Is it important that computers and robots tell us the truth? Or should they learn to lie - like their human makers?

In an experiment performed in a Swiss laboratory, 10 robots with downward-facing sensors competed for "food" - a light-colored ring on the floor. At the other end of the space, a darker ring - "poison" - was placed. The robots earned points for how much time they spent near food as opposed to poison.

The experimenters, engineers Sara Mitri and Dario Floreano and evolutionary biologist Laurent Keller, also gave the robots the ability to talk with each other. Each robot can produce a blue light that can be seen by the others and which can give away the position of the "food" ring. Over time, the robots evolved to deceive each other about the food ring.