We are part of the natural world. Our minds and emotions evolved in nature. To understand them we have to understand that evolution. We know a lot about the origin of the body. In other words, how the human form came about and the rate at which the forebrain grew and the head shaped. But the one thing that_s been lacking in the explanation of the origin of humanity and, therefore, lacking in terms of the meaning of humanity is the origin of our social behavior.