Individual ants are strong but lack a strong sense of direction, according to a new study of longhorn crazy ants or Paratrechina longicornis, by Ofer Feinerman, a researcher at the Weizmann Institute of Science.
So, in order to get objects moved and to the right place, the group relies on a leader or scout ant to emerge and help steer the group and direct the operation.
“The individuals come with the solution. The group gives it the muscle power. The group is tuned to be maximally sensitive to the leader ants,” Feinerman explained. “As far as we can tell the scout is no different than the other ants. No one designates the leader, she—not he—designates herself because she has current knowledge about the correct direction.”
Once the leader ant takes charge and sets the group on course, the other ants provide their muscle to help get the collective job done.
“The individual ant has the idea of how to pass an obstacle but lacks the muscle power to move the load,” Feinerman added. “The group is there to amplify the leader’s strength so that she can actually implement her idea.”
The leader’s job is shortlived and leaders change as often as every few seconds to help move the group along. The result is the zigzag pattern often seen among ants as the group steers off course and a new leader emerges to push the group back on track.
The study, which was just published in the journal Nature Communications, also offers insight on how ant group dynamics encourage members to conform.
“If you move something huge, you need many, many more ants,” the Israeli researcher said about his ant observations. “And then the force that each ant feels through the object is much stronger. So… all the ants feel a stronger urge to act as conformists” to help carry the load.”