A flock of birds in the human world

For a very long time I have been fascinated by birds flying in a flock.
There is something very magical about how a flock looks in the air, with seemingly dense patches of birds and more open spaces in other spots.

Even though a flock keeps flying in more or less the same direction, the smaller patches may sometimes fly in a totally different direction. This is what makes a flock such a wonderfull thing to watch. Here is a beautifull example found on youtube:

A number of years ago I saw a geeky scientist on tv. He had played aroud with a graphic simulation on a computer (this is a long time ago ;-) He programmed it so that a number of dots on the screen moved at a certain speed within a field. The dots also had to maintain a specific distance. To his surprise the result was a flock of pixels! They behaved in the same way as a flock of birds!