Nature

From the depts of the underwater caves to the heights of the snowy capped summits spans the natural habitat, the source of life and the life itself. By the inhabitants of the world, it is furtherly divided into three sections:   Where? The big structures, considered relatively unchanging in a human lifetime, e.g., mountains, valleys, rivers, woods.   Who? The many lifeforms feeding and shaping the world, e.g., plants, animals, people.   How? The laws by which the changes in/to the world occur, e.g., laws of physics, illnesses, laws governing mental/emotional states.