Two days ago, a man in Raisbeck, a small village in Cumbria, England, posted a video of starlings flying together in a murmuration:

Now is the time of year when starlings gather to roost and sometimes deliver these massive undulating performances above the trees. They do so when a falcon or another threat is close.

Scientists have found that the starlings execute these large-scale flights by “scale-free correlation.” As a starling shifts, it cues exactly seven other starlings to shift in the same way, each in turn affecting seven more, and so on through the flock. No one can say why seven is the magic number. This is just how it works.

To us humans, it’s easy to forget that starlings are startled into this mesmerizing formation. In gathering, the starlings become something amazing to us, the watchers below (or online, where murmurations tend to affect seven watchers who post it and then affect seven more — just kidding.) The phenomenon astonishes, even viewed on a screen.

Another video of a starling murmuration posted by the same watcher, last winter:

—

Read “The Incredbile Science Behind Starling Murmurations”

View another murmuration by photographer Graham Catley (his photograph of a falcon intercepting starlings appears above).