Fun­gal Stars in the For­est Dark

This is the third post for this year's Week of the Fungi on STC, a spo­radic un­der­tak­ing. This an­nual fes­ti­val is our way to hail the start of the fall mush­room col­lect­ing sea­son in parts of our home ter­ri­tory (the north­ern hemi­sphere).

by Elio

Fungi, along with se­lected bac­te­ria and in­ver­te­brates, are in­cluded in the list of bi­o­lu­mi­nes­cent or­gan­isms. These fungi are pretty unique be­cause, un­like the other light-emit­ting or­gan­isms, fungi don't walk, swim, or fly. Thus, the usual ex­pla­na­tions for bi­o­lu­mi­nes­cence (e.g., at­trac­tion, re­pul­sion, com­mu­ni­ca­tion) do not seem to ap­ply. Dis­pers­ing spores is a cen­tral pre­oc­cu­pa­tion among mush­rooms, so one can guess that the light may facili­tate vis­its by an­i­mals that could help in this process. Plus, as Den­nis Des­jardin writes in a news item from the NSF, some may well glow to at­tract the preda­tors of in­sects that eat the mushrooms...befriend the en­emy of your en­emy!

Mycena lux­coeli, a Japan­ese fun­gus, pho­tographed by its own light. Source

So far, only 65 of the 85,000 species of fungi are known to glow. Look­ing for new bi­o­lu­mi­nes­cent species is some­thing one does un­der the cloak of dark­ness and, in Des­jardin's case, in deep Brazil­ian jun­gles. Just how you avoid get­ting bit­ten by who knows who, and, more im­por­tantly, how you keep from get­ting lost, is some­thing that you need to read for your­self in this ar­ti­cle. While you are wor­ry­ing about that, pon­der these other ques­tions posed by the au­thor: Why are there so few lu­mi­nes­cent fungi? What is the mech­a­nism of lu­mi­nes­cence? When and how many times did lu­mi­nes­cence evolve in the fungi? Why do they glow?"

Mycena lu­cen­tipes, a Brazil­ian mush­room photo­graph­ed by its own light. Source