Synchronized swimming: how do fireflies manage to blink in unison?

The synchronous flickering of fireflies is a mystery that scientists still can't solve completely. Why and how do thousands of fireflies arrange a "light show"? Do they have a "conductor"? How do they maintain the rhythm? And why do they do it? These questions have occupied the minds of biologists for almost a century.

However, the answer to the question why they do this is still obvious to researchers. By the end of the 60s of the last century, biologists noticed that fireflies flash not only simultaneously, but also in a certain rhythm and pace. In the course of research, it turned out that the "synchronizers" in the group are all male individuals. And so they attract the female during the mating season. Because if the female sees scattered flashes appearing here and there, the probability that she will respond to the call is only 3-10 %. If the males blink synchronously and with the inherent pattern of light, this probability increases to 83 % — the female will easily identify the "suitors" of her species and make contact.

But the answer to the question of how the synchronous glow begins is a little more difficult. During a long study and a series of experiments, it turned out that each individual Firefly in the group independently corrects the moments of its flickering. Each individual continuously sends and receives signals from outside, adjusting to them and shifting its own rhythm. That is, after seeing a signal from any other Firefly in the group, the male simply reconfigures its own flicker. The result is a spontaneous but impressive synchronism.

Biologists still do not know at what level the interaction between insects occurs. They are not intelligent, but they have an internal oscillator, like a metronome in the human heart. Presumably, this synchronicity is provided by nerve impulses.