Why Ants Handle Traffic Better Than You

This article was originally published on NPR.org – You can read or listen to the original story here.

Could studying ants reveal clues to reducing highway traffic jams? Physicist Apoorva Nagar at the Indian Institute of Space Science and Technology thinks the answer is yes.

Nagar says he got interested in the topic when he came across a study by German and Indian researchers showing that ants running along a path were able to maintain a steady speed even when there were a large number of ants on the path.

Nagar says there are three main reasons ants don’t jam up. No. 1, ants don’t have egos. They don’t show off by zooming past people.

“The second thing is, they do not mind a few accidents or collisions,” say Nagar. So unless there’s a serious pileup, they just keep going.

Road rage? Probably not.

The third reason, he says, is that ants seem to get more disciplined when paths get crowded, running in straighter lines and varying their speed less. They’re less likely to make unexpected moves in this sort of heavy traffic. It’s the kind of steady control you see when a computer, rather than a human, is controlling a car. There’s less variability unless it’s absolutely called for.

Nagar felt this kind of behavior could be explained by something called the Langevin equation, an equation physicists use when describing the movement of liquids, or how individual atoms behave in a lattice.

And what, you ask, is the Langevin equation? I wasn’t entirely sure, so I turned to Thomas D. Donnelly, a physics professor at Harvey Mudd College. “This is basically a reworking of Newton’s famous F=MA equation,” Donnelly told me — force equals mass times acceleration.

“So it’s all Newton,” Donnelly says, “but they’re using a special description of the forces which includes a random component.”