Greater mouse-tailed bats live in crowded colonies in caves and also forage in groups, even though the noise from nearby bats can be distracting in using sonar to hunt prey.

Why do they do this? And how do they adjust the distances from one another as they fly? Noam Cvikel and Yossi Yovel of Tel Aviv University set out to answer these questions.

The answer, Dr. Yovel said, is the “bag of chips” effect. It’s probably the crunching sound that attracts the guy in the next cubicle, but for bats, it’s the sonar signal.

When one bat hears another bat hunting, it flies toward the sound, because it signals the presence of food. Of course, if the group gets too crowded, the bats have to spread out because all the echolocation noise makes it hard to hunt.