Ants have more ‘group smarts’ than humans, Israeli study finds
Weizmann Institute researchers say that when together, the insects outperform people in maneuvering a load through a maze
Reporter at The Times of Israel
A Weizmann Institute of Science team has found that ants have better group smarts than people when maneuvering a large load through a maze.
Prof. Ofer Feinerman, who led the research team, said the study showed humans’ cognitive abilities gave them an edge over ants when working individually. However, when ants joined forces and formed groups, they defeated groups of people working together.
The study recently appeared in the peer-reviewed journal Proceedings of the National Academy of Sciences.
Tabea Dreyer, one of the researchers, created a real-life version of what is known as the “piano movers puzzle,” a robotics problem that examines possible ways of moving an unusually shaped object – a piano, for example – from point A to point B in a complex environment.
Instead of a piano, the ants and people were given a large T-shaped object that they had to maneuver across a rectangular space that was divided into three chambers and connected by two narrow slits.
The researchers created two sets of mazes, one that was ant-sized and one that was human-sized.
Recruiting people to participate in the study was easy, the researchers said. People volunteered because they “probably liked the idea of a competition.”
Ants, however, are not competitive. The researchers said the ants participated in the study “because they were led into thinking that the heavy load they were transporting into their nest was a juicy edible morsel.”
The humans, scientifically known as Homo sapiens, competed against black ants, scientifically known as Paratrechina longicornis. The names derives from their long antennae, though they are sometimes referred to as “crazy ants” for their tendency to dash around.
This species of black ant, about three millimeters long, is common around the world. In Israel, they are particularly prevalent along the coast and in the south of the country.
The ants tackled the maze challenge in three combinations: independently, in a small group of about seven, and then in a large group of about 80.
Humans handled the task in three parallel combinations: as individuals, in a small group of six to nine people, and in a large group of 26.
To make the comparison as meaningful as possible, some (though not all) of the human groups were instructed to avoid communicating through speaking or gestures, even wearing surgical masks and sunglasses to conceal their mouths and eyes.
Ants communicate through pheromones, chemical signals between members of the same species. However, the puzzle was designed so that they could not use this form of communication.
In addition, human participants were told to hold onto the load they had to maneuver by the handles alone, in a way that simulated the ants’ behavior. The handles measured the pulling force applied by each person throughout the attempt.
The researchers repeated the experiment numerous times for each combination. They then analyzed the videos and the data while using computer simulations and various physics models.
The researchers found that people worked better alone than in groups. For the ants, it was the reverse.
Groups of ants cooperated in a “calculated and strategic manner,” the researchers said, “exhibiting collective memory that helped them persist in a particular direction of motion to avoid repeating mistakes.”
Humans failed to significantly improve their performance when acting in groups. Moreover, when communication between group members was restricted to resemble that of ants, their performance dropped even further. They tended to opt for short-term solutions that were not beneficial to the project in the long term.
“An ant colony is actually a family,” Feinerman said. “They have a common interest.” They form a “tightly knit society in which cooperation greatly outweighs competition.”
He said that an ant colony is sometimes referred to as a super-organism, a living body composed of multiple “cells.”
In contrast, when people worked in groups, they were unable to improve their abilities to plan strategically.
The researchers joked that “despite all the challenges of human cooperation,” several scientists “successfully joined forces in this study,” including Dr. Ehud Fonio, Prof. Nir Gov, and then-PhD student Dr. Amir Haluts, and Prof. Amos Korman of the University of Haifa.
