Define ecological succession and stress that it may take centuries to accomplish.
Introduce primary succession, from bare rock to mid succession plants. Examine how algae dissolve rock to obtain minerals and then convert the rock to soil when they decompose. Discuss how the thin layer of poor soil becomes hospitable for plant life. Indicate how new species colonize the area and outcompete the mid succession plants by adapting to temp. and rainfall.
Introduce and discuss secondary succession, which starts from soil and not rock. Explain how trees replace grasses and wildflowers and become the pioneer species. Lead from pioneer species to climax community due to rain and temperature and shade provided,