Class Notes 3 Succession

I. Succession A. As resources are used up, or become available, different species of plants or animals become present. B. Scientists call these changes in species over time succession.

II. Primary Succession A.Occurs on an area of bare rock or sand where nothing has ever lived. B.First, pioneer species, such as lichen, move in.

II. Primary Succession cont C. The lichen decomposes, improving the soil. D. Eventually larger plants, then larger animals can move in.

III. Secondary Succession A.When a community is disrupted because of a natural disaster or human change. B.Because soil already exists, secondary succession may take less time than primary succession to reach a climax community.

IV. Climax Community The community will mature until limiting factors have stopped it. At this point, it has reached its climax community. Secondary successionClimax community

Summary What is succession? What are the two types? Compare and contrast. Why do communities reach a climax?