The meerkats call to one another as they travel. One of their sounds is a gentle mew that researchers have called a “move call.” It seems to mean, “I’m about ready to move on from this dirt patch. Who’s with me?”

In a 2010 study, Dr. Manser and her colleagues studied move calls in a dozen meerkat groups living in the Kalahari Desert in South Africa. Groups ranged from six to 19 individuals. But the scientists found that only about three group members had to mew before the whole party decided to move along. The group didn’t change direction, but it would double its speed to reach better foraging grounds.

Biologists call this phenomenon — when animals change their behavior in response to a critical mass of their peers doing something — a quorum response. Dr. Manser thinks quorum responses show up in human decision making, too.

“If you’re in a group and somebody says, ‘Let’s go for a pizza,’ and nobody joins in, nothing’s going to happen,” she said. But if the pizza craver is joined by a couple of friends, their argument becomes much more convincing.

In another set of experiments, Dr. Manser and a co-author found that it didn’t matter whether meerkats making move calls were dominant or subordinate within the group. Rather, she said, “It depends on how determined an individual appears.”