A mosquito swarm resembles a living cloud — hundreds of bodies circle together, but no one lines up or mimics a neighbor's movements like starlings or fish. For a long time, it was unclear what held such unity together. The authors of a new study suggested that the insects communicate by sound. Each individual hears the hum of many wings around it and flies toward where the hum is louder — toward the center of the 'sound cloud.'
The model turned out to be simple and powerful. It reproduced a strange dance sometimes seen in nature: a pair of mosquitoes breaks away from the swarm and spirals around each other. The math showed that such paired separation is a path to the collapse of the entire aggregation. And here, an unexpected ally of order comes into play — random noise. Small disturbances in the signals prevent pairs from getting too close, and the swarm remains intact.
Thus, nature uses collective behavior without a leader and without complex rules. It is enough to listen to neighbors and fly toward the common hum. Random glitches do not destroy the system but, on the contrary, heal its weak spots, like a slight tremor in a surgeon's hands sometimes makes the incision more precise.
The wingbeat frequency of mosquitoes is about 500–600 hertz, almost the note 'D' of the second octave. A swarm sounds like an out-of-tune orchestra of thousands of such 'D's.