Human interaction heavily depends on inadvertent cues: A competitor's sweaty handshake before a negotiation, a girl blushing when introducing herself, or the trace of a smile crossing the face of a poker player all convey important information. Sara Mitri and colleagues at the Laboratory of Intelligent Systems (disclaimer: my former lab) at the EPFL in Switzerland have now shown that it is not just humans who can develop, detect and use inadvertent cues to their advantage (PNAS: "Evolution of Information Suppression in Communicating Robots with Conflicting Interests").
The researchers set up a group of S-bots equipped with omnidirectional cameras and light-emitting rings around their body in a bio-inspired foraging task (see picture above). Like many animals, the robots used visual cues to forage for two food sources in the arena. Rather than pre-programming the robots' control rules, the researchers used artificial evolution to develop the robots' control systems. As expected, robots capable of efficiently navigating the arena and locating food sources evolved in a matter of a few 100 generations.
This is when things became interesting: Due to the limited amount of food, robots now began to compete for resources. Robots began to evolve strategies to use light inadvertently emitted by their peers to rapidly pinpoint food locations, in some cases even physically pushing them away to make room for themselves. As evolution progressed, the exploited robots were soon all but extinct. A new generation of robots ensued that could conceal their presence by emitting confusing patterns of light or by ceasing to emit light altogether.
I think this research highlights an interesting point: Robots have applicability far beyond engineering. As a leading evolutionary biologist involved in the study put it: "Robots can be quite useful to get a better understanding of the interaction between organisms". While still in its infancy, watch out for robots boosting research in biology, psychology or medicine.