Synchronized Smokey Mountain Fireflies

Dylan Thuras is a guest blogger on Boing Boing. Dylan is a travel blogger and the co-founder of the Atlas Obscura: A Compendium of the World's Wonders, Curiosities, and Esoterica, with Joshua Foer.

So to contrast with the giant industrial holes and moon poop Josh and I have been posting about, I am going to highlight one of my favorite bioluminescent wonders in the world.

Happening right now, and for the next few days the Great Smoky Mountains of Tennessee will light up as P. Carolinus fireflies begin to blink in beautiful, astonishing unison. The fireflies, who can sense when their neighbor fireflies are flashing and attempt to flash before them, send waves of light to cascading down the Tennessee hillsides. One of the best spots to see them is in one small area, near the Little River Trailhead in Elkmont, TN.

Long thought to be an exclusively Southeast Asian phenomenon, the dazzling behavior was only discovered in an American firefly species (P. Carolinus) in 1992. The American fireflies were first brought to the attention of scientists by a reader of Science News, who thought it odd that an article on Asian firefly synchronicity mentioned nothing about the bugs near her own home. She wrote a letter to a Steven Strogratz, a Cornell mathematician who studies synchronization:

"I am sure you are aware of this, but just in case, there is a type of group synchrony lightning bug inside the Great Smoky Mountain National Park near Elkmont, Tennessee. These bugs "start up" in mid June at 10 pm nightly. They exhibit 6 seconds of total darkness; then in perfect synchrony, thousands light up 6 rapid times in a 3 second period before all going dark for 6 more seconds.

"We have a cabin in Elkmont… and as far as we know, it is only in this small area that this particular type of group synchronized lightning bug exists. It is beautiful."

In 1995, scientists confirmed the existence of the Great Smoky Mountain synchronized fireflies, and have subsequently discovered other populations in the Congaree Swamp in South Carolina and other high altitude locations in the Appalachian mountains. As this curious phenomenon remained undiscovered for years, it is quite possible that there are other varieties of fireflies blinking in unison throughout the United States, perhaps even in your own backyard.

More info on the Smokey Mountain fireflies here and here more info on bioluminescent spots around the world on the Atlas bioluminescent spots page.