Jun 14, 2011: I wonder how do they manage not to hurt their neighbors by flapping wings in such a dense pack?

By the way, I've read in news recently that synchronization of behavior in big swarms (insects, bacteria) is studied by scientists. They want to mimic the effective mechanism developed by nature and called “quorum sensing” for synching of robot swarms. That's another development making people closer to realization of the idea in Lem's science fiction — self-organizing swarms of small relatively simple robots which is now called “swarm robotics”.

most likely, species Buzzer midge Chironomus plumosus