Psy­che­delic Ori­gins

Note­wor­thy

Magic mush­rooms are ex­pe­ri­enc­ing a resur­gence in pop­u­lar­ity. His­tor­i­cally val­ued for their psy­choac­tive prop­er­ties, psilo­cy­bin–con­tain­ing mush­rooms are now stud­ied as po­ten­tial al­ter­na­tive treat­ments for de­pres­sion, anx­i­ety, post-trau­matic stress dis­or­der (PTSD), and ad­dic­tion. The best-known psy­che­delic mush­rooms is Psilo­cybe cuben­sis, which is grown world­wide for recre­ational and med­i­c­i­nal pur­poses. 

But the ori­gin of this mush­room is an enigma. Did it orig­i­nate in Africa and was then in­ad­ver­tently in­tro­duced in the Amer­i­can con­ti­nent with cat­tle in the 1500s? Newly pub­lished find­ings sug­gest oth­er­wise. 

A group of sci­en­tists from the US and Africa col­lected sam­ples of mush­rooms re­sem­bling P. cuben­sis in Zim­babwe and South Africa. Us­ing analy­sis of con­served ge­netic loci, they com­pared these sam­ples with known type spec­i­mens. They found that the sam­ples from Africa cor­re­sponded to a dif­fer­ent, newly dis­cov­ered, species, Psilo­cybe ochraceo­cen­trata, which di­verged from P. cuben­sis about 1.5 mil­lion years ago. Both of these species rely on dung for spore dis­per­sal, a trait likely in­her­ited from their com­mon an­ces­tor. This new sce­nario sug­gests that a split into sep­a­rate lin­eages oc­curred long be­fore cat­tle do­mes­ti­ca­tion, likely due to a rare founder event that es­tab­lished P. cuben­sis in the Amer­i­cas, fol­lowed by ge­o­graph­i­cal iso­la­tion.

In ad­di­tion to un­cov­er­ing in­for­ma­tion on the ori­gin of do­mes­ti­cated P. cuben­sis, this new study pro­vides novel ge­netic re­sources for re­search on psy­che­delic mush­rooms.