We individual humans, as well as all of human civilization, are totally interdependent with the global ecological system – dependent upon clean air, pure water, a stable climate, healthy forests, healthy grasslands, healthy ocean ecosystems, and fertile soil with its teaming microscopic life. Individual humans and human civilizations are subject to the laws of physics, the rules of chemistry and ecological principles – there are no exceptions! In what ways do we humans depend upon the ecosystems of Earth? In what ways does human society affect the ecosystems of Earth? What can we learn from nature’s laws about how to live on Earth sustainably? What is a healthy human ecology? What is the future of human civilization and its relationship to the ecosphere?