The Synchronous Fireflies! Only visible in the Great Smoky Mountains & Southeast Asia, and I just had the best week viewing this awe-inspiring light show! The synchronous fireflies of the Great Smoky Mountains are one of nature’s most dazzling light shows — and a rare biological phenomenon. These are Photinus carolinus, a species of firefly known for their ability to flash in unison. Most fireflies blink at random, but these synchronize their light patterns — creating rhythmic waves of glowing a