Syncing Fireflies

Synchronous fireflies in a forest

Have you ever seen so many fireflies? These fireflies are different from the ones you might see on a summer night. They are called synchronous fireflies because they “sync” their flashing and all flash at the same time.

Synchronous fireflies are rare in the United States. You can see them in only a few places. The biggest population lives in Great Smoky Mountains National Park in Tennessee. Every year, hundreds of people travel to the park to see them.

Visitors hike to a viewing spot in the woods. Once it gets dark, park rangers instruct them to keep quiet and turn their flashlights off. Soon, the light show begins! Thousands of fireflies flash their lights for a few seconds. Then, they all stop. The sudden stop in flashing creates complete darkness. After a few more seconds, the fireflies all flash again.

The flashing pattern is their mating display. The males fly around and flash. Then females flash their lights in response. It is one of nature’s amazing light shows!

Brilliant Beetles

Did you know that fireflies are beetles? Most fireflies have wings and make light with a part under their abdomen. The light is caused by a chemical reaction. It is described as “cold light” because it gives off almost no heat.

What Do You Think? Why do you think park rangers tell visitors to turn their flashlights off?

Photo Credit: (t)Nori Yuasa/500px/Getty Images, (b)Anita Patterson Peppers/