What is one important characteristic of all human systems?

Language is often seen to be the single characteristic present in all human life Its ranges from symbolic such as cave paintings and star constellations, and text. 

Human system was once considered to be all spiritual, as people never knew about the logic that is present between the different body parts. There is a sense of strong coordination between the different organs inside the human body, as each of the human body organ is more or less dependent upon the working of the other.As, there is complex set of interrelated organs which combines to form a more complex multi-cellular body. So, the different organs are formed from a single and then after many steps of development the different organs and systems come into being,while each of the system works in coordination with the rest of the body's system.