How the brains of social animals synchronise and expand one another
Sofia Quaglia writes: Humans are not the only creatures that show a refined grasp of social norms. If a group of adult male rhesus monkeys (Macaca mulatta) find themselves sitting around a turning table set with food, they will display an ‘I scratch your back, you scratch mine’ ethos of reciprocity. One monkey will offer another one a piece of fruit and, what’s more, will expect the gesture to be reciprocated. If the offer isn’t forthcoming, the first monkey is…