Watching a flock of city pigeons in flight can be mesmerizing. Here is my first attempt to capture a flock in flight, wheeling and circling over 110th Street and Broadway. Is it my imagination or does the flock grow, attracting other birds to fly with it as if by centrifugal force? Look closely at around the 35 second mark and then again around 42 seconds. Strange and wonderful.
And for a more spectacular vision of birds in flight, watch this video of a murmuration of European starlings soaring above the River Shannon in Ireland.
Starlings frequently gather in huge flocks, and then fly together, making incredible patterns in the sky. For another look with a bit of an explanation, watch the longer video below from England.