delicate, branching threads called mycelium. Feeding on decomposing organic matter, the mycelium will eventually send up fruiting bodies—the familiar capped forms most of us know as mushrooms—laden with a new generation of spores. For reasons that remain mysterious, the fruiting bodies of P. cubensis and some of its fungi cousins also carry another cargo: chemicals that interact with the neurotransmitter receptors of the human brain to dramatically unmoor us from everyday perception and cognition, in ways that can feel like a waking nightmare, an awe-inducing glimpse of the universe’s most basic truths, or both.