Starling flock magic explained. Video and rules. UPDATE

By their thousands, starlings swarm in fluid arabesques. The video below shows ten million starlings over Rome.  A 3D film record of this same flock was analyzed by Hemelrijk's group at the University of Groningen.

Researchers Unravel the Magic of Flocks of Starlings
A few simple rules and massive number crunching explains how they self-organize. Thousands of individual starling paths were mapped in three dimensions as they flew above Rome's train station.
The birds are attracted to their neighbors, thus they regroup after a disturbance.
They like to fly in the same direction as their neighbors.
The birds fly at a fixed speed, thus they lose their position whenever a corner is turned.
They pay attention unequally to six or seven nearest neighbors, favoring those to the left and right.

For comparison:  Video of an immense swarm of locusts. (the first few seconds of video are just the warm up). Shapes keep reforming with linear features which suggest rules one and two apply and the behaviour of the locusts immediately in front is more important than the ones to the side.

Added: Video and charting showing 10 robot UAV's flocking together using various rules. (The voice over is particularly irritating but the images are fine.)

UPDATE:  New rule added:
The mystery behind the movements of flocking starlings could be explained by the areas of light and dark created as they fly, new research suggests. The research found that flocking starlings aim to maintain an optimum density at which they can gather data on their surroundings. This occurs when they can see light through the flock at many angles, a state known as marginal opacity. The subsequent pattern of light and dark, formed as the birds attempt to achieve the necessary density, is what provides vital information to individual birds within the flock.

Agent based simulation fo a flock of starlings under predation from a hawk. Using the Hybrid Projection Model, developed by Daniel Pearce