Synchrony

There's a tendency in nature for things to fall into the same rhythm.

Schools of fish and flocks of birds turning on a dime without a leader. Two pendulum clocks set near each other begin falling into identical swings.

This is called synchrony, and perhaps the most fascinating example of it is the newly discovered instances of thousands of fireflies flashing their lights in nearly perfect unison (within a tenth of a second) in the Smoky Mountains in eastern Tennessee. This phenomenon has never before been documented in the Western Hemisphere; it has previously been observed only in Southeast Asia.

Check out an article here. Captivating!