1. Succession
Primary and secondary

2. Succession is the series of orderly, natural changes that take place in the communities of an ecosystem.

3. Primary succession is the colonization on new sites by organisms
Primary succession is the colonization on new sites by organisms. It starts with bare rock.

5. Bare rock is broken down into smaller pieces by weathering.

9. The first organisms to move into a new area are called Pioneer Organisms.
Lichens are an example of a pioneer organism.

12. Pioneer organisms break down the rock
Pioneer organisms break down the rock. When they die and decompose, their remains, along with tiny pieces of rock form soil making it possible for mosses and ferns to grow.

23. Over time the community keeps changing until it reaches a point where succession almost ceases. The community is now called a Climax Community.