Our hominin ancestors have lived in social groups for a very long time, and this has led us to be exquisitely sensitive to subtle interpersonal cues. These cues include facial expression, tone of voice, direction of gaze, and other forms of body language. They contribute to our crucial ability to infer what another person knows or might be thinking, as well as his or her emotional state.

Our hominin ancestors have lived in social groups for a very long time, and this has led us to be exquisitely sensitive to subtle interpersonal cues. These cues include facial expression, tone of voice, direction of gaze, and other forms of body language. They contribute to our crucial ability to infer what another person knows or might be thinking, as well as his or her emotional state.