“Although hid­den from the na­ked eye, mi­croor­gan­isms are ac­tive in com­plex net­works of trade, swap­ping nu­tri­ents, hoard­ing re­sources and bar­ter­ing deals us­ing many of the same strate­gies hu­mans use to dom­i­nate mar­kets,” John­son said. 

“While we know such ‘bi­o­log­i­cal mar­kets’ ex­ist in na­ture be­tween cog­ni­tive [high­er] or­gan­isms—for ex­am­ple, when pri­ma­tes groom each oth­er in ex­change for food—it is dif­fi­cult to im­ag­ine mar­kets emerg­ing” on such a small scale.

Yet all or­gan­isms, in­clud­ing hu­mans, co­op­er­ate with ben­e­fi­cial mi­crobes, she not­ed. “For ex­am­ple, our gut bac­te­ria give us vi­ta­mins and nu­tri­ents and are cru­cial to our well-being,” John­son said.

Mi­crobes al­so co­op­er­ate with plants. John­son and the oth­er au­thors dis­cuss di­verse eco­nom­ic strate­gies em­ployed by mi­crobes, in­clud­ing avoid­ing bad trad­ing part­ners, sav­ing for a rainy day and build­ing lo­cal busi­ness ties.