What is the term for the natural replacement of one community of living organisms by another?

The term that describes the natural replacement of one community of living organisms by another is "succession." Succession refers to the process through which ecosystems change and develop over time, often as the result of disturbances such as fires, floods, or human activities. This process can be seen in two primary forms: primary succession, which occurs on surfaces that have never been colonized before (like bare rock after a volcanic eruption), and secondary succession, which happens in areas where a disturbance has cleared an existing community but leaves the soil intact (like after a forest fire).

Adaptation refers to the process by which organisms adjust to their environments to improve their chances of survival and reproduction, which is distinct from the idea of community replacement.

Revolution generally refers to a significant change, often in a political or social context, and is not related to ecological processes.

Diffusion is a term used to describe the movement of particles from an area of higher concentration to an area of lower concentration and does not pertain to the ecological succession of communities.