The MRN complex

What about gaze as a communicative signal? In contrast to other primates, humans have evolved a large white sclera and marked eyebrows, making the eye region highly conspicuous and ideally suited for gaze following, and it has been argued that this is an evolutionary byproduct of the cooperative nature of humans. Not only can humans follow gaze, but they can also use gaze to actively direct each other’s attention, or, by eye squinting and lowering eyebrows, to make it more difficult for others to follow gaze (something that is perceived as unfriendly and uncooperative). Non-human primates are clearly sensitive to the directed gaze of others, and therefore they already possess a fundamental prerequisite for using gaze as a communicative signal. Whether or not they are also able to influence the attention of receivers by manipulating gaze cues is currently being investigated.