A whole mangrove forest, lighting up all at once, plunging into darkness, then lighting up all again – in near-perfect synchrony. How do thousands of fireflies coordinate with each other? Who is the conductor of this silent symphony?

The fireflies phenomenom is astonishing. The web page http://ncase.me/fireflies/ provides an amazing explanation of this history and mechanics around it.

Let's create virtual fireflies using multiple Circuit Playground! The NeoPixel ring provides the flash, the light sensor can detect it and we can tie it all up with a bit of code in the Microsoft MakeCode code editor. Let's get started!