Study: Ants Outperform Humans in Cooperation Test, Weizmann Scientists Find

Ants and humans, both highly social species, share a unique trait: consistently cooperating to transport loads far exceeding their individual size. This shared behavior formed the basis of a fascinating evolutionary competition conducted by Prof. Ofer Feinerman and his team at the Weizmann Institute of Science. They asked: who is better at maneuvering a large load through a maze? The surprising results, published in the Proceedings of the National Academy of Sciences (PNAS), offer new insights into group decision-making and the advantages and disadvantages of cooperation versus individual action.

To compare these vastly different species, Tabea Dreyer and the research team created a real-world version of the “piano movers puzzle,” a classic computational problem from motion planning and robotics concerning how to move an oddly shaped object—like a piano—from one point to another in a complex environment. Instead of a piano, participants (both human and ant) were tasked with maneuvering a large T-shaped object across a rectangular space divided into three chambers connected by two narrow slits.

The researchers created two sets of mazes that differed only in size, to match the dimensions of ants and humans, as well as groups of different size. Recruiting study participants was easier in the case of humans, who volunteered simply because they were asked to participate, and probably because they liked the idea of a competition. Ants, on the other hand, are far from competitive. They joined because they were misled into thinking that the heavy load was a juicy edible morsel that they were transporting into their nest.

Unsurprisingly, humans, with their advanced cognitive abilities, excelled in the individual challenge, employing calculated strategies to easily outperform individual ants. However, the group challenge revealed a different story, particularly with larger groups. Not only did ant groups outperform individual ants, but they sometimes even surpassed human performance. These ant groups demonstrated calculated, strategic collective behavior, exhibiting a form of collective memory that helped them maintain direction and avoid repeating errors. In contrast, human group performance did not significantly improve and even declined when communication was restricted to mimic ant communication. In these constrained conditions, humans tended to choose “greedy” short-term solutions that proved detrimental in the long run, essentially opting for the lowest common denominator, according to the researchers.

“An ant colony is actually a family,” Feinerman says. “All the ants in the nest are sisters, and they have common interests. It’s a tightly knit society in which cooperation greatly outweighs competition. That’s why an ant colony is sometimes referred to as a super-organism, sort of a living body composed of multiple ‘cells’ that cooperate with one another. Our findings validate this vision. We’ve shown that ants acting as a group are smarter, that for them the whole is greater than the sum of its parts. In contrast, forming groups did not expand the cognitive abilities of humans. The famous ‘wisdom of the crowd’ that’s become so popular in the age of social networks didn’t come to the fore in our experiments.”