Have you ever watched a flock of birds fly, turn, and dive in what seems like perfect unison? You might look at this and assume that a lead bird is determining the directions of the flock, or that they are collectively responding to small changes in the wind.
All of those are good guesses, but physicists from the Università Sapienza in Rome have used computer simulations to determine what they believe is the real reason for this amazing coordination.
Starling murmuration
A murmuration is the collective noun of a flock of starlings. It is also a natural wonder of the world where up to 3,000 starlings fly in a giant whirling mass in near-perfect unison. Starlings are often singled out and hunted by predators like falcons, so this aerial formation is thought to be a natural defensive instinct.
How do they do it, though?
Scientists and naturalists have long wondered about this. Italian researchers and physicists from the Università Sapienza in Rome took a closer look at footage of starling murmurations and developed a mathematical model for what’s going on in these aerial feats.
What they found was only a small difference in speed between each adjacent bird, and that each starling is in fact simply copying the bird next to it, but with incredible speed.
“There is no leader in a flock; everyone imitates its neighbors,” said Dr. Antonio Culla of Università Sapienza in Rome. “And each bird is able to change its velocity a little bit in a very easy way.”
The team of physicists used video footage of starling flocks ranging from 10 birds to 3,000 to develop their mathematical model. To test the model, they used it in computer simulations of an artificial murmuration.
Birds influencing technology
The team believes that their study, published in Nature Communications, could influence engineers and tech developers in developing swarms of drones that could say, fly collectively over fields to tend crops. The mathematical model could also be useful in developing new methods for tracking space debris.
Source Study: Nature Communications — Marginal speed confinement resolves the conflict between correlation and control in collective behaviour | Nature Communications
