Scientists have found one more important difference between human and other primates, which possibly played a considerable part in human evolution.

The man is the only primates, with white of the eye. The other monkeys have totally black eyes. This makes it possible only for human to determine the other people's intentions and emotions with the help of the eyes. While looking at monkey’s eyes it is quite impossible to understand not only its feelings, but even the direction of the eye sight.

Thus, the people at the very beginning of their development got an important means of communication that did not have other animals. Only human beings could know the thoughts of another representative of their kind. As they say, never trust the man who does not look in your eyes.