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Bioluminescent Organisms: 3 Living Lights

According to folklore, the soft light emitted by bioluminescent organisms is magical. In reality, the eerie glow results from a chemical reaction–but it still looks enchanting on a moonless or cloudy night. Here's where to glimpse these living light bulbs.

On early–summer nights in pristine southern Appalachian woodlands, tiny male blue ghost fireflies–each about the size of a grain of rice–emerge en masse to beckon to wingless females in the leaf litter below. Unlike the common lightning bug, blue ghosts don’t flash; instead, they emit a steady blue or green glow for 30 to 40 seconds at a time. When swarms of the flies drift together above the forest floor, nearby hikers might imagine they’re standing calf–deep in an airy, luminous sea. Top spot: DuPont State Forest, NC;

The rare but dazzling fungus gnat resembles a miniature crane fly as an adult, but as a larva, it behaves more like a spider with a built–in LED. On summer days, colonies of hundreds of the half–inch–long glowworms spin sticky, quarter–size webs across depressions in streambanks, cave entrances, and rocky seeps. By night, they lurk behind their snares, glowing a vivid blue to lure flies and midges that they quickly subdue with a paralyzing, venomous mucous. Top spot: Cumberland Trail, Black Mountain, TN;

Also known as fairy fire and will–o–the–wisp, these forest fungi lend their ghostly glow to the rotting trees and stumps on which they thrive. Mycologists theorize that the light is a reproductive strategy, attracting insects that spread the fungus’s spores. In some species, such as the honey mushroom, the threadlike mycelia (or “roots”) are the most luminous parts; in others, like the bright orange Jack O’ Lantern, the mushroom’s gills cast a dim green light. Top spot: Larch Mountain Trail, Columbia River Gorge, OR;

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