How thousands of fireflies flash in time with no leader: pulse-coupled oscillators

30seconds
On riverbank trees in Southeast Asia, thousands of male fireflies flash together, with no leader and no shared clock. Each insect is just a small timer that nudges itself toward any flash it sees.
Scatter a meadow of simulated fireflies, then slide the strength of their reaction and the size of the crowd. Tap the field to wave a lantern and watch the chart of flashes turn into tall, narrow spikes as the rhythm takes over.
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