Why Bugs and Mushrooms Glow

Keep the Love Light BurningScientists say there are more than 2,000 types of fireflies worldwide, but only 24 species are known in Michigan (six fly by day and don’t light). The telltale blinking – which peaks in June up here – is sort of a Morse Code mating ritual. Males blink in a certain pattern; females blink back with a pattern of their own. They hook up, sparks ignite. But males beware: Some firefly females imitate the blink of females from another firefly species. When the male responds to her provocative glow, she kills and eats him. Men – so easy.

Mystical MixA smidge of luciferin. A dash of luciferase. A bit of oxygen. And voilà, you end up with oxyluciferin. On paper it’s only chemistry, but in practice it’s magic. The chemical process is what gives the glow – but no heat – to Northern Michigan’s fireflies and mushrooms, and other life forms all over the globe, including marine animals.

“Why the same process evolved in so many different groups is really hard to understand,” says Marilynn Smith, a mycologist who teaches at the University of Michigan Biological Research Station.

Magic MushroomsOmphalotus olearius An orangey cap in part accounts for this ‘shroom’s common name, the Jack o’ lantern, but so too does its nighttime show. The gills (on the cap underside) glow in faint, eerie green light. Look for them large and clumped at the base of rotting stumps. Damp nights in late summer or early autumn are best.

Panellus Stipticus
By day: Boring brown mushroom. By night: Marvelous, glowing belle. Look for Panellus Stipticus in tiered clumps on rotting wood. Mycologist Smith has taken pieces of wood with the mushrooms into her class, and they still glowed beautifully the next day.

Armillaria mellea
Stand once on a forest floor laced with the ephemeral glow of foxfire and you’ll never again dismiss the wonder of nature. Foxfire glows from its mycelium, which are thin strands, analogous to roots, that bring nutrients to the fungi. Foxfire glows so brightly that people have used it to mark nighttime trails. Look for this ringing the base of trees in late summer and warm, damp nights in early fall.
Fireflies ForeverFirefly season, so sadly fleeting. Unless you happen to score some AA batteries and jars of faux fireflies. (Yes, we noticed that the lights are orange, not blue-green like real oxyluciferase would be, but why get nerdy about it.) Search Google for “faux fireflies jar.” $15-$20 per jar.

Jeff Smith is editor at Traverse, Northern Michigan’s Magazine.[email protected]

Article Comments