What starlings have to teach us about the wisdom of crowds

Every evening, as dusk soaks the sky, the starlings have been murmurating. They take to the air in small groups at first—moving as one, in quick, lively movements—before these droplets inevitably coalesce into a larger, liquid flock that flows through the sky, stretching apart then rebounding, undulant, pulsating. They do it every night, but every time it catches me unawares: a thousand tiny bodies coming together as one, each bird a point in a sheet of rolling, rippling life.

As the display draws to a close, they whirl down in a vortex into the branches of a tree, like water down a plughole, and it is as if it never was. But they’ll be back tomorrow: that breathy rush of soft forms moving fast in the gaps between the houses.

We don’t know why they do it, although we can guess: it’s thought that grouping together allows them to exchange body heat, and information on feeding grounds. Their wheeling, balletic movements also offer some protection from predators like hawks and falcons—not unlike those flashing shoals of silver fish you’ve likely seen on nature programmes: small fish like sardines or anchovies will form a dense, spinning sphere known as a “baitball” when hunted.

There’s a point at which collective behaviour crosses into collective intelligence. In starlings it comes early. Even a group of 10 moves in tight formation; and in a murmuration millions of birds strong, they might fly less than a body-length apart, at speeds of 50mph, blowing over the landscape as a fast-moving cloud, without ever colliding.

One early researcher, groping for an explanation, suggested telepathic abilities (“thought transference”), but more recent studies have identified that the mass-movement is likely governed by a simple rule, writ large: the birds track the movements of their nearest neighbours and adjust their own to match, and this—multiplied many times over—has the power to create the vast, ever-changing spectacle of the murmuration.

Simple units, acting en masse and in concert, create complex phenomenon. Many insects have fascinatingly intricate social systems, which when viewed as a whole effectively comprise a “superorganism” of tiny tesserae. Army ants, when migrating, nightly build a “bivouac” or nest of their own bodies. Worker ants linking their legs together to create a net-like skin, within which the queen and her larvae are protected, a behaviour as remarkable as it is horrifying to watch.

The power of collective intelligence is of great interest to those working in both artificial intelligence and political science: AI experts see potential for vast, co-operative computer networks, while politicos are focused on what collective decision-making can tell us about democracy. For what else is democracy but a country-worth of humans making individual decisions based on local conditions?

If you, like me, have been throwing up your hands in frustration at the current political morass, you might find solace in a recent study from Oxford University, which found that—against expectation—incompetent leaders of a flock of homing pigeons would be swiftly overruled. The exact social mechanism is not understood, noted the study lead. “However, we can speculate that it may be due to either misinformed flock leaders doubting their own abilities… or the flock members recognising weakness in the leader and taking more control themselves.” Talk about taking back control.