Scale-invariant bird flocks in critical state

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Rome is famous for its huge flocks of starlings that swerve through the evening sky as if directed by a collective intelligence. While these spectacular displays have fascinated Romans since ancient times, they have yet to be described effectively by a mathematical model.

Now physicists in Italy have analysed 3D photographs of the Eternal City's famous flocks using techniques borrowed from statistical mechanics. They found that a change in direction of one bird can affect the behaviour of all its companions – regardless of the size of the flock. This, argue the physicists, ensures a maximal response to environmental perturbations such as attacks by predators.

http://physicsworld.com/cws/article/news/43118

(tho critical, birds may not actually explode)

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The photo looks like a Lorenz attractor