From Wired Science::

“What makes possible the uncanny coordination of these murmurations, as starling flocks are so beautifully known? Until recently, it was hard to say. Scientists had to wait for the tools of high-powered video analysis and computational modeling. And when these were finally applied to starlings, they revealed patterns known less from biology than cutting-edge physics.

Starling flocks, it turns out, are best described with equations of “critical transitions” — systems that are poised to tip, to be almost instantly and completely transformed, like metals becoming magnetized or liquid turning to gas. Each starling in a flock is connected to every other. When a flock turns in unison, it’s a phase transition.

At the individual level, the rules guiding this are relatively simple. When a neighbor moves, so do you. Depending on the flock’s size and speed and its members’ flight physiologies, the large-scale pattern changes. What’s complicated, or at least unknown, is how criticality is created and maintained.”
http://www.wired.com/wiredscience/2011/11/starling-flock/

And another article from Wired Science:
“In particle physics, synchronized orientation is found in systems with “low noise,” in which signals are transmitted without degrading. But low noise isn’t enough to produce synchronized speeds, which are found in critical systems. The researchers give the example of ferromagnetism, where particles in a magnet exhibit perfect interconnection at a precise, “critical” temperature.”
http://www.wired.com/wiredscience/2010/06/starling-physics/