Level of Organization

Scientific knowledge is organized hierarchically in levels of organization, where each level describes nature on a certain scope or resolution, from microscopic to macroscopic levels. Although at any given level of organization the behavior emerges from the behavior of the subsystems at the immediately lower level of organization, it can be described in an independent way.

Scientific knowledge is organised in levels, not because reduction in principle is impossible, but because nature is organised in levels, and the pattern at each level is most clearly discerned by abstracting from the detail of the levels far below. [. . .] And nature is organised in levels because hierarchic structures – systems of Chinese boxes – provide the most viable form for any system of even moderate complexity. — Herbert A. Simon ('The Organisation of Complex Systems’ in "Hierarchy Theory: The Challenge of Complex Systems", 1973, p. 26)

In ecology, the levels of organizations are the five known levels of environmental classification:

• Biosphere
• Ecosystem
• Community
• Population
• Organism

In anatomy, organic life-forms and organisms, the levels are

• Organism
• Organ System
• Organ
• Tissue
• Cell

In physics, the levels of organizations for matter in general are:

• Molecule (biomolecule, cells)
• Atom
• Elementary particle