|Walk Like a Fish|
New Yorkers normally roll their eyes, but they ought to take a closer look: watching these tourists interrupt the flow of traffic shows us how well pedestrians in our city usually move. This year I slowed down and observed them.
The study of pedestrian movement took off with the urban sociologist William H. Whyte, who in the 1970s recorded walkers’ behavior in the city, noting loitering and flirting; capturing the dynamics of bus-stop queuing; and analyzing how the throngs of people mostly managed to cooperate, instead of dissolving into a turbulent rumpus. What he found is how reliably pedestrians automatically adjust to one another’s behavior. Modeling this behavior is now a field of study, invoking everything from fluid dynamics to behavioral heuristics to describe how we navigate our sidewalks, swollen with people, without saying a word to one another.
Fred Kent, who worked with Mr. Whyte and founded a nonprofit called Project for Public Spaces, showed me how it was done as we walked together down a busy street. “We who know the city can kind of ...” and here he mimed the “step and slide” — a small movement out of the way of an oncoming walker. While striding forward, we turn ever so slightly to the side, pulling in our bellies and leading with the shoulder instead of the nose. This lets us barely brush against passing pedestrians, our hands to our torsos and faces turned away politely.
This is but one of the ways we adjust to being small fish in a big pond. Fish happen to be a good model for what we do: research on fish “traffic” management has led to the formulation of three simple rules they follow to avoid congestion while moving together with hundreds or thousands of other fish. The same rules explain the remarkable synchrony of flocks of birds, swarms of army ants and even mass migrations of wildebeests and whales.
First, avoid bumping into others (while staying comfortably close). What counts as comfortably close — the “personal” space an animal attempts to maintain between itself and others — will vary by species. Little brown bats roost tightly packed together, with full-body contact, and Emperor penguins are happy setting up shop a mere couple of flippers’ lengths from other birds, while humpback whales appear to prefer to stay more than a mile away from one another — still close enough to react to the behavior of those around them.